1
|
Shirokawa Y, Shimada M, Shimada N, Sawai S. Prestalk-like positioning of de-differentiated cells in the social amoeba Dictyostelium discoideum. Sci Rep 2024; 14:7677. [PMID: 38561423 PMCID: PMC10985001 DOI: 10.1038/s41598-024-58277-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 03/27/2024] [Indexed: 04/04/2024] Open
Abstract
The social amoeba Dictyostelium discoideum switches between solitary growth and social fruitification depending on nutrient availability. Under starvation, cells aggregate and form fruiting bodies consisting of spores and altruistic stalk cells. Once cells socially committed, they complete fruitification, even if a new source of nutrients becomes available. This social commitment is puzzling because it hinders individual cells from resuming solitary growth quickly. One idea posits that traits that facilitate premature de-commitment are hindered from being selected. We studied outcomes of the premature de-commitment through forced refeeding. Our results show that when refed cells interacted with non-refed cells, some of them became solitary, whereas a fraction was redirected to the altruistic stalk, regardless of their original fate. The refed cells exhibited reduced cohesiveness and were sorted out during morphogenesis. Our findings provide an insight into a division of labor of the social amoeba, in which less cohesive individuals become altruists.
Collapse
Affiliation(s)
- Yuka Shirokawa
- Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan.
| | - Masakazu Shimada
- Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan
| | - Nao Shimada
- Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan
| | - Satoshi Sawai
- Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan
- Research Center for Complex Systems Biology, Universal Biology Institute, University of Tokyo, Tokyo, 153-8902, Japan
| |
Collapse
|
2
|
Leeks A, Bono LM, Ampolini EA, Souza LS, Höfler T, Mattson CL, Dye AE, Díaz-Muñoz SL. Open questions in the social lives of viruses. J Evol Biol 2023; 36:1551-1567. [PMID: 37975507 DOI: 10.1111/jeb.14203] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 06/12/2023] [Accepted: 06/21/2023] [Indexed: 11/19/2023]
Abstract
Social interactions among viruses occur whenever multiple viral genomes infect the same cells, hosts, or populations of hosts. Viral social interactions range from cooperation to conflict, occur throughout the viral world, and affect every stage of the viral lifecycle. The ubiquity of these social interactions means that they can determine the population dynamics, evolutionary trajectory, and clinical progression of viral infections. At the same time, social interactions in viruses raise new questions for evolutionary theory, providing opportunities to test and extend existing frameworks within social evolution. Many opportunities exist at this interface: Insights into the evolution of viral social interactions have immediate implications for our understanding of the fundamental biology and clinical manifestation of viral diseases. However, these opportunities are currently limited because evolutionary biologists only rarely study social evolution in viruses. Here, we bridge this gap by (1) summarizing the ways in which viruses can interact socially, including consequences for social evolution and evolvability; (2) outlining some open questions raised by viruses that could challenge concepts within social evolution theory; and (3) providing some illustrative examples, data sources, and conceptual questions, for studying the natural history of social viruses.
Collapse
Affiliation(s)
- Asher Leeks
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, USA
- Quantitative Biology Institute, Yale University, New Haven, Connecticut, USA
| | - Lisa M Bono
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Elizabeth A Ampolini
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Lucas S Souza
- Department of Ecology & Evolutionary Biology, University of Tennessee, Knoxville, Tennessee, USA
| | - Thomas Höfler
- Institute of Virology, Freie Universität Berlin, Berlin, Germany
| | - Courtney L Mattson
- Department of Microbiology and Molecular Genetics, University of California Davis, Davis, California, USA
| | - Anna E Dye
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, North Carolina, USA
| | - Samuel L Díaz-Muñoz
- Department of Microbiology and Molecular Genetics, University of California Davis, Davis, California, USA
- Genome Center, University of California Davis, Davis, California, USA
| |
Collapse
|
3
|
Goodman JR, Caines A, Foley RA. Shibboleth: An agent-based model of signalling mimicry. PLoS One 2023; 18:e0289333. [PMID: 37523380 PMCID: PMC10389733 DOI: 10.1371/journal.pone.0289333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 07/17/2023] [Indexed: 08/02/2023] Open
Abstract
Mimicry is an essential strategy for exploiting competitors in competitive co-evolutionary relationships. Protection against mimicry may, furthermore, be a driving force in human linguistic diversity: the potential harm caused by failing to detect mimicked group-identity signals may select for high sensitivity to mimicry of honest group members. Here we describe the results of five agent-based models that simulate multi-generational interactions between two groups of individuals: original members of a group with an honest identity signal, and members of an outsider group who mimic that signal, aiming to pass as members of the in-group. The models correspond to the Biblical story of Shibboleth, where a tribe in conflict with another determines tribe affiliation by asking individuals to pronounce the word, 'Shibboleth.' In the story, failure to reproduce the word phonetically resulted in death. Here, we run five different versions of a 'Shibboleth' model: a first, simple version, which evaluates whether a composite variable of mimicry quality and detection quality is a superior predictor to the model's outcome than is cost of detection. The models thereafter evaluate variations on the simple model, incorporating group-level behaviours such as altruistic punishment. Our results suggest that group members' sensitivity to mimicry of the Shibboleth-signal is a better predictor of whether any signal of group identity goes into fixation in the overall population than is the cost of mimicry detection. Thus, the likelihood of being detected as a mimic may be more important than the costs imposed on mimics who are detected. This suggests that theoretical models in biology should place greater emphasis on the likelihood of detection, which does not explicitly entail costs, rather than on the costs to individuals who are detected. From a language learning perspective, the results suggest that admission to group membership through linguistic signals is powered by the ability to imitate and evade detection as an outsider by existing group members.
Collapse
Affiliation(s)
- Jonathan R Goodman
- Leverhulme Centre for Human Evolutionary Studies, University of Cambridge, Cambridge, United Kingdom
- Darwin College, University of Cambridge, Cambridge, United Kingdom
| | - Andrew Caines
- ALTA Institute, University of Cambridge, Cambridge, United Kingdom
| | - Robert A Foley
- Leverhulme Centre for Human Evolutionary Studies, University of Cambridge, Cambridge, United Kingdom
| |
Collapse
|
4
|
Leeks A, Young PG, Turner PE, Wild G, West SA. Cheating leads to the evolution of multipartite viruses. PLoS Biol 2023; 21:e3002092. [PMID: 37093882 PMCID: PMC10159356 DOI: 10.1371/journal.pbio.3002092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 05/04/2023] [Accepted: 03/22/2023] [Indexed: 04/25/2023] Open
Abstract
In multipartite viruses, the genome is split into multiple segments, each of which is transmitted via a separate capsid. The existence of multipartite viruses poses a problem, because replication is only possible when all segments are present within the same host. Given this clear cost, why is multipartitism so common in viruses? Most previous hypotheses try to explain how multipartitism could provide an advantage. In so doing, they require scenarios that are unrealistic and that cannot explain viruses with more than 2 multipartite segments. We show theoretically that selection for cheats, which avoid producing a shared gene product, but still benefit from gene products produced by other genomes, can drive the evolution of both multipartite and segmented viruses. We find that multipartitism can evolve via cheating under realistic conditions and does not require unreasonably high coinfection rates or any group-level benefit. Furthermore, the cheating hypothesis is consistent with empirical patterns of cheating and multipartitism across viruses. More broadly, our results show how evolutionary conflict can drive new patterns of genome organisation in viruses and elsewhere.
Collapse
Affiliation(s)
- Asher Leeks
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Department of Biology, University of Oxford, Oxford, United Kingdom
| | | | - Paul Eugene Turner
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, United States of America
- Quantitative Biology Institute, Yale University, New Haven, Connecticut, United States of America
| | - Geoff Wild
- Department of Mathematics, The University of Western Ontario, London, Canada
| | | |
Collapse
|
5
|
Rautiala P, Gardner A. The geometry of evolutionary conflict. Proc Biol Sci 2023; 290:20222423. [PMID: 36750194 PMCID: PMC9904945 DOI: 10.1098/rspb.2022.2423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Conflicts of interest abound not only in human affairs but also in the biological realm. Evolutionary conflict occurs over multiple scales of biological organization, from genetic outlawry within genomes, to sibling rivalry within nuclear families, to collective-action disputes within societies. However, achieving a general understanding of the dynamics and consequences of evolutionary conflict remains an outstanding challenge. Here, we show that a development of R. A. Fisher's classic 'geometric model' of adaptation yields novel and surprising insights into the dynamics of evolutionary conflict and resulting maladaptation, including the discoveries that: (i) conflict can drive evolving traits arbitrarily far away from all parties' optima and, indeed, if all mutations are equally likely then contested traits are more often than not driven outwith the zone of actual conflict (hyper-maladaptation); (ii) evolutionary conflicts drive persistent maladaptation of orthogonal, non-contested traits (para-maladaptation); and (iii) modular design greatly ameliorates conflict-driven maladaptation, thereby facilitating major transitions in individuality.
Collapse
Affiliation(s)
- Petri Rautiala
- School of Biology, University of St Andrews, Greenside Place, St Andrews KY16 9TH, UK
| | - Andy Gardner
- School of Biology, University of St Andrews, Greenside Place, St Andrews KY16 9TH, UK
| |
Collapse
|
6
|
Liu M, West SA, Wild G. The evolution of manipulative cheating. eLife 2022; 11:e80611. [PMID: 36193888 PMCID: PMC9633066 DOI: 10.7554/elife.80611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 10/03/2022] [Indexed: 01/07/2023] Open
Abstract
A social cheat is typically assumed to be an individual that does not perform a cooperative behaviour, or performs less of it, but can still exploit the cooperative behaviour of others. However, empirical data suggests that cheating can be more subtle, involving evolutionary arms races over the ability to both exploit and resist exploitation. These complications have not been captured by evolutionary theory, which lags behind empirical studies in this area. We bridge this gap with a mixture of game-theoretical models and individual-based simulations, examining what conditions favour more elaborate patterns of cheating. We found that as well as adjusting their own behaviour, individuals can be selected to manipulate the behaviour of others, which we term 'manipulative cheating'. Further, we found that manipulative cheating can lead to dynamic oscillations (arms races), between selfishness, manipulation, and suppression of manipulation. Our results can help explain both variation in the level of cheating, and genetic variation in the extent to which individuals can be exploited by cheats.
Collapse
Affiliation(s)
- Ming Liu
- Department of Biology, University of OxfordOxfordUnited Kingdom
| | | | - Geoff Wild
- Department of Mathematics, The University of Western OntarioLondonCanada
| |
Collapse
|
7
|
Developmental constraints enforce altruism and avert the tragedy of the commons in a social microbe. Proc Natl Acad Sci U S A 2022; 119:e2111233119. [PMID: 35858311 PMCID: PMC9303850 DOI: 10.1073/pnas.2111233119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Organisms often generate benefits shared among their whole group, but such cooperation is vulnerable to collapse if individuals can instead benefit by exploiting the cooperation of others. While relatedness can promote cooperation, many species lack reliable mechanisms to ensure high relatedness. They are therefore vulnerable to a breakdown of cooperation unless they are able to enforce cooperation. We test this idea through experimental manipulation of group composition in a social microbe. We find that groups avert the expected collapse in cooperation at low relatedness due to inadvertent enforcement of cooperation by a mechanism that prevents errors in multicellular development. Our findings explain how mechanisms that promote cooperation can arise as by-products of natural selection acting on traits in other contexts. Organisms often cooperate through the production of freely available public goods. This can greatly benefit the group but is vulnerable to the “tragedy of the commons” if individuals lack the motivation to make the necessary investment into public goods production. Relatedness to groupmates can motivate individual investment because group success ultimately benefits their genes’ own self-interests. However, systems often lack mechanisms that can reliably ensure that relatedness is high enough to promote cooperation. Consequently, groups face a persistent threat from the tragedy unless they have a mechanism to enforce investment when relatedness fails to provide adequate motivation. To understand the real threat posed by the tragedy and whether groups can avert its impact, we determine how the social amoeba Dictyostelium discoideum responds as relatedness decreases to levels that should induce the tragedy. We find that, while investment in public goods declines as overall within-group relatedness declines, groups avert the expected catastrophic collapse of the commons by continuing to invest, even when relatedness should be too low to incentivize any contribution. We show that this is due to a developmental buffering system that generates enforcement because insufficient cooperation perturbs the balance of a negative feedback system controlling multicellular development. This developmental constraint enforces investment under the conditions expected to be most tragic, allowing groups to avert a collapse in cooperation. These results help explain how mechanisms that suppress selfishness and enforce cooperation can arise inadvertently as a by-product of constraints imposed by selection on different traits.
Collapse
|
8
|
Sharp C, Foster KR. Host control and the evolution of cooperation in host microbiomes. Nat Commun 2022; 13:3567. [PMID: 35732630 PMCID: PMC9218092 DOI: 10.1038/s41467-022-30971-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 05/27/2022] [Indexed: 12/14/2022] Open
Abstract
Humans, and many other species, are host to diverse symbionts. It is often suggested that the mutual benefits of host-microbe relationships can alone explain cooperative evolution. Here, we evaluate this hypothesis with evolutionary modelling. Our model predicts that mutual benefits are insufficient to drive cooperation in systems like the human microbiome, because of competition between symbionts. However, cooperation can emerge if hosts can exert control over symbionts, so long as there are constraints that limit symbiont counter evolution. We test our model with genomic data of two bacterial traits monitored by animal immune systems. In both cases, bacteria have evolved as predicted under host control, tending to lose flagella and maintain butyrate production when host-associated. Moreover, an analysis of bacteria that retain flagella supports the evolution of host control, via toll-like receptor 5, which limits symbiont counter evolution. Our work puts host control mechanisms, including the immune system, at the centre of microbiome evolution.
Collapse
Affiliation(s)
- Connor Sharp
- Department of Zoology, University of Oxford, Oxford, UK.
- Department of Biochemistry, University of Oxford, Oxford, UK.
| | - Kevin R Foster
- Department of Zoology, University of Oxford, Oxford, UK.
- Department of Biochemistry, University of Oxford, Oxford, UK.
| |
Collapse
|
9
|
De Dreu CKW, Triki Z. Intergroup conflict: origins, dynamics and consequences across taxa. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210134. [PMID: 35369751 PMCID: PMC8977662 DOI: 10.1098/rstb.2021.0134] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Although uniquely destructive and wasteful, intergroup conflict and warfare are not confined to humans. They are seen across a range of group-living species, from social insects, fishes and birds to mammals, including nonhuman primates. With its unique collection of theory, research and review contributions from biology, anthropology and economics, this theme issue provides novel insights into intergroup conflict across taxa. Here, we introduce and organize this theme issue on the origins and consequences of intergroup conflict. We provide a coherent framework by modelling intergroup conflicts as multi-level games of strategy in which individuals within groups cooperate to compete with (individuals in) other groups for scarce resources, such as territory, food, mating opportunities, power and influence. Within this framework, we identify cross-species mechanisms and consequences of (participating in) intergroup conflict. We conclude by highlighting crosscutting innovations in the study of intergroup conflict set forth by individual contributions. These include, among others, insights on how within-group heterogeneities and leadership relate to group conflict, how intergroup conflict shapes social organization and how climate change and environmental degradation transition intergroup relations from peaceful coexistence to violent conflict. This article is part of the theme issue ‘Intergroup conflict across taxa’.
Collapse
Affiliation(s)
- Carsten K W De Dreu
- Institute of Psychology, Leiden University, Leiden, The Netherlands.,Center for Research in Experimental Economics and Political Decision Making, University of Amsterdam, Amsterdam, The Netherlands
| | - Zegni Triki
- Department of Zoology, Stockholm University, Stockholm, Sweden
| |
Collapse
|
10
|
Oliveira RC, Di Pietro V, Quezada-Euán JJG, Pech JR, Moo-Valle H, Wenseleers T. Tragedy of the commons in Melipona bees revisited. Biol Lett 2022; 18:20210498. [PMID: 35078331 PMCID: PMC8790378 DOI: 10.1098/rsbl.2021.0498] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 12/06/2021] [Indexed: 01/28/2023] Open
Abstract
Melipona stingless bees display a paradoxical overproduction of queens, which are later eliminated by nest-mate workers. Mechanistically, it was suggested that the monoterpenoid geraniol deposited into newly provisioned cells by adult bees would cause larvae to develop into queens in Melipona beecheii. This system could be evolutionarily stable if many of these new queens were to leave the nest and parasitize other genetically unrelated colonies nearby, as was shown to occur in a congeneric species. Here, we use microsatellite markers to test whether queen overproduction could be a strategy by which adult workers control the caste fate of the developing larvae to export copies of their own genes to the rest of the population via queen parasitism in M. beecheii. In addition, we re-examined whether artificially increasing the levels of geraniol indeed caused larvae to develop as queens rather than workers. Contrary to our prediction, we found no evidence for queen parasitism in M. beecheii and observed no effect of geraniol on the rearing of new queens. Together, these results support the original 'tragedy of the commons' hypothesis for queen overproduction in Melipona bees, where individual larvae selfishly bias their development towards the queen pathway according to their best evolutionary interests.
Collapse
Affiliation(s)
- Ricardo Caliari Oliveira
- Laboratory of Socioecology and Social Evolution, Department of Biology, KU Leuven, 3000 Leuven, Belgium
| | - Viviana Di Pietro
- Laboratory of Socioecology and Social Evolution, Department of Biology, KU Leuven, 3000 Leuven, Belgium
| | - José Javier G. Quezada-Euán
- Departamento de Apicultura Tropical, CCBA Universidad Autónoma de Yucatán, km 15. Carr. Mérida-Xmatkuil, Cp. 97000 Mérida, Mexico
| | - Jorge Ramirez Pech
- Abejasmiel, Calle 41C #268 por 42 Y 46 Francisco de Montejo III, Mérida, Yucatán, Mexico
| | - Humberto Moo-Valle
- Departamento de Apicultura Tropical, CCBA Universidad Autónoma de Yucatán, km 15. Carr. Mérida-Xmatkuil, Cp. 97000 Mérida, Mexico
| | - Tom Wenseleers
- Laboratory of Socioecology and Social Evolution, Department of Biology, KU Leuven, 3000 Leuven, Belgium
| |
Collapse
|
11
|
Opachaloemphan C, Mancini G, Konstantinides N, Parikh A, Mlejnek J, Yan H, Reinberg D, Desplan C. Early behavioral and molecular events leading to caste switching in the ant Harpegnathos. Genes Dev 2021; 35:410-424. [PMID: 33602869 PMCID: PMC7919410 DOI: 10.1101/gad.343699.120] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 01/15/2021] [Indexed: 12/14/2022]
Abstract
Ant societies show a division of labor in which a queen is in charge of reproduction while nonreproductive workers maintain the colony. In Harpegnathos saltator, workers retain reproductive ability, inhibited by the queen pheromones. Following the queen loss, the colony undergoes social unrest with an antennal dueling tournament. Most workers quickly abandon the tournament while a few workers continue the dueling for months and become gamergates (pseudoqueens). However, the temporal dynamics of the social behavior and molecular mechanisms underlining the caste transition and social dominance remain unclear. By tracking behaviors, we show that the gamergate fate is accurately determined 3 d after initiation of the tournament. To identify genetic factors responsible for this commitment, we compared transcriptomes of different tissues between dueling and nondueling workers. We found that juvenile hormone is globally repressed, whereas ecdysone biosynthesis in the ovary is increased in gamergates. We show that molecular changes in the brain serve as earliest caste predictors compared with other tissues. Thus, behavioral and molecular data indicate that despite the prolonged social upheaval, the gamergate fate is rapidly established, suggesting a robust re-establishment of social structure.
Collapse
Affiliation(s)
- Comzit Opachaloemphan
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
| | - Giacomo Mancini
- Department of Biology, New York University, New York, New York 10003, USA
| | | | - Apurva Parikh
- Department of Biology, New York University, New York, New York 10003, USA
| | - Jakub Mlejnek
- Department of Biology, New York University, New York, New York 10003, USA
| | - Hua Yan
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
- Howard Hughes Medical Institute, New York University School of Medicine, New York, New York 10016, USA
| | - Danny Reinberg
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York 10016, USA
- Howard Hughes Medical Institute, New York University School of Medicine, New York, New York 10016, USA
| | - Claude Desplan
- Department of Biology, New York University, New York, New York 10003, USA
| |
Collapse
|
12
|
Boutry J, Dujon AM, Gerard AL, Tissot S, Macdonald N, Schultz A, Biro PA, Beckmann C, Hamede R, Hamilton DG, Giraudeau M, Ujvari B, Thomas F. Ecological and Evolutionary Consequences of Anticancer Adaptations. iScience 2020; 23:101716. [PMID: 33241195 PMCID: PMC7674277 DOI: 10.1016/j.isci.2020.101716] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Cellular cheating leading to cancers exists in all branches of multicellular life, favoring the evolution of adaptations to avoid or suppress malignant progression, and/or to alleviate its fitness consequences. Ecologists have until recently largely neglected the importance of cancer cells for animal ecology, presumably because they did not consider either the potential ecological or evolutionary consequences of anticancer adaptations. Here, we review the diverse ways in which the evolution of anticancer adaptations has significantly constrained several aspects of the evolutionary ecology of multicellular organisms at the cell, individual, population, species, and ecosystem levels and suggest some avenues for future research.
Collapse
Affiliation(s)
- Justine Boutry
- CREEC/CANECEV (CREES), MIVEGEC, Unité Mixte de Recherches, IRD 224–CNRS 5290–Université de Montpellier, Montpellier, France
| | - Antoine M. Dujon
- CREEC/CANECEV (CREES), MIVEGEC, Unité Mixte de Recherches, IRD 224–CNRS 5290–Université de Montpellier, Montpellier, France
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia France
| | - Anne-Lise Gerard
- CREEC/CANECEV (CREES), MIVEGEC, Unité Mixte de Recherches, IRD 224–CNRS 5290–Université de Montpellier, Montpellier, France
| | - Sophie Tissot
- CREEC/CANECEV (CREES), MIVEGEC, Unité Mixte de Recherches, IRD 224–CNRS 5290–Université de Montpellier, Montpellier, France
| | - Nick Macdonald
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia France
| | - Aaron Schultz
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia France
| | - Peter A. Biro
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia France
| | - Christa Beckmann
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia France
- School of Science, Western Sydney University, Parramatta, NSW, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Rodrigo Hamede
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia
| | - David G. Hamilton
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia
| | - Mathieu Giraudeau
- CREEC/CANECEV (CREES), MIVEGEC, Unité Mixte de Recherches, IRD 224–CNRS 5290–Université de Montpellier, Montpellier, France
| | - Beata Ujvari
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC, Australia France
- School of Natural Sciences, University of Tasmania, Hobart, TAS, Australia
| | - Frédéric Thomas
- CREEC/CANECEV (CREES), MIVEGEC, Unité Mixte de Recherches, IRD 224–CNRS 5290–Université de Montpellier, Montpellier, France
| |
Collapse
|
13
|
Abstract
Sperm competition was defined by Geoff Parker 50 years ago as the competition between sperm from two or more males over the fertilization of a set of eggs. Since the publication of his seminal paper, sperm competition has developed into a large field of research, and many aspects are still being discovered. One of the relatively poorly understood aspects is the importance of selection and competition among sperm within the ejaculate of a male. The sheer number of sperm present in a male's ejaculate suggests that the competition among sibling sperm produced by the same male may be intense. In this review, we summarize Parker's theoretical models generating predictions about the evolution of sperm traits under the control of the haploid gamete as opposed to the diploid male. We review the existing evidence of within-ejaculate competition from a wide range of fields and taxa. We also discuss the conceptual and practical hurdles we have been facing to study within-ejaculate sperm competition, and how novel technologies may help in addressing some of the currently open questions. This article is part of the theme issue ‘Fifty years of sperm competition’.
Collapse
Affiliation(s)
- Andreas Sutter
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Simone Immler
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| |
Collapse
|
14
|
Abstract
Cooperation has been essential to the evolution of biological complexity, but many societies struggle to overcome internal conflicts and divisions. Dictyostelium discoideum, or the social amoeba, has been a useful model system for exploring these conflicts and how they can be resolved. When starved, these cells communicate, gather into groups, and build themselves into a multicellular fruiting body. Some cells altruistically die to form the rigid stalk, while the remainder sit atop the stalk, become spores, and disperse. Evolutionary theory predicts that conflict will arise over which cells die to form the stalk and which cells become spores and survive. The power of the social amoeba lies in the ability to explore how cooperation and conflict work across multiple levels, ranging from proximate mechanisms (how does it work?) to ultimate evolutionary answers (why does it work?). Recent studies point to solutions to the problem of ensuring fairness, such as the ability to suppress selfishness and to recognize and avoid unrelated individuals. This work confirms a central role for kin selection, but also suggests new explanations for how social amoebae might enforce cooperation. New approaches based on genomics are also enabling researchers to decipher for the first time the evolutionary history of cooperation and conflict and to determine its role in shaping the biology of multicellular organisms.
Collapse
Affiliation(s)
- Elizabeth A Ostrowski
- School of Natural and Computational Sciences, Massey University, Auckland, New Zealand.
| |
Collapse
|
15
|
Wang Y, Rattray JB, Thomas SA, Gurney J, Brown SP. In silico bacteria evolve robust cooperaion via complex quorum-sensing strategies. Sci Rep 2020; 10:8628. [PMID: 32451396 PMCID: PMC7248119 DOI: 10.1038/s41598-020-65076-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 04/28/2020] [Indexed: 12/22/2022] Open
Abstract
Many species of bacteria collectively sense and respond to their social and physical environment via 'quorum sensing' (QS), a communication system controlling extracellular cooperative traits. Despite detailed understanding of the mechanisms of signal production and response, there remains considerable debate over the functional role(s) of QS: in short, what is it for? Experimental studies have found support for diverse functional roles: density sensing, mass-transfer sensing, genotype sensing, etc. While consistent with theory, these results cannot separate whether these functions were drivers of QS adaption, or simply artifacts or 'spandrels' of systems shaped by distinct ecological pressures. The challenge of separating spandrels from drivers of adaptation is particularly hard to address using extant bacterial species with poorly understood current ecologies (let alone their ecological histories). To understand the relationship between defined ecological challenges and trajectories of QS evolution, we used an agent-based simulation modeling approach. Given genetic mixing, our simulations produce behaviors that recapitulate features of diverse microbial QS systems, including coercive (high signal/low response) and generalized reciprocity (signal auto-regulation) strategists - that separately and in combination contribute to QS-dependent resilience of QS-controlled cooperation in the face of diverse cheats. We contrast our in silico results given defined ecological challenges with bacterial QS architectures that have evolved under largely unknown ecological contexts, highlighting the critical role of genetic constraints in shaping the shorter term (experimental evolution) dynamics of QS. More broadly, we see experimental evolution of digital organisms as a complementary tool in the search to understand the emergence of complex QS architectures and functions.
Collapse
Affiliation(s)
- Yifei Wang
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, 30332 GA, USA.
- The Institute for Data Engineering and Science (IDEaS), Georgia Institute of Technology, Atlanta, 30332 GA, USA.
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, 30332 GA, USA.
| | - Jennifer B Rattray
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, 30332 GA, USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, 30332 GA, USA
| | - Stephen A Thomas
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, 30332 GA, USA
- Graduate Program in Quantitative Biosciences (QBioS), Georgia Institute of Technology, Atlanta, 30332 GA, USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, 30332 GA, USA
| | - James Gurney
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, 30332 GA, USA
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, 30332 GA, USA
| | - Sam P Brown
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, 30332 GA, USA.
- Center for Microbial Dynamics and Infection, Georgia Institute of Technology, Atlanta, 30332 GA, USA.
| |
Collapse
|
16
|
Madgwick PG, Wolf JB. Evolution of strategic cooperation. Evol Lett 2020; 4:164-175. [PMID: 32313691 PMCID: PMC7156107 DOI: 10.1002/evl3.164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 01/23/2020] [Accepted: 02/02/2020] [Indexed: 11/30/2022] Open
Abstract
Group‐beneficial behaviors have presented a long‐standing challenge for evolutionary theory because, although their benefits are available to all group members, their costs are borne by individuals. Consequently, an individual could benefit from “cheating” their group mates by not paying the costs while still reaping the benefits. There have been many proposed evolutionary mechanisms that could favor cooperation (and disfavor cheating) in particular circumstances. However, if cooperation is still favored in some circumstances, then we might expect evolution to favor strategic cooperation, where the level of contribution toward group‐beneficial behavior is varied in response to the social context. To uncover how and why individuals should contribute toward group‐beneficial behavior across social contexts, we model strategic cooperation as an evolutionary game where players can quantitatively adjust the amount they contribute toward group‐beneficial behavior. We find that the evolutionarily stable strategy (ESS) predicts, unsurprisingly, that players should contribute in relation to their relatedness to the group. However, we surprisingly find that players often contribute to cooperation in such a way that their fitness is inverse to their relatedness to the group such that those that contribute to cooperation end up with the same return from group‐beneficial behavior, essentially removing any potential advantage of higher relatedness. These results bring to light a paradox of group‐beneficial cooperation: groups do best when they contain highly related individuals, but those with the highest relatedness to the group will often have the lowest fitness within the group.
Collapse
Affiliation(s)
- P G Madgwick
- Milner Centre for Evolution, Department of Biology and Biochemistry University of Bath Bath BA2 7AY United Kingdom
| | - J B Wolf
- Milner Centre for Evolution, Department of Biology and Biochemistry University of Bath Bath BA2 7AY United Kingdom
| |
Collapse
|
17
|
Abedon ST. Look Who's Talking: T-Even Phage Lysis Inhibition, the Granddaddy of Virus-Virus Intercellular Communication Research. Viruses 2019; 11:v11100951. [PMID: 31623057 PMCID: PMC6832632 DOI: 10.3390/v11100951] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/15/2019] [Accepted: 09/30/2019] [Indexed: 12/13/2022] Open
Abstract
That communication can occur between virus-infected cells has been appreciated for nearly as long as has virus molecular biology. The original virus communication process specifically was that seen with T-even bacteriophages-phages T2, T4, and T6-resulting in what was labeled as a lysis inhibition. Another proposed virus communication phenomenon, also seen with T-even phages, can be described as a phage-adsorption-induced synchronized lysis-inhibition collapse. Both are mediated by virions that were released from earlier-lysing, phage-infected bacteria. Each may represent ecological responses, in terms of phage lysis timing, to high local densities of phage-infected bacteria, but for lysis inhibition also to locally reduced densities of phage-uninfected bacteria. With lysis inhibition, the outcome is a temporary avoidance of lysis, i.e., a lysis delay, resulting in increased numbers of virions (greater burst size). Synchronized lysis-inhibition collapse, by contrast, is an accelerated lysis which is imposed upon phage-infected bacteria by virions that have been lytically released from other phage-infected bacteria. Here I consider some history of lysis inhibition, its laboratory manifestation, its molecular basis, how it may benefit expressing phages, and its potential ecological role. I discuss as well other, more recently recognized examples of virus-virus intercellular communication.
Collapse
Affiliation(s)
- Stephen T Abedon
- Department of Microbiology, The Ohio State University, Mansfield, OH 44906, USA.
| |
Collapse
|
18
|
Smith P, Cozart J, Lynn BK, Alberts E, Frangipani E, Schuster M. Bacterial Cheaters Evade Punishment by Cyanide. iScience 2019; 19:101-109. [PMID: 31357168 PMCID: PMC6664145 DOI: 10.1016/j.isci.2019.07.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/24/2019] [Accepted: 07/11/2019] [Indexed: 12/20/2022] Open
Abstract
In all domains of life, mechanisms exist that protect cooperating groups from exploitation by cheaters. Recent observations with the bacterium Pseudomonas aeruginosa have suggested a paradigmatic cheater control mechanism in which cooperator cells punish or "police" cheater cells by cyanide poisoning. These cheater cells are deficient in a pleiotropic quorum-sensing regulator that controls the production of cooperative secretions including cyanide, and presumably also cyanide resistance. In this study, we directly tested and refuted the cyanide policing model. Contrary to the hypothesis, cheater fitness was unaffected by the presence of cyanide. Cheater mutants grew equally well in co-cultures with either cyanide-proficient or cyanide-deficient cooperators, and they were as resistant to exogenous cyanide as wild-type cells. We show that these behaviors are the result of quorum-sensing-independent and cyanide-responsive resistance gene regulation. Our results highlight the role of genetic architecture in the evolution of cooperative behavior.
Collapse
Affiliation(s)
- Parker Smith
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
| | - Jamison Cozart
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
| | - Bryan K Lynn
- Department of Integrative Biology, Oregon State University, Corvallis, OR 97331, USA
| | - Erin Alberts
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA
| | - Emanuela Frangipani
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", 61029 Urbino (PU), Italy
| | - Martin Schuster
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA.
| |
Collapse
|
19
|
Miller JS, Reeve HK. Feedback loops in the major evolutionary transition to eusociality: the status and potential of theoretical approaches. CURRENT OPINION IN INSECT SCIENCE 2019; 34:85-90. [PMID: 31247424 DOI: 10.1016/j.cois.2019.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 04/19/2019] [Accepted: 04/25/2019] [Indexed: 06/09/2023]
Abstract
In this review, we adopt a step-wise framework for the evolution a major evolutionary transition in light of eusocial insects. By focusing on the sequence of (1) group formation, (2) alignment of genetic interests, and finally (3) group integration to higher-level functioning, we highlight that these steps occasionally interact with each other through feedback. We summarize models that capture such feedback and identify cases where there is room for the development of between-step relationships. We suggest that life history traits may serve as a conduit for analyzing feedback between suites of correlated traits. Our review reveals that there are many relationships both within and between the above steps that await formal modeling.
Collapse
Affiliation(s)
- Julie S Miller
- Ecology & Evolutionary Biology, University of California, Los Angeles, 612 Charles E. Young Dr., Los Angeles, CA 90095, USA.
| | - Hudson Kern Reeve
- Neurobiology & Behavior, Cornell University, 215 Tower Rd., Ithaca, NY 14850, USA
| |
Collapse
|
20
|
Bourke AF. Inclusive fitness and the major transitions in evolution. CURRENT OPINION IN INSECT SCIENCE 2019; 34:61-67. [PMID: 31247419 DOI: 10.1016/j.cois.2019.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/16/2019] [Accepted: 03/27/2019] [Indexed: 06/09/2023]
Abstract
Inclusive fitness theory is the leading framework for explaining the major transitions in evolution, whereby free-living subunits (e.g. cells, organisms) have cooperated to form new, higher-level units (e.g. organisms, eusocial societies). The theory has attracted considerable controversy. From a brief survey of the controversy's present status, I conclude that inclusive fitness theory continues to provide both a concept and a principled modelling tool of value for understanding social evolution, including major transitions. Turning to new developments in the study of major transitions, I describe work defining the point of occurrence of major transitions and, from inclusive fitness theory, the required conditions. I also suggest that it remains important to understand the evolution of individuality that occurs beyond such thresholds.
Collapse
Affiliation(s)
- Andrew Fg Bourke
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK.
| |
Collapse
|
21
|
Enforcement is central to the evolution of cooperation. Nat Ecol Evol 2019; 3:1018-1029. [PMID: 31239554 DOI: 10.1038/s41559-019-0907-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 04/26/2019] [Indexed: 01/21/2023]
Abstract
Cooperation occurs at all levels of life, from genomes, complex cells and multicellular organisms to societies and mutualisms between species. A major question for evolutionary biology is what these diverse systems have in common. Here, we review the full breadth of cooperative systems and find that they frequently rely on enforcement mechanisms that suppress selfish behaviour. We discuss many examples, including the suppression of transposable elements, uniparental inheritance of mitochondria and plastids, anti-cancer mechanisms, reciprocation and punishment in humans and other vertebrates, policing in eusocial insects and partner choice in mutualisms between species. To address a lack of accompanying theory, we develop a series of evolutionary models that show that the enforcement of cooperation is widely predicted. We argue that enforcement is an underappreciated, and often critical, ingredient for cooperation across all scales of biological organization.
Collapse
|
22
|
Wechsler T, Kümmerli R, Dobay A. Understanding policing as a mechanism of cheater control in cooperating bacteria. J Evol Biol 2019; 32:412-424. [PMID: 30724418 PMCID: PMC6520251 DOI: 10.1111/jeb.13423] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/30/2019] [Accepted: 01/31/2019] [Indexed: 12/17/2022]
Abstract
Policing occurs in insect, animal and human societies, where it evolved as a mechanism maintaining cooperation. Recently, it has been suggested that policing might even be relevant in enforcing cooperation in much simpler organisms such as bacteria. Here, we used individual-based modelling to develop an evolutionary concept for policing in bacteria and identify the conditions under which it can be adaptive. We modelled interactions between cooperators, producing a beneficial public good, cheaters, exploiting the public good without contributing to it, and public good-producing policers that secrete a toxin to selectively target cheaters. We found that toxin-mediated policing is favoured when (a) toxins are potent and durable, (b) toxins are cheap to produce, (c) cell and public good diffusion is intermediate, and (d) toxins diffuse farther than the public good. Although our simulations identify the parameter space where toxin-mediated policing can evolve, we further found that policing decays when the genetic linkage between public good and toxin production breaks. This is because policing is itself a public good, offering protection to toxin-resistant mutants that still produce public goods, yet no longer invest in toxins. Our work thus highlights that not only specific environmental conditions are required for toxin-mediated policing to evolve, but also strong genetic linkage between the expression of public goods, toxins and toxin resistance is essential for this mechanism to remain evolutionarily stable in the long run.
Collapse
Affiliation(s)
- Tobias Wechsler
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Rolf Kümmerli
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Akos Dobay
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
- Zurich Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| |
Collapse
|
23
|
Scott TW, Kiers ET, Cooper GA, dos Santos M, West SA. Evolutionary maintenance of genomic diversity within arbuscular mycorrhizal fungi. Ecol Evol 2019; 9:2425-2435. [PMID: 30891190 PMCID: PMC6405528 DOI: 10.1002/ece3.4834] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/23/2018] [Accepted: 11/26/2018] [Indexed: 01/12/2023] Open
Abstract
Most organisms are built from a single genome. In striking contrast, arbuscular mycorrhizal fungi appear to maintain genomic variation within an individual fungal network. Arbuscular mycorrhizal fungi dwell in the soil, form mutualistic networks with plants, and bear multiple, potentially genetically diverse nuclei within a network. We explore, from a theoretical perspective, why such genetic diversity might be maintained within individuals. We consider selection acting within and between individual fungal networks. We show that genetic diversity could provide a benefit at the level of the individual, by improving growth in variable environments, and that this can stabilize genetic diversity even in the presence of nuclear conflict. Arbuscular mycorrhizal fungi complicate our understanding of organismality, but our findings offer a way of understanding such biological anomalies.
Collapse
Affiliation(s)
| | - E. Toby Kiers
- Institute of Ecological Sciences, Faculty of Earth and Life SciencesVrije UniversiteitAmsterdamThe Netherlands
| | | | - Miguel dos Santos
- Department of ZoologyUniversity of OxfordOxfordUK
- Department of Social Psychology and Social Neuroscience, Institute of PsychologyUniversity of BernBernSwitzerland
| | - Stuart A. West
- Department of ZoologyUniversity of OxfordOxfordUK
- Magdalen CollegeOxfordUK
| |
Collapse
|
24
|
Abstract
The evolution in animals of a first possession convention, in which individuals retain what they are the first to acquire, has often been taken as a foundation for the evolution of human ownership institutions. However, among humans, individuals actually only seldom retain an item they have acquired from the environment, instead typically transferring what they possess to other members of the community, to those in command, or to those who hold a contractual title. This paper presents a novel game-theoretic model of the evolution of ownership institutions as rules governing resource transfers. Integrating existing findings, the model contributes a new perspective on the emergence of communal transfers among hominin large game hunters around 200,000 years ago, of command ownership among sedentary humans in the millennia prior to the transition to agriculture, and of titled property ownership around 5,500 years ago. Since today's property institutions motivate transfers through the promise of future returns, the analysis presented here suggests that these institutions may be placed under considerable pressure should resources become significantly constrained.
Collapse
Affiliation(s)
- Tilman Hartley
- School of Sociology, Politics, and International Studies, University of Bristol, Bristol, United Kingdom
| |
Collapse
|
25
|
Strategic investment explains patterns of cooperation and cheating in a microbe. Proc Natl Acad Sci U S A 2018; 115:E4823-E4832. [PMID: 29735672 DOI: 10.1073/pnas.1716087115] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Contributing to cooperation is typically costly, while its rewards are often available to all members of a social group. So why should individuals be willing to pay these costs, especially if they could cheat by exploiting the investments of others? Kin selection theory broadly predicts that individuals should invest more into cooperation if their relatedness to group members is high (assuming they can discriminate kin from nonkin). To better understand how relatedness affects cooperation, we derived the ‟Collective Investment" game, which provides quantitative predictions for patterns of strategic investment depending on the level of relatedness. We then tested these predictions by experimentally manipulating relatedness (genotype frequencies) in mixed cooperative aggregations of the social amoeba Dictyostelium discoideum, which builds a stalk to facilitate spore dispersal. Measurements of stalk investment by natural strains correspond to the predicted patterns of relatedness-dependent strategic investment, wherein investment by a strain increases with its relatedness to the group. Furthermore, if overall group relatedness is relatively low (i.e., no strain is at high frequency in a group) strains face a scenario akin to the "Prisoner's Dilemma" and suffer from insufficient collective investment. We find that strains employ relatedness-dependent segregation to avoid these pernicious conditions. These findings demonstrate that simple organisms like D. discoideum are not restricted to being ‟cheaters" or ‟cooperators" but instead measure their relatedness to their group and strategically modulate their investment into cooperation accordingly. Consequently, all individuals will sometimes appear to cooperate and sometimes cheat due to the dynamics of strategic investing.
Collapse
|
26
|
Radzvilavicius AL, Blackstone NW. The evolution of individuality revisited. Biol Rev Camb Philos Soc 2018; 93:1620-1633. [DOI: 10.1111/brv.12412] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Revised: 02/21/2018] [Accepted: 02/28/2018] [Indexed: 12/28/2022]
Affiliation(s)
| | - Neil W. Blackstone
- Department of Biological Sciences; Northern Illinois University; DeKalb IL 60115 U.S.A
| |
Collapse
|
27
|
Maintenance of Microbial Cooperation Mediated by Public Goods in Single- and Multiple-Trait Scenarios. J Bacteriol 2017; 199:JB.00297-17. [PMID: 28847922 DOI: 10.1128/jb.00297-17] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Microbes often form densely populated communities, which favor competitive and cooperative interactions. Cooperation among bacteria often occurs through the production of metabolically costly molecules produced by certain individuals that become available to other neighboring individuals; such molecules are called public goods. This type of cooperation is susceptible to exploitation, since nonproducers of a public good can benefit from it while saving the cost of its production (cheating), gaining a fitness advantage over producers (cooperators). Thus, in mixed cultures, cheaters can increase in frequency in the population, relative to cooperators. Sometimes, and as predicted by simple game-theoretic arguments, such increases in the frequency of cheaters cause loss of the cooperative traits by exhaustion of the public goods, eventually leading to a collapse of the entire population. In other cases, however, both cooperators and cheaters remain in coexistence. This raises the question of how cooperation is maintained in microbial populations. Several strategies to prevent cheating have been studied in the context of a single trait and a unique environmental constraint. In this review, we describe current knowledge on the evolutionary stability of microbial cooperation and discuss recent discoveries describing the mechanisms operating in multiple-trait and multiple-constraint settings. We conclude with a consideration of the consequences of these complex interactions, and we briefly discuss the potential role of social interactions involving multiple traits and multiple environmental constraints in the evolution of specialization and division of labor in microbes.
Collapse
|
28
|
Graves CJ, Weinreich DM. Variability in fitness effects can preclude selection of the fittest. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2017; 48:399-417. [PMID: 31572069 DOI: 10.1146/annurev-ecolsys-110316-022722] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Evolutionary biologists often predict the outcome of natural selection on an allele by measuring its effects on lifetime survival and reproduction of individual carriers. However, alleles affecting traits like sex, evolvability, and cooperation can cause fitness effects that depend heavily on differences in the environmental, social, and genetic context of individuals carrying the allele. This variability makes it difficult to summarize the evolutionary fate of an allele based solely on its effects on any one individual. Attempts to average over this variability can sometimes salvage the concept of fitness. In other cases evolutionary outcomes can only be predicted by considering the entire genealogy of an allele, thus limiting the utility of individual fitness altogether. We describe a number of intriguing new evolutionary phenomena that have emerged in studies that explicitly model long-term lineage dynamics and discuss implications for the evolution of infectious diseases.
Collapse
Affiliation(s)
- Christopher J Graves
- Brown University, Department of Ecology and Evolutionary Biology and Center for Computational and Molecular Biology. Providence, RI, USA
| | - Daniel M Weinreich
- Brown University, Department of Ecology and Evolutionary Biology and Center for Computational and Molecular Biology. Providence, RI, USA
| |
Collapse
|
29
|
Domingues IL, Gama JA, Carvalho LM, Dionisio F. Social behaviour involving drug resistance: the role of initial density, initial frequency and population structure in shaping the effect of antibiotic resistance as a public good. Heredity (Edinb) 2017. [PMID: 28635967 DOI: 10.1038/hdy.2017.33] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Bacteria sometimes cooperate with co-inhabiting cells. Pathogenic bacteria, for example, often produce and excrete virulence factors, eventually benefitting both producer and non-producer cells. The role of social interactions involving antibiotic resistance, however, has been more elusive. Enzymes that inactivate β-lactam antibiotics such as ampicillin or penicillin (β-lactamases) are good candidates as public goods. Nonetheless, it has been claimed that bacteria harbouring plasmids of natural origin coding for β-lactamase almost do not protect sensitive bacteria. This does not fit with the fact that ampicillin-sensitive bacteria can be isolated from subjects undergoing ampicillin treatment. We hypothesised that there are two non-exclusive explanations for the discrepancy between previous works: (1) the range of values of demographic conditions (such as initial strain frequency, initial total cell density or habitat structure) has not been broad enough to include most scenarios, or (2) there are interactions between some of these factors. We performed experiments with Escherichia coli bacterial cells to measure the degree of protection of sensitive cells when co-cultured with cells harbouring RP4, R16a or the R1 plasmids, all of natural origin and coding for β-lactamases, and in presence of ampicillin. In these co-cultures, performed in structured and non-structured environments, both the initial total cell density and the initial frequency of sensitive cells spanned four orders of magnitude. We found protection of sensitive cells in 63% of tested conditions. All factors (plasmid, structure, frequency and density) significantly affect levels of protection. Moreover, all factors interact, with interactions revealing large or very large effect sizes.
Collapse
Affiliation(s)
- I L Domingues
- Departamento de Biologia Vegetal, Faculdade de Ciências, CE3C-Centre for Ecology, Evolution and Environmental Changes, Universidade de Lisboa, Lisbon, Portugal.,Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - J A Gama
- Departamento de Biologia Vegetal, Faculdade de Ciências, CE3C-Centre for Ecology, Evolution and Environmental Changes, Universidade de Lisboa, Lisbon, Portugal.,Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - L M Carvalho
- Departamento de Biologia Vegetal, Faculdade de Ciências, CE3C-Centre for Ecology, Evolution and Environmental Changes, Universidade de Lisboa, Lisbon, Portugal
| | - F Dionisio
- Departamento de Biologia Vegetal, Faculdade de Ciências, CE3C-Centre for Ecology, Evolution and Environmental Changes, Universidade de Lisboa, Lisbon, Portugal.,Instituto Gulbenkian de Ciência, Oeiras, Portugal
| |
Collapse
|
30
|
Schuster M, Sexton DJ, Hense BA. Why Quorum Sensing Controls Private Goods. Front Microbiol 2017; 8:885. [PMID: 28579979 PMCID: PMC5437708 DOI: 10.3389/fmicb.2017.00885] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 05/02/2017] [Indexed: 12/22/2022] Open
Abstract
Cell-cell communication, also termed quorum sensing (QS), is a widespread process that coordinates gene expression in bacterial populations. The generally accepted view is that QS optimizes the cell density-dependent benefit attained from cooperative behaviors, often in the form of secreted products referred to as "public goods." This view is challenged by an increasing number of cell-associated products or "private goods" reported to be under QS-control for which a collective benefit is not apparent. A prominent example is nucleoside hydrolase from Pseudomonas aeruginosa, a periplasmic enzyme that catabolizes adenosine. Several recent studies have shown that private goods can function to stabilize cooperation by co-regulated public goods, seemingly explaining their control by QS. Here we argue that this property is a by-product of selection for other benefits rather than an adaptation. Emphasizing ecophysiological context, we propose alternative explanations for the QS control of private goods. We suggest that the benefit attained from private goods is associated with high cell density, either because a relevant ecological condition correlates with density, or because the private good is, directly or indirectly, involved in cooperative behavior. Our analysis helps guide a systems approach to QS, with implications for antivirulence drug design and synthetic biology.
Collapse
Affiliation(s)
- Martin Schuster
- Department of Microbiology, Oregon State UniversityCorvallis, OR, United States
| | - D Joseph Sexton
- Department of Microbiology, Oregon State UniversityCorvallis, OR, United States
| | - Burkhard A Hense
- Institute of Computational Biology, Helmholtz Zentrum MünchenNeuherberg, Germany
| |
Collapse
|
31
|
Chao L, Elena SF. Nonlinear trade-offs allow the cooperation game to evolve from Prisoner's Dilemma to Snowdrift. Proc Biol Sci 2017; 284:20170228. [PMID: 28490625 PMCID: PMC5443946 DOI: 10.1098/rspb.2017.0228] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 04/10/2017] [Indexed: 01/21/2023] Open
Abstract
The existence of cooperation, or the production of public goods, is an evolutionary problem. Cooperation is not favoured because the Prisoner's Dilemma (PD) game drives cooperators to extinction. We have re-analysed this problem by using RNA viruses to motivate a model for the evolution of cooperation. Gene products are the public goods and group size is the number of virions co-infecting the same host cell. Our results show that if the trade-off between replication and production of gene products is linear, PD is observed. However, if the trade-off is nonlinear, the viruses evolve into separate lineages of ultra-defectors and ultra-cooperators as group size is increased. The nonlinearity was justified by the existence of real viral ultra-defectors, known as defective interfering particles, which gain a nonlinear advantage by being smaller. The evolution of ultra-defectors and ultra-cooperators creates the Snowdrift game, which promotes high-level production of public goods.
Collapse
Affiliation(s)
- Lin Chao
- Section of Ecology, Behavior and Evolution, Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093-0116, USA
| | - Santiago F Elena
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, Ingeniero Fausto Elio s/n, 46022 Valencia, Spain
- Instituto de Biología Integrativa y de Sistemas (ISysBio), Consejo Superior de Investigaciones Científicas-Universitat de València, Catedrático Agustín Escardino 9, 46182 Paterna, Valencia, Spain
- The Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA
| |
Collapse
|
32
|
Kamel SJ, Williams PD. Resource exploitation and relatedness: implications for offspring size variation within broods. OIKOS 2017. [DOI: 10.1111/oik.04034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stephanie J. Kamel
- Dept of Biology and Marine Biology, Center for Marine Science; Univ. of North Carolina Wilmington; 601 S. College Rd. Wilmington, NC 28403 USA
| | - Paul D. Williams
- Dept of Biology and Marine Biology, Center for Marine Science; Univ. of North Carolina Wilmington; 601 S. College Rd. Wilmington, NC 28403 USA
| |
Collapse
|
33
|
Kurokawa S, Ihara Y. Evolution of group-wise cooperation: Is direct reciprocity insufficient? J Theor Biol 2017; 415:20-31. [DOI: 10.1016/j.jtbi.2016.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 09/26/2016] [Accepted: 12/05/2016] [Indexed: 11/30/2022]
|
34
|
Riehl C, Frederickson ME. Cheating and punishment in cooperative animal societies. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150090. [PMID: 26729930 DOI: 10.1098/rstb.2015.0090] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Cheaters-genotypes that gain a selective advantage by taking the benefits of the social contributions of others while avoiding the costs of cooperating-are thought to pose a major threat to the evolutionary stability of cooperative societies. In order for cheaters to undermine cooperation, cheating must be an adaptive strategy: cheaters must have higher fitness than cooperators, and their behaviour must reduce the fitness of their cooperative partners. It is frequently suggested that cheating is not adaptive because cooperators have evolved mechanisms to punish these behaviours, thereby reducing the fitness of selfish individuals. However, a simpler hypothesis is that such societies arise precisely because cooperative strategies have been favoured over selfish ones-hence, behaviours that have been interpreted as 'cheating' may not actually result in increased fitness, even when they go unpunished. Here, we review the empirical evidence for cheating behaviours in animal societies, including cooperatively breeding vertebrates and social insects, and we ask whether such behaviours are primarily limited by punishment. Our review suggests that both cheating and punishment are probably rarer than often supposed. Uncooperative individuals typically have lower, not higher, fitness than cooperators; and when evidence suggests that cheating may be adaptive, it is often limited by frequency-dependent selection rather than by punishment. When apparently punitive behaviours do occur, it remains an open question whether they evolved in order to limit cheating, or whether they arose before the evolution of cooperation.
Collapse
Affiliation(s)
- Christina Riehl
- Department of Ecology and Evolutionary Biology, Princeton University, 106A Guyot Hall, Princeton, NJ 08544, USA
| | - Megan E Frederickson
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2
| |
Collapse
|
35
|
Schuster P. Some mechanistic requirements for major transitions. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150439. [PMID: 27431517 PMCID: PMC4958933 DOI: 10.1098/rstb.2015.0439] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2016] [Indexed: 12/19/2022] Open
Abstract
Major transitions in nature and human society are accompanied by a substantial change towards higher complexity in the core of the evolving system. New features are established, novel hierarchies emerge, new regulatory mechanisms are required and so on. An obvious way to achieve higher complexity is integration of autonomous elements into new organized systems whereby the previously independent units give up their autonomy at least in part. In this contribution, we reconsider the more than 40 years old hypercycle model and analyse it by the tools of stochastic chemical kinetics. An open system is implemented in the form of a flow reactor. The formation of new dynamically organized units through integration of competitors is identified with transcritical bifurcations. In the stochastic model, the fully organized state is quasi-stationary whereas the unorganized state corresponds to a population with natural selection. The stability of the organized state depends strongly on the number of individual subspecies, n, that have to be integrated: two and three classes of individuals, [Formula: see text] and [Formula: see text], readily form quasi-stationary states. The four-membered deterministic dynamical system, [Formula: see text], is stable but in the stochastic approach self-enhancing fluctuations drive it into extinction. In systems with five and more classes of individuals, [Formula: see text], the state of cooperation is unstable and the solutions of the deterministic ODEs exhibit large amplitude oscillations. In the stochastic system self-enhancing fluctuations lead to extinction as observed with [Formula: see text] Interestingly, cooperative systems in nature are commonly two-membered as shown by numerous examples of binary symbiosis. A few cases of symbiosis of three partners, called three-way symbiosis, have been found and were analysed within the past decade. Four-way symbiosis is rather rare but was reported to occur in fungus-growing ants. The model reported here can be used to illustrate the interplay between competition and cooperation whereby we obtain a hint on the role that resources play in major transitions. Abundance of resources seems to be an indispensable prerequisite of radical innovation that apparently needs substantial investments. Economists often claim that scarcity is driving innovation. Our model sheds some light on this apparent contradiction. In a nutshell, the answer is: scarcity drives optimization and increase in efficiency but abundance is required for radical novelty and the development of new features.This article is part of the themed issue 'The major synthetic evolutionary transitions'.
Collapse
Affiliation(s)
- Peter Schuster
- Institut für Theoretische Chemie, Universität Wien, Währingerstraße 17 1090 Wien, Austria Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA
| |
Collapse
|
36
|
The four elements of within-group conflict in animal societies: an experimental test using the clown anemonefish, Amphiprion percula. Behav Ecol Sociobiol 2016. [DOI: 10.1007/s00265-016-2155-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
37
|
Sociable Weavers Increase Cooperative Nest Construction after Suffering Aggression. PLoS One 2016; 11:e0150953. [PMID: 26982704 PMCID: PMC4794138 DOI: 10.1371/journal.pone.0150953] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 02/22/2016] [Indexed: 11/19/2022] Open
Abstract
The major transitions in evolution rely on the formation of stable groups that are composed of previously independent units, and the stability of these groups requires both cooperation and reduced conflict. Conflict over group resources may be common, as suggested by work in both cichlids and humans that has investigated how societies resolve conflict regarding investment in group resources, i.e. public goods. We investigated whether sociable weavers (Philetairus socius) use aggressive behaviors to modulate the cooperative behavior of group mates. We find that the individuals that build the communal thatch of the nest, i.e. the individuals most at risk of exploitation, are the most aggressive individuals. We show that individuals that invest in interior chamber maintenance, possibly a more selfish behavior, suffer relatively more aggression. After suffering aggression individuals significantly increase cooperative construction of the communal nest thatch. We show that cooperative individuals target aggression towards selfish individuals, and the individuals suffering aggression perform cooperative behaviors subsequent to suffering aggression. In addition to other evolutionary mechanisms, these results suggest that aggression, possibly via the pay-to-stay mechanism, is possibly being used to maintain a public good.
Collapse
|
38
|
Gavrilets S. Collective action problem in heterogeneous groups. Philos Trans R Soc Lond B Biol Sci 2015; 370:20150016. [PMID: 26503689 PMCID: PMC4633852 DOI: 10.1098/rstb.2015.0016] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2015] [Indexed: 11/12/2022] Open
Abstract
I review the theoretical and experimental literature on the collective action problem in groups whose members differ in various characteristics affecting individual costs, benefits and preferences in collective actions. I focus on evolutionary models that predict how individual efforts and fitnesses, group efforts and the amount of produced collective goods depend on the group's size and heterogeneity, as well as on the benefit and cost functions and parameters. I consider collective actions that aim to overcome the challenges from nature or win competition with neighbouring groups of co-specifics. I show that the largest contributors towards production of collective goods will typically be group members with the highest stake in it or for whom the effort is least costly, or those who have the largest capability or initial endowment. Under some conditions, such group members end up with smaller net pay-offs than the rest of the group. That is, they effectively behave as altruists. With weak nonlinearity in benefit and cost functions, the group effort typically decreases with group size and increases with within-group heterogeneity. With strong nonlinearity in benefit and cost functions, these patterns are reversed. I discuss the implications of theoretical results for animal behaviour, human origins and psychology.
Collapse
Affiliation(s)
- Sergey Gavrilets
- Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996, USA Department of Mathematics, University of Tennessee, Knoxville, TN 37996, USA National Institute for Mathematical and Biological Synthesis, University of Tennessee, Knoxville, TN 37996, USA
| |
Collapse
|
39
|
Abstract
With the increasing appreciation for the crucial roles that microbial symbionts play in the development and fitness of plant and animal hosts, there has been a recent push to interpret evolution through the lens of the "hologenome"--the collective genomic content of a host and its microbiome. But how symbionts evolve and, particularly, whether they undergo natural selection to benefit hosts are complex issues that are associated with several misconceptions about evolutionary processes in host-associated microbial communities. Microorganisms can have intimate, ancient, and/or mutualistic associations with hosts without having undergone natural selection to benefit hosts. Likewise, observing host-specific microbial community composition or greater community similarity among more closely related hosts does not imply that symbionts have coevolved with hosts, let alone that they have evolved for the benefit of the host. Although selection at the level of the symbiotic community, or hologenome, occurs in some cases, it should not be accepted as the null hypothesis for explaining features of host-symbiont associations.
Collapse
|
40
|
Privatization of cooperative benefits stabilizes mutualistic cross-feeding interactions in spatially structured environments. ISME JOURNAL 2015; 10:1413-23. [PMID: 26623546 DOI: 10.1038/ismej.2015.212] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 09/27/2015] [Accepted: 10/01/2015] [Indexed: 01/22/2023]
Abstract
Metabolic cross-feeding interactions are ubiquitous in natural microbial communities. However, it remains generally unclear whether the production and exchange of metabolites incurs fitness costs to the producing cells and if so, which ecological mechanisms can facilitate a cooperative exchange of metabolites among unrelated individuals. We hypothesized that positive assortment within structured environments can maintain mutualistic cross-feeding. To test this, we engineered Acinetobacter baylyi and Escherichia coli to reciprocally exchange essential amino acids. Interspecific coculture experiments confirmed that non-cooperating types were selectively favoured in spatially unstructured (liquid culture), yet disfavoured in spatially structured environments (agar plates). Both an individual-based model and experiments with engineered genotypes indicated that a segregation of cross-feeders and non-cooperating auxotrophs stabilized cooperative cross-feeding in spatially structured environments. Chemical imaging confirmed that auxotrophs were spatially excluded from cooperative benefits. Together, these results demonstrate that cooperative cross-feeding between different bacterial species is favoured in structured environments such as bacterial biofilms, suggesting this type of interactions might be common in natural bacterial communities.
Collapse
|
41
|
Smith JE, Gavrilets S, Mulder MB, Hooper PL, Mouden CE, Nettle D, Hauert C, Hill K, Perry S, Pusey AE, van Vugt M, Smith EA. Leadership in Mammalian Societies: Emergence, Distribution, Power, and Payoff. Trends Ecol Evol 2015; 31:54-66. [PMID: 26552515 DOI: 10.1016/j.tree.2015.09.013] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 09/10/2015] [Accepted: 09/23/2015] [Indexed: 11/25/2022]
Abstract
Leadership is an active area of research in both the biological and social sciences. This review provides a transdisciplinary synthesis of biological and social-science views of leadership from an evolutionary perspective, and examines patterns of leadership in a set of small-scale human and non-human mammalian societies. We review empirical and theoretical work on leadership in four domains: movement, food acquisition, within-group conflict mediation, and between-group interactions. We categorize patterns of variation in leadership in five dimensions: distribution (across individuals), emergence (achieved versus inherited), power, relative payoff to leadership, and generality (across domains). We find that human leadership exhibits commonalities with and differences from the broader mammalian pattern, raising interesting theoretical and empirical issues.
Collapse
Affiliation(s)
| | - Sergey Gavrilets
- Department of Ecology and Evolutionary Biology, and Department of Mathematics, University of Tennessee, and National Institute for Mathematical and Biological Synthesis, Knoxville, TN 37996, USA
| | - Monique Borgerhoff Mulder
- Department of Anthropology, and Center for Population Biology, University of California at Davis, Davis, CA 95616, USA
| | - Paul L Hooper
- Department of Anthropology, Emory University, Atlanta, GA 30322, USA
| | | | - Daniel Nettle
- Centre for Behavior and Evolution, and Institute of Neuroscience, Newcastle University, Newcastle NE2 4HH, UK
| | - Christoph Hauert
- Departments of Mathematics and Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Kim Hill
- Institute for Human Origins, and School of Human Evolution and Social Change, Arizona State University, Tempe, AZ 85281, USA
| | - Susan Perry
- Department of Anthropology, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Anne E Pusey
- Department of Evolutionary Anthropology, Duke University, Durham, NC 27708, USA
| | - Mark van Vugt
- Department of Experimental and Applied Psychology, VU University Amsterdam, the Netherlands; Institute for Cognitive and Evolutionary Anthropology, University of Oxford, UK
| | - Eric Alden Smith
- Department of Anthropology, University of Washington, Seattle, WA 98195-3100, USA.
| |
Collapse
|
42
|
Leighton GM, Echeverri S, Heinrich D, Kolberg H. Relatedness predicts multiple measures of investment in cooperative nest construction in sociable weavers. Behav Ecol Sociobiol 2015; 69:1835-1843. [PMID: 26726282 PMCID: PMC4693614 DOI: 10.1007/s00265-015-1996-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Although communal goods are often critical to society, they are simultaneously susceptible to exploitation and are evolutionarily stable only if mechanisms exist to curtail exploitation. Mechanisms such as punishment and kin selection have been offered as general explanations for how communal resources can be maintained. Evidence for these mechanisms comes largely from humans and social insects, leaving their generality in question. To assess how communal resources are maintained, we observed cooperative nest construction in sociable weavers (Philetairus socius). The communal nest of sociable weavers provides thermal benefits for all individuals but requires continual maintenance. We observed cooperative nest construction and also recorded basic morphological characteristics. We also collected blood samples, performed next-generation sequencing, and isolated 2358 variable single nucleotide polymorphisms (SNPs) to estimate relatedness. We find that relatedness predicts investment in cooperative nest construction, while no other morphological characters significantly explain cooperative output. We argue that indirect benefits are a critical fitness component for maintaining the cooperative behavior that maintains the communal good.
Collapse
Affiliation(s)
- Gavin M. Leighton
- Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA
| | - Sebastian Echeverri
- Department of Ecology and Evolution, University of Pittsburgh, Pittsburgh, PA, USA
| | | | | |
Collapse
|
43
|
West SA, Fisher RM, Gardner A, Kiers ET. Major evolutionary transitions in individuality. Proc Natl Acad Sci U S A 2015; 112:10112-9. [PMID: 25964342 PMCID: PMC4547252 DOI: 10.1073/pnas.1421402112] [Citation(s) in RCA: 180] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The evolution of life on earth has been driven by a small number of major evolutionary transitions. These transitions have been characterized by individuals that could previously replicate independently, cooperating to form a new, more complex life form. For example, archaea and eubacteria formed eukaryotic cells, and cells formed multicellular organisms. However, not all cooperative groups are en route to major transitions. How can we explain why major evolutionary transitions have or haven't taken place on different branches of the tree of life? We break down major transitions into two steps: the formation of a cooperative group and the transformation of that group into an integrated entity. We show how these steps require cooperation, division of labor, communication, mutual dependence, and negligible within-group conflict. We find that certain ecological conditions and the ways in which groups form have played recurrent roles in driving multiple transitions. In contrast, we find that other factors have played relatively minor roles at many key points, such as within-group kin discrimination and mechanisms to actively repress competition. More generally, by identifying the small number of factors that have driven major transitions, we provide a simpler and more unified description of how life on earth has evolved.
Collapse
Affiliation(s)
- Stuart A West
- Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom; Magdalen College, Oxford OX1 4AU, United Kingdom;
| | - Roberta M Fisher
- Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom
| | - Andy Gardner
- School of Biology, University of St. Andrews, Dyers Brae, St. Andrews KY16 9TH, United Kingdom; and
| | - E Toby Kiers
- Institute of Ecological Sciences, Faculty of Earth and Life Sciences, Vrije Universiteit, 1081 HV, Amsterdam, The Netherlands
| |
Collapse
|
44
|
Nunney L, Maley CC, Breen M, Hochberg ME, Schiffman JD. Peto's paradox and the promise of comparative oncology. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140177. [PMID: 26056361 PMCID: PMC4581022 DOI: 10.1098/rstb.2014.0177] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/29/2015] [Indexed: 02/06/2023] Open
Abstract
The past several decades have seen a paradigm shift with the integration of evolutionary thinking into studying cancer. The evolutionary lens is most commonly employed in understanding cancer emergence, tumour growth and metastasis, but there is an increasing realization that cancer defences both between tissues within the individual and between species have been influenced by natural selection. This special issue focuses on discoveries of these deeper evolutionary phenomena in the emerging area of 'comparative oncology'. Comparing cancer dynamics in different tissues or species can lead to insights into how biology and ecology have led to differences in carcinogenesis, and the diversity, incidence and lethality of cancers. In this introduction to the special issue, we review the history of the field and outline how the contributions use empirical, comparative and theoretical approaches to address the processes and patterns associated with 'Peto's paradox', the lack of a statistical relationship of cancer incidence with body size and longevity. This burgeoning area of research can help us understand that cancer is not only a disease but is also a driving force in biological systems and species life histories. Comparative oncology will be key to understanding globally important health issues, including cancer epidemiology, prevention and improved therapies.
Collapse
Affiliation(s)
- Leonard Nunney
- Department of Biology, University of California Riverside, CA 92521, USA
| | - Carlo C Maley
- Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA Center for Evolution and Cancer, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA 94143, USA Centre for Evolution and Cancer, Institute for Cancer Research, London, UK
| | - Matthew Breen
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27695, USA Center for Comparative Medicine and Translational Research, North Carolina State University, Raleigh, NC 27695, USA Center for Human Health and the Environment, North Carolina State University, Raleigh, NC 27695, USA Genetics Program, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27514, USA
| | - Michael E Hochberg
- Institut des Sciences de l'Evolution, Université Montpellier, UMR5554 du CNRS, Montpellier 34095, France Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA
| | - Joshua D Schiffman
- Primary Children's Hospital (Intermountain Healthcare) and Huntsman Cancer Institute, Departments of Pediatrics and Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| |
Collapse
|
45
|
Peña J, Nöldeke G, Lehmann L. Evolutionary dynamics of collective action in spatially structured populations. J Theor Biol 2015; 382:122-36. [PMID: 26151588 DOI: 10.1016/j.jtbi.2015.06.039] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 06/22/2015] [Accepted: 06/24/2015] [Indexed: 01/09/2023]
Abstract
Many models proposed to study the evolution of collective action rely on a formalism that represents social interactions as n-player games between individuals adopting discrete actions such as cooperate and defect. Despite the importance of spatial structure in biological collective action, the analysis of n-player games games in spatially structured populations has so far proved elusive. We address this problem by considering mixed strategies and by integrating discrete-action n-player games into the direct fitness approach of social evolution theory. This allows to conveniently identify convergence stable strategies and to capture the effect of population structure by a single structure coefficient, namely, the pairwise (scaled) relatedness among interacting individuals. As an application, we use our mathematical framework to investigate collective action problems associated with the provision of three different kinds of collective goods, paradigmatic of a vast array of helping traits in nature: "public goods" (both providers and shirkers can use the good, e.g., alarm calls), "club goods" (only providers can use the good, e.g., participation in collective hunting), and "charity goods" (only shirkers can use the good, e.g., altruistic sacrifice). We show that relatedness promotes the evolution of collective action in different ways depending on the kind of collective good and its economies of scale. Our findings highlight the importance of explicitly accounting for relatedness, the kind of collective good, and the economies of scale in theoretical and empirical studies of the evolution of collective action.
Collapse
Affiliation(s)
- Jorge Peña
- Department of Evolutionary Theory, Max Planck Institute for Evolutionary Biology, August-Thienemann-Str. 2, 24306 Plön, Germany.
| | - Georg Nöldeke
- Faculty of Business and Economics, University of Basel, Peter Merian-Weg 6, 4002 Basel, Switzerland.
| | - Laurent Lehmann
- Department of Ecology and Evolution, University of Lausanne, Le Biophore, 1015 Lausanne, Switzerland.
| |
Collapse
|
46
|
Ducasse H, Arnal A, Vittecoq M, Daoust SP, Ujvari B, Jacqueline C, Tissot T, Ewald P, Gatenby RA, King KC, Bonhomme F, Brodeur J, Renaud F, Solary E, Roche B, Thomas F. Cancer: an emergent property of disturbed resource-rich environments? Ecology meets personalized medicine. Evol Appl 2015; 8:527-40. [PMID: 26136819 PMCID: PMC4479509 DOI: 10.1111/eva.12232] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 10/17/2015] [Indexed: 12/13/2022] Open
Abstract
For an increasing number of biologists, cancer is viewed as a dynamic system governed by evolutionary and ecological principles. Throughout most of human history, cancer was an uncommon cause of death and it is generally accepted that common components of modern culture, including increased physiological stresses and caloric intake, favor cancer development. However, the precise mechanisms for this linkage are not well understood. Here, we examine the roles of ecological and physiological disturbances and resource availability on the emergence of cancer in multicellular organisms. We argue that proliferation of 'profiteering phenotypes' is often an emergent property of disturbed, resource-rich environments at all scales of biological organization. We review the evidence for this phenomenon, explore it within the context of malignancy, and discuss how this ecological framework may offer a theoretical background for novel strategies of cancer prevention. This work provides a compelling argument that the traditional separation between medicine and evolutionary ecology remains a fundamental limitation that needs to be overcome if complex processes, such as oncogenesis, are to be completely understood.
Collapse
Affiliation(s)
- Hugo Ducasse
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
| | - Audrey Arnal
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
| | - Marion Vittecoq
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
- Centre de Recherche de la Tour du ValatArles, France
| | - Simon P Daoust
- Department of Biology, John Abbott CollegeSainte-Anne-de-Bellevue, QC, Canada
| | - Beata Ujvari
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin UniversityWaurn Ponds, Vic., Australia
| | - Camille Jacqueline
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
| | - Tazzio Tissot
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
| | - Paul Ewald
- Department of Biology and the Program on Disease Evolution, University of LouisvilleLouisville, KY, USA
| | - Robert A Gatenby
- Department of Radiology, H. Lee Moffitt Cancer Center & Research InstituteTampa, FL, USA
| | - Kayla C King
- Department of Zoology, University of OxfordOxford, UK
| | - François Bonhomme
- ISEM Institut des sciences de l'évolution, Université Montpellier 2, CNRS/IRD/UM2 UMR 5554Montpellier Cedex, France
| | - Jacques Brodeur
- Institut de Recherche en Biologie Végétale, Université de MontréalMontréal, QC, Canada
| | - François Renaud
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
| | - Eric Solary
- INSERM U1009, Université Paris-Sud, Gustave RoussyVillejuif, France
| | - Benjamin Roche
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
- Unité mixte internationale de Modélisation Mathématique et Informatique des Systèmes Complexes (UMI IRD/UPMC UMMISCO)BondyCedex, France
| | - Frédéric Thomas
- MIVEGEC, UMR IRD/CNRS/UM 5290Montpellier Cedex 5, France
- CREEC, Université Montpellier 2Montpellier Cedex 5, France
| |
Collapse
|
47
|
Affiliation(s)
- Manvir Singh
- Centre for Social Evolution, Dept of Biology; Univ. of Copenhagen; Universitetsparken 15 DK-2100 Copenhagen Denmark
| | - Jacobus J. Boomsma
- Centre for Social Evolution, Dept of Biology; Univ. of Copenhagen; Universitetsparken 15 DK-2100 Copenhagen Denmark
| |
Collapse
|
48
|
Spatial heterogeneity and host repression in fig-fig wasp mutualism. SCIENCE CHINA-LIFE SCIENCES 2015; 58:492-500. [PMID: 25863497 DOI: 10.1007/s11427-015-4848-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 03/03/2015] [Indexed: 10/23/2022]
Abstract
It is generally believed that physical heterogeneity in common resource or evolutionary restraint can sufficiently prevent direct conflict between host and symbionts in mutualism systems. Our data on fig/fig wasp reciprocal mutualism (Ficus racemosa), however, show that structural barriers of female flowers or genetic constraints of pollinators previously hypothesized exist, but cannot sufficiently maintain the mutualism stability. The results show that a positive relationship between seed and wasp production could be maintained in warm season, which might be because of density dependence restraint among foundresses and their low oviposition and pollination efficiency, keeping common resource (female flowers) utilization unsaturated. Whilst, a negative correlation between wasp offspring and viable seed production was also observed in cold season, which might be that the increased oviposition and pollination efficiency maximized the common resource utilization. The fitness trade-off between fig and pollinator wasps is greatly affected by environmental or ecological variations. The local stability might result from temporal low exploitation efficiency of pollinators together with interference competition among pollinators. We suggest that host repression through the active regulation of bract closure, which can create interference competition among the foundresses and prevent extra more foundresses sequential entry in fruit cavities, would help the figs avoiding the cost of over-exploitation. This essentially takes the same role as sanctioning of cheating or competitive behaviors.
Collapse
|
49
|
Liao X, Rong S, Queller DC. Relatedness, conflict, and the evolution of eusociality. PLoS Biol 2015; 13:e1002098. [PMID: 25799485 PMCID: PMC4370713 DOI: 10.1371/journal.pbio.1002098] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 02/10/2015] [Indexed: 11/28/2022] Open
Abstract
The evolution of sterile worker castes in eusocial insects was a major problem in evolutionary theory until Hamilton developed a method called inclusive fitness. He used it to show that sterile castes could evolve via kin selection, in which a gene for altruistic sterility is favored when the altruism sufficiently benefits relatives carrying the gene. Inclusive fitness theory is well supported empirically and has been applied to many other areas, but a recent paper argued that the general method of inclusive fitness was wrong and advocated an alternative population genetic method. The claim of these authors was bolstered by a new model of the evolution of eusociality with novel conclusions that appeared to overturn some major results from inclusive fitness. Here we report an expanded examination of this kind of model for the evolution of eusociality and show that all three of its apparently novel conclusions are essentially false. Contrary to their claims, genetic relatedness is important and causal, workers are agents that can evolve to be in conflict with the queen, and eusociality is not so difficult to evolve. The misleading conclusions all resulted not from incorrect math but from overgeneralizing from narrow assumptions or parameter values. For example, all of their models implicitly assumed high relatedness, but modifying the model to allow lower relatedness shows that relatedness is essential and causal in the evolution of eusociality. Their modeling strategy, properly applied, actually confirms major insights of inclusive fitness studies of kin selection. This broad agreement of different models shows that social evolution theory, rather than being in turmoil, is supported by multiple theoretical approaches. It also suggests that extensive prior work using inclusive fitness, from microbial interactions to human evolution, should be considered robust unless shown otherwise. Mathematical modelling shows that the evolution of sterile castes requires genetic relatedness but also involves conflicts between kin; these results contradict recent claims but agree with inclusive fitness theory. The evolution of sterile worker castes in social insects has fascinated biologists ever since Darwin; how can selection favor a trait that decreases reproductive fitness? W. D. Hamilton solved this dilemma in the 1960s with a theory showing that reproductive altruism could evolve if it increased the worker’s inclusive fitness, which included effects that it had on increasing the fitness of its relatives. This solution to a crucial evolutionary problem, sometimes called kin selection, was challenged in a recent paper. The paper generated much controversy, but no one has contested its new theoretical model of the evolution of eusociality, which appeared to overturn much of what was previously thought to be true from kin selection theory. Here we examine this model in greater depth, showing that its apparently novel conclusions are overgeneralized from narrow and often inappropriate assumptions. Instead, this modeling strategy yields results that confirm important insights from kin selection and inclusive fitness, such as the importance of relatedness and the existence of conflicts in social insect colonies.
Collapse
Affiliation(s)
- Xiaoyun Liao
- Department of Ecology and Evolutionary Biology, Rice University, Houston, Texas, United States of America
| | - Stephen Rong
- Biology Department, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - David C. Queller
- Biology Department, Washington University in St. Louis, St. Louis, Missouri, United States of America
- * E-mail:
| |
Collapse
|
50
|
|