Disruption of an ant-plant mutualism shapes interactions between lions and their primary prey

A call for increased integration of experimental approaches in movement ecology

Rapid developments in animal-tracking technology have enabled major advances in the field of movement ecology, which seeks to understand the drivers and consequences of movement across scales, taxa, and ecosystems. The field has made ground-breaking discoveries, yet the majority of studies in movement ecology remain reliant on observational approaches. While important, observational studies are limited compared to experimental methods that can reveal causal relationships and underlying mechanisms. As such, we advocate for a renewed focus on experimental approaches in animal movement ecology. We illustrate a way forward in experimental movement ecology across two fundamental levels of biological organisation: individuals and social groups. We then explore the application of experiments in movement ecology to study anthropogenic influences on wildlife movement, and enhance our mechanistic understanding of conservation interventions. In each of these examples, we draw upon previous research that has effectively employed experimental approaches, while highlighting outstanding questions that could be answered by further experimentation. We conclude by highlighting the ways experimental manipulations in both laboratory and natural settings provide a promising way forward to generate mechanistic understandings of the drivers, consequences, and conservation of animal movement.

Mutualisms as a framework for multi-robot collaboration

Biology has inspired robotics since its inception as an academic discipline. However, the use of ecological principles in robotics is still relatively rare and in this paper, we explore how such principles can not only be of relevance to robotics, but can reciprocally lead to new insights into ecology. In particular, we investigate how mutualisms-jointly beneficial interactions between members of different species-can inform collaborative architectures for multi-robot systems comprised of different types of robots. To better understand how mutualisms can have practical relevance in robotics, we present a case study where the landscape heterogeneity, i.e., the configuration of the landscape, is varied, and we measure the efficiency of robots functioning independently or involved in a mutualism. We show that landscape composition impacts the benefits of forming mutualisms, which, in turn, has implications for mutualism emergence and stability in ecology. Moreover, through this case study, the concept of fitness and its components can be introduced for engineered systems, leading to notions of longevity, task fecundity, and, ultimately, robot fitness.

The Eurasian Magpie Preys on the Nests of Vinous-throated Parrotbills in Invasive Smooth Cordgrass

Native animals worldwide are experiencing long-term coexistence with invasive plants, leading to diverse behavioral changes. Invasive plants may create new habitat structures that affect the distribution or behavior of prey, which in turn might attract predators to these novel habitats, thereby altering predator-prey dynamics within the ecosystem. However, this phenomenon is rarely reported. Our previous research found that in the Yellow Sea wetlands of China, the native bird species, the vinous-throated parrotbill (Sinosuthora webbiana), has adapted to breeding in the invasive smooth cordgrass (Spartina alterniflora) by increasing its nesting height. Here, our observations indicate that in cordgrass habitats, the main nest predator of parrotbills was the Eurasian magpie (Pica pica), accounting for 75% of predation events. In contrast, in native habitats, the primary predators were mammals and snakes, accounting for 83% of predation events, with no nests being predated by magpies. We believe that changes in the breeding and nesting behavior of parrotbills may have attracted magpie predation in cordgrass habitats. Our findings may provide an empirical case of how behavioral changes induced by invasive plants can lead to dynamic shifts in predation relationships. We advocate for further research into this intriguing phenomenon, as it could enhance our understanding of changes in interspecific relationships and their ecological consequences within the context of biological invasions.

Deconstructing inflammatory memory across tissue set points using cell circuit motifs

Tissue ecosystems are cellular communities that maintain set points through a network of intercellular interactions. We position health and chronic inflammatory disease as alternative stable set points that are (1) robust to perturbation and (2) capable of adaptation and memory. Inflammatory memory, which is the storage of prior experience to durably influence future responsiveness, is central to how tissue ecosystems may be pushed past tipping points that stabilize disease over health. Here, we develop a reductionist framework of circuit motifs that recur in tissue set points. In type 2 immunity, we distinctly find the emergence of 2-cell positive feedback motifs. In contrast, directional motif relays and 3-cell networks feature more prominently in type 1 and 17 responses. We propose that these differences guide the ecologic networks established after surpassing tipping points and associate closely with therapeutic responsiveness. We highlight opportunities to improve our current knowledge of how circuit motifs interact when building toward tissue-level networks across adaptation and memory. By developing new tools for circuit motif nomination and applying them to temporal profiling of tissue ecosystems, we hope to dissect the stability of the chronic inflammatory set point and open therapeutic avenues for rewriting memory to restore health.

Positive interactions and interdependence in communities

Facilitative interactions play crucial roles in community organization, and the stress gradient hypothesis (SGH) provides a simple conceptual framework for the context-dependency of competitive and facilitative interactions. The idea is that positive interactions are more common under high physical and consumer stress, where species benefit from stress-tolerant neighbors, than in benign environments. We explore insights from the SGH into ecological generality, niche theory, community assembly, and diversity effects on ecosystem function and discuss how the SGH can inform our understanding of rapid evolution, mutualisms, exotic invasions, and facilitation cascades. We suggest that, with escalating global stresses, the SGH may provide a conceptual template for an interdependent perspective in ecology that can contribute to conservation and restoration efforts.

Why Were Zebras Not Domesticated? A Review of Domesticability Traits and Tests of Their Role in Ungulate Domestications with Macroevolutionary Models

Since Darwin, many evolutionary and behavioral researchers have considered the role of phenotypic traits that favor the domestication of nonhuman animals. Among such proposed traits are a species' social structure, level of intra- and interspecific agonistic interactions, sociosexual behaviors, parental strategies, reaction to humans, habitat preference, dietary habits, developmental trajectories, and utility to humans. However, little to no comparative phylogenetic evidence exists concerning the importance of these attributes for the domestication of animals. Moreover, rather than considering domestication as a dichotomous event (non-domesticated vs. domesticated), humans and their potential domesticates encountered numerous socioecological challenges/obstacles during the domestication process before reaching the stage of full domestication. The present study explored the influence of adult body mass, gregariousness, dietary breadth, and reaction to humans on the domestication process of ungulates. The phylogenetic comparative model revealed that capture myopathy (CM), as a proxy for reaction to humans, negatively and significantly influenced the domestication process. The present paper also explored the evolution of CM in equine species in response to the presence of large carnivoran predators during the Pleistocene. Ecologies that preserved most of the large carnivoran predators of equine species also featured more equine taxa with CM (e.g., zebras), which were thus less suitable for domestication.

Rich specialized insect damage on Pliocene leaves from the Mahuadanr Valley (India) growing under a warm climate with weak seasonality

Plant-insect interactions play a crucial role in shaping terrestrial ecosystems, influencing abundance and distribution of plant species. In the present study, we investigated leaf-mining patterns on fossil leaves from Pliocene strata of the Mahuadanr Valley, Jharkhand, eastern India, deposited under a seasonal tropical climate, and reported complex interactions between plants and insects. We identified 11 distinct mining morphotypes. These morphotypes were mainly found on Dipterocarpaceae, Fabaceae, Lauraceae, and Moraceae; similar mining traces were also observed in the contemporary vegetation surrounding the fossil site. Although mining richness was relatively high, only 2.6% of all leaves in the fossil assemblage were mined. We compared mining richness and abundance values with previously reported values for galling. While richness was slightly lower for galling, almost 50% of all fossil leaves were galled. A literature survey on mining and galling patterns in modern vegetation suggests that there is no global explanation for richness of mining or gall-inducing insects. Thus, low nutrient availability in the ancient forest, dominance of semideciduous leaves with hard texture, and different habitats in the same forest ecosystem, such as well-drained forests and riparian stands, may all have favored different types of specialized plant-insect interactions.

Vulnerability of terrestrial vertebrate food webs to anthropogenic threats in Europe

Vertebrate species worldwide are currently facing significant declines in many populations. Although we have gained substantial knowledge about the direct threats that affect individual species, these threats only represent a fraction of the broader vertebrate threat profile, which is also shaped by species interactions. For example, threats faced by prey species can jeopardize the survival of their predators due to food resource scarcity. Yet, indirect threats arising from species interactions have received limited investigation thus far. In this study, we investigate the indirect consequences of anthropogenic threats on biodiversity in the context of European vertebrate food webs. We integrated data on trophic interactions among over 800 terrestrial vertebrates, along with their associated human-induced threats. We quantified and mapped the vulnerability of various components of the food web, including species, interactions, and trophic groups to six major threats: pollution, agricultural intensification, climate change, direct exploitation, urbanization, and invasive alien species and diseases. Direct exploitation and agricultural intensification were two major threats for terrestrial vertebrate food webs: affecting 34% and 31% of species, respectively, they threaten 85% and 69% of interactions in Europe. By integrating network ecology with threat impact assessments, our study contributes to a better understanding of the magnitude of anthropogenic impacts on biodiversity.

A big-headed problem drives an ecological chain reaction

Disruption of key species interactions reverberates across an African savanna.