1
|
Toxopeus J, Dowle EJ, Andaloori L, Ragland GJ. Variation in Thermal Sensitivity of Diapause Development among Individuals and over Time Predicts Life History Timing in a Univoltine Insect. Am Nat 2024; 203:E200-E217. [PMID: 38781522 DOI: 10.1086/729515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
AbstractPhysiological time is important for understanding the development and seasonal timing of ectothermic animals but has largely been applied to developmental processes that occur during spring and summer, such as morphogenesis. There is a substantial knowledge gap in the relationship between temperature and development during winter, a season that is increasingly impacted by climate change. Most temperate insects overwinter in diapause, a developmental process with little obvious morphological change. We used principles from the physiological time literature to measure and model the thermal sensitivity of diapause development rate in the apple maggot fly Rhagoletis pomonella, a univoltine fly whose diapause duration varies substantially within and among populations. We show that diapause duration can be predicted by modeling a relationship between temperature and development rate that is shifted toward lower temperatures compared with typical models of morphogenic, nondiapause development. However, incorporating interindividual variation and ontogenetic variation in the temperature-to-development rate relationship was critical for accurately predicting fly emergence, as diapause development proceeded more quickly at high temperatures later in diapause. We conclude that the conceptual framework may be flexibly applied to other insects and discuss possible mechanisms of diapause timers and implications for phenology with warming winters.
Collapse
|
2
|
Schebeck M, Lehmann P, Laparie M, Bentz BJ, Ragland GJ, Battisti A, Hahn DA. Seasonality of forest insects: why diapause matters. Trends Ecol Evol 2024:S0169-5347(24)00110-1. [PMID: 38777634 DOI: 10.1016/j.tree.2024.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 04/27/2024] [Accepted: 04/29/2024] [Indexed: 05/25/2024]
Abstract
Insects have major impacts on forest ecosystems, from herbivory and soil-nutrient cycling to killing trees at a large scale. Forest insects from temperate, tropical, and subtropical regions have evolved strategies to respond to seasonality; for example, by entering diapause, to mitigate adversity and to synchronize lifecycles with favorable periods. Here, we show that distinct functional groups of forest insects; that is, canopy dwellers, trunk-associated species, and soil/litter-inhabiting insects, express a variety of diapause strategies, but do not show systematic differences in diapause strategy depending on functional group. Due to the overall similarities in diapause strategies, we can better estimate the impacts of anthropogenic change on forest insect populations and, consequently, on key ecosystems.
Collapse
Affiliation(s)
- Martin Schebeck
- Institute of Forest Entomology, Forest Pathology and Forest Protection, Department of Forest and Soil Sciences, BOKU University, A-1190 Vienna, Austria.
| | - Philipp Lehmann
- Department of Animal Physiology, Zoological Institute and Museum, University of Greifswald, D-17489 Greifswald, Germany; Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden; Bolin Centre for Climate Research, SE-10691 Stockholm, Sweden
| | | | - Barbara J Bentz
- US Department of Agriculture, Forest Service, Rocky Mountain Research Station, Logan, UT 84321, USA
| | - Gregory J Ragland
- Department of Integrative Biology, University of Colorado-Denver, Denver, CO 80204, USA
| | - Andrea Battisti
- Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, I-35020 Legnaro, Italy
| | - Daniel A Hahn
- Department of Entomology and Nematology, University of Florida, Gainesville, FL 32611-0620, USA
| |
Collapse
|
3
|
Süess P, Roberts KT, Lehmann P. Temperature dependence of gas exchange patterns shift as diapause progresses in the butterfly Pieris napi. JOURNAL OF INSECT PHYSIOLOGY 2023; 151:104585. [PMID: 37977342 DOI: 10.1016/j.jinsphys.2023.104585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 11/03/2023] [Accepted: 11/12/2023] [Indexed: 11/19/2023]
Abstract
Insects have the capacity to significantly modify their metabolic rate according to environmental conditions and physiological requirement. Consequently, the respiratory patterns can range from continuous gas exchange (CGE) to discontinuous gas exchange (DGE). In the latter, spiracles are kept closed during much of the time, and gas exchange occurs only during short periods when spiracles are opened. While ultimate causes and benefits of DGE remain debated, it is often seen during insect diapause, a deep resting stage that insects induce to survive unfavourable environmental conditions, such as winter. The present study explores the shifts between CGE and DGE during diapause by performing long continuous respirometry measurements at multiple temperatures during key diapause stages in the green-veined white butterfly Pieris napi. The primary goal is to explore respiratory pattern as a non-invasive method to assess whether pupae are in diapause or have transitioned to post-diapause. Respiratory pattern can also provide insight into endogenous processes taking place during diapause, and the prolonged duration of diapause allows for the detailed study of the thermal dependence of the DGE pattern. Pupae change from CGE to DGE a few days after pupation, and this shift coincides with metabolic rate suppression during diapause initiation. Once in diapause, pupae maintain DGE even at elevated temperatures that significantly increase CO2 production. Instead of shifting respiratory pattern to CGE, pupae increase the frequency of DGE cycles. Since total CO2 released during a single open phase remains unchanged, our results suggest that P. napi pupae defend a maximum internal ρCO2 set point, even in their heavily suppressed diapause state. During post-diapause development, CO2 production increases as a function of development and changes to CGE during temperature conditions permissive for development. Taken together, the results show that respiratory patterns are highly regulated during diapause in P. napi and change predictably as diapause progresses.
Collapse
Affiliation(s)
- Philip Süess
- Department of Zoology, Stockholm University, 11418 Stockholm, Sweden.
| | - Kevin T Roberts
- Department of Zoology, Stockholm University, 11418 Stockholm, Sweden
| | - Philipp Lehmann
- Department of Zoology, Stockholm University, 11418 Stockholm, Sweden; Zoological Institute and Museum, University of Greifswald, 17489 Greifswald, Germany
| |
Collapse
|
4
|
Lackey ACR, Murray AC, Mirza NA, Powell THQ. The role of sexual isolation during rapid ecological divergence: Evidence for a new dimension of isolation in Rhagoletis pomonella. J Evol Biol 2023. [PMID: 37173822 DOI: 10.1111/jeb.14179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 03/05/2023] [Accepted: 03/23/2023] [Indexed: 05/15/2023]
Abstract
The pace of divergence and likelihood of speciation often depends on how and when different types of reproductive barriers evolve. Questions remain about how reproductive isolation evolves after initial divergence. We tested for the presence of sexual isolation (reduced mating between populations due to divergent mating preferences and traits) in Rhagoletis pomonella flies, a model system for incipient ecological speciation. We measured the strength of sexual isolation between two very recently diverged (~170 generations) sympatric populations, adapted to different host fruits (hawthorn and apple). We found that flies from both populations were more likely to mate within than between populations. Thus, sexual isolation may play an important role in reducing gene flow allowed by early-acting ecological barriers. We also tested how warmer temperatures predicted under climate change could alter sexual isolation and found that sexual isolation was markedly asymmetric under warmer temperatures - apple males and hawthorn females mated randomly while apple females and hawthorn males mated more within populations than between. Our findings provide a window into the early speciation process and the role of sexual isolation after initial ecological divergence, in addition to examining how environmental conditions could shape the likelihood of further divergence.
Collapse
Affiliation(s)
- Alycia C R Lackey
- University of Louisville, Louisville, Kentucky, USA
- Binghamton University, Binghamton, New York, USA
| | | | | | | |
Collapse
|
5
|
McIntyre T, Andaloori L, Hood GR, Feder JL, Hahn DA, Ragland GJ, Toxopeus J. Cold tolerance and diapause within and across trophic levels: Endoparasitic wasps and their fly host have similar phenotypes. JOURNAL OF INSECT PHYSIOLOGY 2023; 146:104501. [PMID: 36921838 DOI: 10.1016/j.jinsphys.2023.104501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/05/2023] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
Low temperatures associated with winter can limit the survival of organisms, especially ectotherms whose body temperature is similar to their environment. However, there is a gap in understanding how overwintering may vary among groups of species that interact closely, such as multiple parasitoid species that attack the same host insect. Here, we investigate cold tolerance and diapause phenotypes in three endoparasitoid wasps of the apple maggot fly Rhagoletis pomonella (Diptera: Tephritidae): Utetes canaliculatus, Diachasma alloeum, and Diachasmimorpha mellea (Hymenoptera: Braconidae). Using a combination of respirometry and eclosion tracking, we found that all three wasp species exhibited the same three diapause duration phenotypes as the fly host. Weak (short duration) diapause was rare, with <5 % of all three wasp species prematurely terminating diapause at 21 °C. Most D.mellea (93 %) entered a more intense (longer duration) diapause that did not terminate within 100 d at this warm temperature. The majority of U.canaliculatus (92 %) and D. alloeum (72 %) averted diapause (non-diapause) at 21 °C. There was limited interspecific variation in acute cold tolerance among the three wasp species: wasps and flies had similarly high survival (>87 %) following exposure to extreme low temperatures (-20 °C) as long as their body fluids did not freeze. The three wasp species also displayed little interspecific variation in survival following prolonged exposure to mild chilling of 8 or more weeks at 4 °C. Our study thus documents a remarkable conservation of cold tolerance and diapause phenotypes within and across trophic levels.
Collapse
Affiliation(s)
- Trinity McIntyre
- Department of Biology, St. Francis Xavier University, 2321 Notre Dame Ave, Antigonish NS B2G 2W5, Canada
| | - Lalitya Andaloori
- Department of Integrative Biology, University of Colorado Denver, 1151 Arapahoe St., Denver CO 80204, USA
| | - Glen R Hood
- Department of Biological Sciences, Wayne State University, 4841 Cass Avenue, Detroit MI 48201, USA
| | - Jeffrey L Feder
- Department of Biological Sciences, University of Notre Dame, Galvin Life Sciences Center, Notre Dame IN 46556, USA
| | - Daniel A Hahn
- Entomology and Nematology Department, University of Florida, 1881 Natural Area Drive, Gainesville FL 32611, USA
| | - Gregory J Ragland
- Department of Integrative Biology, University of Colorado Denver, 1151 Arapahoe St., Denver CO 80204, USA
| | - Jantina Toxopeus
- Department of Biology, St. Francis Xavier University, 2321 Notre Dame Ave, Antigonish NS B2G 2W5, Canada.
| |
Collapse
|
6
|
Kharva H, Feder JL, Hahn DA, Olsson SB. Rapid brain development and reduced neuromodulator titres correlate with host shifts in Rhagoletis pomonella. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220962. [PMID: 36117862 PMCID: PMC9449811 DOI: 10.1098/rsos.220962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 08/16/2022] [Indexed: 05/27/2023]
Abstract
Host shifts are considered a key generator of insect biodiversity. For insects, adaptation to new host plants often requires changes in larval/pupal development and adult behavioural preference toward new hosts. Neurochemicals play key roles in both development and behaviour and therefore provide a potential source for such synchronization. Here, we correlated life-history timing, brain development and corresponding levels of 14 neurochemicals in Rhagoletis pomonella (Diptera: Tephritidae), a species undergoing ecological speciation through an ongoing host shift from hawthorn to apple fruit. These races exhibit differences in pupal diapause timing as well as adult behavioural preference with respect to their hosts. This difference in behavioural preference is coupled with differences in neurophysiological response to host volatiles. We found that apple race pupae exhibited adult brain morphogenesis three weeks faster after an identical simulated winter than the hawthorn race, which correlated with significantly lower titres of several neurochemicals. In some cases, particularly biogenic amines, differences in titres were reflected in the mature adult stage, when host preference is exhibited. In summary, life-history timing, neurochemical titre and brain development can be coupled in this speciating system, providing new hypotheses for the origins of new species through host shifts.
Collapse
Affiliation(s)
- Hinal Kharva
- Naturalist-Inspired Chemical Ecology lab, National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bellary Road, Bangalore 560065, India
- School of Life Sciences, The University of Trans-Disciplinary Health Sciences and Technology, 74/2, Jarakabande Kaval, Post Attur via Yelahanka, Bangalore 560064, India
| | - Jeffrey L. Feder
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Daniel A. Hahn
- Department of Entomology and Nematology, University of Florida, Gainesville, FL 32611, USA
| | - Shannon B. Olsson
- Naturalist-Inspired Chemical Ecology lab, National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bellary Road, Bangalore 560065, India
| |
Collapse
|
7
|
Santoro C, O'Toole A, Finsel P, Alvi A, Musselman LP. Reducing ether lipids improves Drosophila overnutrition-associated pathophysiology phenotypes via a switch from lipid storage to beta-oxidation. Sci Rep 2022; 12:13021. [PMID: 35906462 PMCID: PMC9338069 DOI: 10.1038/s41598-022-16870-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 07/18/2022] [Indexed: 12/04/2022] Open
Abstract
High-calorie diets increase the risk of developing obesity, cardiovascular disease, type-two diabetes (T2D), and other comorbidities. These "overnutrition" diets also promote the accumulation of a variety of harmful lipids in the heart and other peripheral organs, known as lipotoxicity. However, the mechanisms underlying lipotoxicity and its influence on pathophysiology remain unknown. Our study uses genetics to identify the role of ether lipids, a class of potential lipotoxins, in a Drosophila model of overnutrition. A high-sugar diet (HSD) increases ether lipids and produces T2D-like pathophysiology phenotypes, including obesity, insulin resistance, and cardiac failure. Therefore, we targeted ether lipid biosynthesis through the enzyme dihydroxyacetonephosphate acyltransferase (encoded by the gene DHAPAT). We found that reducing DHAPAT in the fat body improved TAG and glucose homeostasis, cardiac function, respiration, and insulin signaling in flies fed a HSD. The reduction of DHAPAT may cause a switch in molecular signaling from lipogenesis to fatty acid oxidation via activation of a PPARα-like receptor, as bezafibrate produced similar improvements in HS-fed flies. Taken together, our findings suggest that ether lipids may be lipotoxins that reduce fitness during overnutrition.
Collapse
Affiliation(s)
- Christie Santoro
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Ashley O'Toole
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Pilar Finsel
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Arsalan Alvi
- Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | | |
Collapse
|
8
|
Calvert MB, Doellman MM, Feder JL, Hood GR, Meyers P, Egan SP, Powell THQ, Glover MM, Tait C, Schuler H, Berlocher SH, Smith JJ, Nosil P, Hahn DA, Ragland GJ. Genomically correlated trait combinations and antagonistic selection contributing to counterintuitive genetic patterns of adaptive diapause divergence in Rhagoletis flies. J Evol Biol 2021; 35:146-163. [PMID: 34670006 DOI: 10.1111/jeb.13952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 10/08/2021] [Accepted: 10/15/2021] [Indexed: 11/27/2022]
Abstract
Adaptation to novel environments can result in unanticipated genomic responses to selection. Here, we illustrate how multifarious, correlational selection helps explain a counterintuitive pattern of genetic divergence between the recently derived apple- and ancestral hawthorn-infesting host races of Rhagoletis pomonella (Diptera: Tephritidae). The apple host race terminates diapause and emerges as adults earlier in the season than the hawthorn host race, to coincide with the earlier fruiting phenology of their apple hosts. However, alleles at many loci associated with later emergence paradoxically occur at higher frequencies in sympatric populations of the apple compared to the hawthorn race. We present genomic evidence that historical selection over geographically varying environmental gradients across North America generated genetic correlations between two life history traits, diapause intensity and diapause termination, in the hawthorn host race. Moreover, the loci associated with these life history traits are concentrated in genomic regions in high linkage disequilibrium (LD). These genetic correlations are antagonistic to contemporary selection on local apple host race populations that favours increased initial diapause depth and earlier, not later, diapause termination. Thus, the paradox of apple flies appears due, in part, to pleiotropy or linkage of alleles associated with later adult emergence and increased initial diapause intensity, the latter trait strongly selected for by the earlier phenology of apples. Our results demonstrate how understanding of multivariate trait combinations and the correlative nature of selective forces acting on them can improve predictions concerning adaptive evolution and help explain seemingly counterintuitive patterns of genetic diversity in nature.
Collapse
Affiliation(s)
- McCall B Calvert
- Department of Integrative Biology, University of Colorado Denver, Denver, Colorado, USA
| | - Meredith M Doellman
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Jeffrey L Feder
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.,Environmental Change Initiative, University of Notre Dame, Notre Dame, Indiana, USA.,Advanced Diagnostics and Therapeutics Initiative, University of Notre Dame, Notre Dame, Indiana, USA
| | - Glen R Hood
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.,Department of Biosciences, Rice University, Houston, Texas, USA.,Department of Biological Sciences, Wayne State University, Detroit, Michigan, USA
| | - Peter Meyers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Scott P Egan
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.,Environmental Change Initiative, University of Notre Dame, Notre Dame, Indiana, USA.,Advanced Diagnostics and Therapeutics Initiative, University of Notre Dame, Notre Dame, Indiana, USA.,Department of Biosciences, Rice University, Houston, Texas, USA
| | - Thomas H Q Powell
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.,Department of Biological Sciences, Binghamton University (State University of New York), Binghamton, New York, USA
| | - Mary M Glover
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Cheyenne Tait
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA
| | - Hannes Schuler
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.,Faculty of Science and Technology, Free University of Bozen-Bolzano, Bozen, Italy
| | - Stewart H Berlocher
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - James J Smith
- Department of Entomology, Lyman Briggs College, Michigan State University, East Lansing, Michigan, USA
| | - Patrik Nosil
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK.,CEFE, CNRS, EPHE, IRD, Univ Montpellier, Univ Paul Valéry Montpellier 3, Montpellier, France
| | - Daniel A Hahn
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | - Gregory J Ragland
- Department of Integrative Biology, University of Colorado Denver, Denver, Colorado, USA.,Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana, USA.,Advanced Diagnostics and Therapeutics Initiative, University of Notre Dame, Notre Dame, Indiana, USA
| |
Collapse
|
9
|
Unbehend M, Kozak GM, Koutroumpa F, Coates BS, Dekker T, Groot AT, Heckel DG, Dopman EB. bric à brac controls sex pheromone choice by male European corn borer moths. Nat Commun 2021; 12:2818. [PMID: 33990556 PMCID: PMC8121916 DOI: 10.1038/s41467-021-23026-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 03/28/2021] [Indexed: 02/03/2023] Open
Abstract
The sex pheromone system of ~160,000 moth species acts as a powerful form of assortative mating whereby females attract conspecific males with a species-specific blend of volatile compounds. Understanding how female pheromone production and male preference coevolve to produce this diversity requires knowledge of the genes underlying change in both traits. In the European corn borer moth, pheromone blend variation is controlled by two alleles of an autosomal fatty-acyl reductase gene expressed in the female pheromone gland (pgFAR). Here we show that asymmetric male preference is controlled by cis-acting variation in a sex-linked transcription factor expressed in the developing male antenna, bric à brac (bab). A genome-wide association study of preference using pheromone-trapped males implicates variation in the 293 kb bab intron 1, rather than the coding sequence. Linkage disequilibrium between bab intron 1 and pgFAR further validates bab as the preference locus, and demonstrates that the two genes interact to contribute to assortative mating. Thus, lack of physical linkage is not a constraint for coevolutionary divergence of female pheromone production and male behavioral response genes, in contrast to what is often predicted by evolutionary theory.
Collapse
Affiliation(s)
- Melanie Unbehend
- Department of Entomology, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Genevieve M Kozak
- Department of Biology, Tufts University, Medford, MA, USA
- Department of Biology, University of Massachusetts Dartmouth, Dartmouth, MA, USA
| | - Fotini Koutroumpa
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, XH, the Netherlands
- INRAE, Sorbonne Université, CNRS, IRD, UPEC, Université Paris Diderot, Institute of Ecology and Environmental Sciences of Paris, Versailles, Cedex, France
| | - Brad S Coates
- USDA-ARS, Corn Insects and Crop Genetics Research Unit, Ames, IA, USA
| | - Teun Dekker
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Astrid T Groot
- Department of Entomology, Max Planck Institute for Chemical Ecology, Jena, Germany
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, XH, the Netherlands
| | - David G Heckel
- Department of Entomology, Max Planck Institute for Chemical Ecology, Jena, Germany.
| | - Erik B Dopman
- Department of Biology, Tufts University, Medford, MA, USA.
| |
Collapse
|
10
|
Inskeep KA, Doellman MM, Powell THQ, Berlocher SH, Seifert NR, Hood GR, Ragland GJ, Meyers PJ, Feder JL. Divergent diapause life history timing drives both allochronic speciation and reticulate hybridization in an adaptive radiation of Rhagoletis flies. Mol Ecol 2021; 31:4031-4049. [PMID: 33786930 DOI: 10.1111/mec.15908] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 03/01/2021] [Accepted: 03/15/2021] [Indexed: 12/18/2022]
Abstract
Divergent adaptation to new ecological opportunities can be an important factor initiating speciation. However, as niches are filled during adaptive radiations, trait divergence driving reproductive isolation between sister taxa may also result in trait convergence with more distantly related taxa, increasing the potential for reticulated gene flow across the radiation. Here, we demonstrate such a scenario in a recent adaptive radiation of Rhagoletis fruit flies, specialized on different host plants. Throughout this radiation, shifts to novel hosts are associated with changes in diapause life history timing, which act as "magic traits" generating allochronic reproductive isolation and facilitating speciation-with-gene-flow. Evidence from laboratory rearing experiments measuring adult emergence timing and genome-wide DNA-sequencing surveys supported allochronic speciation between summer-fruiting Vaccinium spp.-infesting Rhagoletis mendax and its hypothesized and undescribed sister taxon infesting autumn-fruiting sparkleberries. The sparkleberry fly and R. mendax were shown to be genetically discrete sister taxa, exhibiting no detectable gene flow and allochronically isolated by a 2-month average difference in emergence time corresponding to host availability. At sympatric sites across the southern USA, the later fruiting phenology of sparkleberries overlaps with that of flowering dogwood, the host of another more distantly related and undescribed Rhagoletis taxon. Laboratory emergence data confirmed broadly overlapping life history timing and genomic evidence supported on-going gene flow between sparkleberry and flowering dogwood flies. Thus, divergent phenological adaptation can drive the initiation of reproductive isolation, while also enhancing genetic exchange across broader adaptive radiations, potentially serving as a source of novel genotypic variation and accentuating further diversification.
Collapse
Affiliation(s)
- Katherine A Inskeep
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Meredith M Doellman
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Thomas H Q Powell
- Department of Biological Sciences, Binghamton University (State University of New York), Binghamton, NY, USA
| | - Stewart H Berlocher
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Nicholas R Seifert
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Glen R Hood
- Department of Biological Sciences, Wayne State University, Detroit, MI, USA
| | - Gregory J Ragland
- Department of Integrative Biology, University of Colorado Denver, Denver, CO, USA
| | - Peter J Meyers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Jeffrey L Feder
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| |
Collapse
|
11
|
Li Q, Lin X, Li J, Liu B, Huang X. Differentiation in the eastern Asian Periphyllus koelreuteriae (Hemiptera: Aphididae) species complex driven by climate and host plant. Biol J Linn Soc Lond 2021. [DOI: 10.1093/biolinnean/blaa206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Divergent adaptation to different ecological conditions is regarded as important for speciation. For phytophagous insects, there is limited empirical evidence on species differentiation driven by climate and host plant. The recent application of molecular data and integrative taxonomic practice may improve our understanding of population divergence and speciation. Periphyllus koelreuteriae aphids feed exclusively on Koelreuteria (Sapindaceae) in temperate and subtropical regions of eastern Asia, and show morphological and phenological variations in different regions. In this study, phylogenetic and haplotype network analyses based on four genes revealed that P. koelreuteriae populations comprised three distinct genetic clades corresponding to climate and host plants, with the populations from subtropical highland regions and on Koelreuteria bipinnata host plants representing the most basal clade. These genetic lineages also showed distinct characteristics in terms of morphology and life cycle. The results indicate that P. koelreuteriae is a species complex with previously unrevealed lineages, whose differentiation may have been driven by climatic difference and host plant.
Collapse
Affiliation(s)
- Qiang Li
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaolan Lin
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Junjie Li
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Bing Liu
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Xiaolei Huang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou, China
| |
Collapse
|
12
|
Toxopeus J, Gadey L, Andaloori L, Sanaei M, Ragland GJ. Costs of averting or prematurely terminating diapause associated with slow decline of metabolic rates at low temperature. Comp Biochem Physiol A Mol Integr Physiol 2021; 255:110920. [PMID: 33582264 DOI: 10.1016/j.cbpa.2021.110920] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 01/25/2021] [Accepted: 02/08/2021] [Indexed: 12/28/2022]
Abstract
Diapause, a form of insect dormancy, generally facilitates overwintering by increasing cold tolerance and decreasing energy drain at high temperatures via metabolic rate suppression. Averting or terminating diapause prior to winter is generally assumed to be a lethal phenotype. However, low temperature acclimation can also increase cold tolerance and decrease metabolic rates. Here, we tested the hypothesis that non- and post-diapause individuals in a cold-induced quiescence can achieve a diapause-like phenotype, compensating for the potential costs of averting diapause. We tested this in the apple maggot fly Rhagoletis pomonella, which typically overwinters in the soil as a diapause pupa, but can avert diapause (non-diapause) or terminate diapause early ('weak diapause') when reared at warm temperatures. Metabolic rates were initially higher in non- and post-diapause than diapause pupae at high (25 °C) and low (4 °C) temperatures, but quiescent non- and post-diapause pupae achieved diapause-like metabolic rates slowly over time when incubated at 4 °C for several weeks. We found that diapause and quiescent pupae were freeze-avoidant and had similar tolerance of extreme low temperatures (cooling to c. -18 °C) following 8 weeks acclimation at 4 °C. Despite high tolerance of subzero temperatures, quiescent pupae did not survive well when chilled for prolonged periods (8 weeks or more) at 4 °C. We conclude that cold acclimation can only partially compensate for costs associated with aversion or premature termination of diapause, and that energy drain at low (not just high) temperatures likely contributes to chilling mortality in quiescent insects.
Collapse
Affiliation(s)
- Jantina Toxopeus
- Department of Integrative Biology, University of Colorado, Denver, 1151 Arapahoe St, Denver, CO, 80204, United States.
| | - Lahari Gadey
- Department of Integrative Biology, University of Colorado, Denver, 1151 Arapahoe St, Denver, CO, 80204, United States.
| | - Lalitya Andaloori
- Department of Integrative Biology, University of Colorado, Denver, 1151 Arapahoe St, Denver, CO, 80204, United States.
| | - Matin Sanaei
- Department of Integrative Biology, University of Colorado, Denver, 1151 Arapahoe St, Denver, CO, 80204, United States.
| | - Gregory J Ragland
- Department of Integrative Biology, University of Colorado, Denver, 1151 Arapahoe St, Denver, CO, 80204, United States.
| |
Collapse
|
13
|
Wilsterman K, Ballinger MA, Williams CM. A unifying, eco‐physiological framework for animal dormancy. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13718] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kathryn Wilsterman
- Biological Sciences University of Montana Missoula MT USA
- Integrative Biology University of California Berkeley CA USA
| | | | | |
Collapse
|
14
|
Dowle EJ, Powell THQ, Doellman MM, Meyers PJ, Calvert MB, Walden KKO, Robertson HM, Berlocher SH, Feder JL, Hahn DA, Ragland GJ. Genome-wide variation and transcriptional changes in diverse developmental processes underlie the rapid evolution of seasonal adaptation. Proc Natl Acad Sci U S A 2020; 117:23960-23969. [PMID: 32900926 PMCID: PMC7519392 DOI: 10.1073/pnas.2002357117] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Many organisms enter a dormant state in their life cycle to deal with predictable changes in environments over the course of a year. The timing of dormancy is therefore a key seasonal adaptation, and it evolves rapidly with changing environments. We tested the hypothesis that differences in the timing of seasonal activity are driven by differences in the rate of development during diapause in Rhagoletis pomonella, a fly specialized to feed on fruits of seasonally limited host plants. Transcriptomes from the central nervous system across a time series during diapause show consistent and progressive changes in transcripts participating in diverse developmental processes, despite a lack of gross morphological change. Moreover, population genomic analyses suggested that many genes of small effect enriched in developmental functional categories underlie variation in dormancy timing and overlap with gene sets associated with development rate in Drosophila melanogaster Our transcriptional data also suggested that a recent evolutionary shift from a seasonally late to a seasonally early host plant drove more rapid development during diapause in the early fly population. Moreover, genetic variants that diverged during the evolutionary shift were also enriched in putative cis regulatory regions of genes differentially expressed during diapause development. Overall, our data suggest polygenic variation in the rate of developmental progression during diapause contributes to the evolution of seasonality in R. pomonella We further discuss patterns that suggest hourglass-like developmental divergence early and late in diapause development and an important role for hub genes in the evolution of transcriptional divergence.
Collapse
Affiliation(s)
- Edwina J Dowle
- Department of Integrative Biology, University of Colorado Denver, Denver, CO 80217;
- Department of Anatomy, University of Otago, 9016 Dunedin, New Zealand
| | - Thomas H Q Powell
- Department of Biological Sciences, Binghamton University-State University of New York, Binghamton, NY 13902
- Department of Entomology and Nematology, University of Florida, Gainesville, FL 32611
| | - Meredith M Doellman
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556
- Department of Ecology and Evolution, The University of Chicago, Chicago, IL 60637
| | - Peter J Meyers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556
| | - McCall B Calvert
- Department of Integrative Biology, University of Colorado Denver, Denver, CO 80217
| | - Kimberly K O Walden
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Hugh M Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Stewart H Berlocher
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Jeffrey L Feder
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556
- Environmental Change Initiative, University of Notre Dame, Notre Dame, IN 46556
| | - Daniel A Hahn
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Gregory J Ragland
- Department of Integrative Biology, University of Colorado Denver, Denver, CO 80217;
- Department of Entomology, Kansas State University, Manhattan, KS 66506
| |
Collapse
|
15
|
Meyers PJ, Doellman MM, Ragland GJ, Hood GR, Egan SP, Powell THQ, Nosil P, Feder JL. Can the genomics of ecological speciation be predicted across the divergence continuum from host races to species? A case study in Rhagoletis. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190534. [PMID: 32654640 DOI: 10.1098/rstb.2019.0534] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Studies assessing the predictability of evolution typically focus on short-term adaptation within populations or the repeatability of change among lineages. A missing consideration in speciation research is to determine whether natural selection predictably transforms standing genetic variation within populations into differences between species. Here, we test whether and how host-related selection on diapause timing associates with genome-wide differentiation during ecological speciation by comparing ancestral hawthorn and newly formed apple-infesting host races of Rhagoletis pomonella to their sibling species Rhagoletis mendax that attacks blueberries. The associations of 57 857 single nucleotide polymorphisms in a diapause genome-wide-association study (GWAS) on the hawthorn race strongly predicted the direction and magnitude of genomic divergence among the three fly populations at a field site in Fennville, MI, USA. The apple race and R. mendax show parallel changes in the frequencies of putative inversions on three chromosomes associated with the earlier fruiting times of apples and blueberries compared to hawthorns. A diapause GWAS on R. mendax revealed compensatory changes throughout the genome accounting for the earlier eclosion of blueberry, but not apple flies. Thus, a degree of predictability, although not complete, exists in the genomics of diapause across the ecological speciation continuum in Rhagoletis. The generality of this result is placed in the context of other similar systems. This article is part of the theme issue 'Towards the completion of speciation: the evolution of reproductive isolation beyond the first barriers'.
Collapse
Affiliation(s)
- Peter J Meyers
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Meredith M Doellman
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Gregory J Ragland
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Environmental Change Initiative, University of Notre Dame, Notre Dame, IN 46556, USA.,Department of Integrative Biology, University of Colorado Denver, Denver, CO 80217, USA
| | - Glen R Hood
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - Scott P Egan
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Department of Biosciences, Rice University, Houston, TX 77005, USA.,Advanced Diagnostics and Therapeutics Initiative, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Thomas H Q Powell
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Department Biological Sciences, Binghamton University, Binghamton, NY 13902, USA
| | - Patrik Nosil
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.,Centre d'Ecologie Fonctionnelle and Evolutive, Centre National de la Recherche Scientifique, Montpellier 34293, France
| | - Jeffrey L Feder
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Environmental Change Initiative, University of Notre Dame, Notre Dame, IN 46556, USA.,Advanced Diagnostics and Therapeutics Initiative, University of Notre Dame, Notre Dame, IN 46556, USA
| |
Collapse
|