Synopsis Disabled people are present in the biological sciences, yet efforts are ongoing to build truly welcoming and anti-ableist biology community spaces. We undertake this narrative review and call to action on disabled and neurodivergent perception, community, and identity in the biosciences to bring attention to the disabled biologist community and to highlight areas of support for disabled scientists. This work serves as an introductory paper for the special issue from the 2026 SICB symposium of the same name. The narrative literature review component uses search terms related to disability identity and biological sciences to explore the status of bioscience and biology education literature, with a focus on the last 25 years. We use a Critical Disability Theory framework to underscore disability as identity, and to further explore the social dynamics of disability inclusion or exclusion in STEM. We summarize the literature, its potential impact, and its recommendations for building more welcoming spaces for disabled people in biology. Our call to action synthesizes what has been recommended while providing further areas of work which can build disabled biology community and communities of care.
Migratory whales are excellent sentinels of the health of marine ecosystems as they traverse whole ocean basins. Their metabolic balance, body condition, and reproductive suppression during marine heatwaves reflect their sensitivity to ocean conditions. A pilot study used corticosteroids as biomarkers of metabolic stress responses. Routine validations were conducted for cortisol, corticosterone, and aldosterone enzyme immunoassays, with differing success for each sex. High-pressure liquid chromatography (HPLC) profiles for the same hormones were analyzed on extracted blubber for each sex. No immunoreactivity of female blubber corresponded to the corticosterone peak, while 60% total immunoreactivity in the males was corticosterone. Conversely, no immunoreactivity of male blubber corresponded to cortisol, whereas 41% total immunoreactivity in females was cortisol. Both females and males had immunoreactive peaks that overlapped with aldosterone. The disparity in glucocorticoids between sexes likely reflected differential metabolism of the hormones in blubber. In a follow-up study, reproductive and metabolic biomarkers were concurrently monitored and pregnancy was detected from elevated blubber progesterone concentrations in biopsies from adult female humpback whales from 2020 to 2024 with long-term sighting histories near Juneau, Alaska. Annual pregnancy rates were 0.36 to 0.75 and minimum calving rates were predictably lower (0.18-0.50). An annual realized population growth rate (1.001-1.059) was estimated using an age-structured Lotka model, where data from the literature were used for age-specific survival rates and average age of first birth, and year-specific data from this study to estimate reproductive rates. The difference between the pregnancy rate and the minimum calving rate in late spring to summer, post oceanic migration, indicated this is a key period when pregnancy may be disrupted and perinatal mortality may occur. Annual monitoring of unique subpopulations will improve knowledge of individual's physiological well-being, and assessing pregnancy, calving, and realized population growth rates aids our understanding of endocrine adaptations that influence population's stability during changing ocean conditions.
Sea angels (gymnosomatous pteropods) are small zooplanktonic shell-less marine snails inhabiting the meso- and epipelagic zones. They swim in an intermediate Reynolds number regime using highly flexible, wing-like parapodia in order to capture prey, avoid predators, and perform diel vertical migration. However, the kinematics and fluid dynamics of gymnosome swimming are not well understood, particularly for species residing in low-viscosity, subtropical waters. Here we use high-speed stereophotogrammetry and dual brightfield particle image velocimetry (PIV) systems to investigate the swimming of the rare subtropical species Pneumoderma atlantica, captured off the coast of Bermuda. In particular, we quantify wing kinematics for hovering and slow upwards swimming and compare our results with morphologically similar temperate and polar species, which can be up to twice as large and swim in water up to twice as viscous. Like tiny insects flying in a similar regime, the chordwise Reynolds number appears to be inversely related to the wing angle of attack and stroke plane. Thus both the small, warm-water and the large polar gymnosomes seem to use their wings more like paddles to generate upward forces while the temperate species seems to use its parapodia more like wings to generate lift. Further, we provide the first flow measurements of a swimming gymnosome, these at somewhat higher swimming speeds, which show that gymnosomes employ an unsteady flow interaction between the wings and body (similar to the clap-and-fling mechanism) twice during each stroke cycle which likely generates additional lift. These findings provide insight into how similar locomotion modes may be adapted to different viscosities and into the widespread use of lift-generating, clap-and-fling-like mechanisms among marine snails.
The collective motion of a fish school emerges from communication between its members, yet the sensory mechanisms mediating this communication remain largely unclear. While the visual system is essential for schooling in a diversity of species, the processing of visual stimuli is substantially slower than the mechanosensory lateral-line system. Through experimental manipulation, previous experiments found only modest contributions by the lateral line on time-averaged schooling kinematics, but substantial changes on the network structure of information sharing. To resolve this apparent discrepancy, we combined hydrodynamic modeling with kinematic and network analysis of schools of 60 rummy-nose tetra (Petitella bleheri). These fish exhibit intermittent motion that requires individuals to respond rapidly to their neighbors during periods of acceleration and deceleration to maintain a cohesive school. Through an analysis of the pairwise cross-correlation of speed during accelerations, we found that fish capable of sensing the flow of their neighbors responded with a latency that was one-third less than that of schools of fish with a compromised lateral line. In addition, flow-sensing schools exhibited higher mutual information (MI) and a more efficient and uniform communication network. No differences in response latency or MI were observed during periods of deceleration. These results demonstrate that the lateral line serves not as a redundant channel to vision, but as a fast sensory pathway that tightens temporal coupling between neighbors during the most rapid motion of fish schools.
Abstract Collective behavior is a ubiquitous phenomenon observed in a diverse array of species across scales, from single-celled microorganisms to large vertebrates like fish and birds. In aquatic and aerial environments, collective movements are inherently mechanical: as organisms move, they displace the surrounding medium, creating dynamic flow fields that provide opportunities for passive energy recycling and active fluid-mediated communication. We demonstrate how animals across scales assemble in fluid environments of different Reynolds number (Re) regimes. In addition, we highlight how emerging methodologies from artificial intelligence to biomimetic robotics enable new measurements of collective behavior in dynamic fluid environments. Finally, we propose a comparative framework that explores fluid-mediated collective behavior as a critical link between functional morphology and behavioral ecology.
Animal behavior is inherently multi-scale. Traditional neuroethology approaches have focused on the neural circuit level and free behavior level studies. In bridging the behavioral-neural divide, simultaneous neural recordings with behavioral readouts have been immensely successful in recent years. However, such studies often need vast resources and technological investment, often with fragile and expensive measurement tools. Therefore, there is a need for frugal-science-style devices for neuroethology. We define a class of such tools called "Exploratory Tools" using a six-point criteria. These are tools meant to be used in an exploratory manner in overcoming methodological challenges in technically complex and uncertain experiments. We outline their utility under the "Explore/Exploit framework," an approach involving the use of such specialized "Exploratory Tools" in combination with conventional, high-end devices. We advocate for the adoption of this type of framework into academic culture. As case-study for such tools, we performed "Behavioral Electrophysiology" on the hawkmoth Manduca sexta with simultaneous measurement of neural activity and flapping force. The force measurements were made with a novel, low-cost force transducer as a binary behavioral readout. This hybrid approach enabled an assessment of our experimental challenges, and allowed us to test critical innovations such as a wing-release mechanism and a new kind of syringe-hook apparatus.
The smallest insects are particularly useful for studying how body size affects flight mechanics, because they include the smallest flying animals and operate at single-digit Reynolds numbers, where viscous forces play a much greater role than in larger insects and other flying animals. This area has attracted researchers for several decades, but until recently all work on "miniature" insects focused on species that are many times larger than the smallest insects. Recent work on some of the smallest insects has revealed the uniqueness of both the structure of their wing apparatus and the kinematics and aerodynamics of their flight. This review summarizes recent advances in the study of miniature insect flight and identifies unresolved questions that will shape future research in biology, biomechanics, and bioinspired technologies, providing broad prospects for a comprehensive study of this subject.
Synopsis Unprecedented changes to the natural world necessitate high volumes of data to characterize environmental changes and understand the behavioral and physiological responses of animals in these changing environments. Recent technological advances in electronics, material science, cameras, and artificial intelligence offer multiple platforms to collect extremely detailed environmental and behavioral data. However, the broader adoption of these emerging technologies is limited by many factors. Open-source technologies can provide a path forward to unlocking the potential of these new technologies for conservation science. This special issue of Integrative and Comparative Biology aims to highlight current trends and the novel application of open-source tools. The papers in this issue demonstrate the diversity of emerging tools and how these tools can be applied to address many different research needs. Together, these studies illustrate the scope and breadth of tools available and elucidate how open-source approaches can increase the accessibility of these tools. As habitats, ecosystems, and environmental conditions continue to change, data collection is a priority so researchers and conservation practitioners can assess how species and communities are impacted. Through this special issue, a path towards an accessible modern data collection landscape is called for – increased institutional and governmental support to develop open-source platforms and increased collaborations among ecologists and engineers can help to produce more accessible, useful, affordable, and high-quality monitoring tools.
When honeybee colonies reproduce by fission, several thousand bees and their queen depart the parental nest and temporarily form a dense cluster on a tree branch or other surface while searching for a new nest site. Once the new nest site is selected, the swarm disassembles and flies toward it. How honeybees transition rapidly between dispersed flight and an aggregated cluster remains an open question. Here, we introduce an experimental framework for studying honeybee swarm assembly and disassembly. The approach combines a method for inducing swarm departure and reassembly with a three-dimensional imaging pipeline to track individual flying bees together with the evolving morphology of the swarm during formation and dissolution. We report results from a representative swarming event. During assembly, swarms rapidly form low-density clusters before undergoing a slower contraction to a more dense steady state configuration. In contrast, disassembly occurs significantly faster than assembly and is characterized by strongly divergent flight, with bees departing the swarm in all directions. Overall, this method is able to demonstrate the coupled flight and morphological dynamics that underlie honeybee swarm assembly. Because the system is relatively low-cost and low-power, it is readily adaptable for three-dimensional imaging of other biological collectives in naturalistic environments.
In biology, variation is the norm, not the exception. This particularly holds true for the concepts of sex and sex determination, which we refer to here as biology of sex. Unfortunately, biology of sex topics are often taught using oversimplified content, situating sex as a simple, genetically determined binary, and that mammals are the predominant model for biology of sex across organisms. Teaching using these oversimplifications leads students to develop a limited understanding of biology of sex topics, which limits their capacity as future researchers and also harmfully and erroneously supports discriminatory social norms and legislation. To work towards developing effective pedagogical strategies that teach the complexity of biology of sex topics, we used the knowledge in pieces (KiP) theoretical framework to explore the question, how did students' knowledge of sex and sex determination change after a revised unit that centered biologically diverse examples and biological mechanisms in an advanced undergraduate level developmental biology course. Twenty-five of the 48 enrolled students participated in our study. We analyzed students' responses to a reflection and a pre/post assessment using reflexive thematic analysis and compared students' exam responses to multiple choice questions about biology of sex topics and other topics. Our qualitative and quantitative results demonstrated that the expanded unit had mixed effectiveness. From their reflections, students indicated that they thought learning about biology of sex topics was important as part of their biology education and identified the current cultural climate as a reason for discussing, not avoiding, these topics. However, students disproportionately struggled with learning this content. On the exam questions, students performed more poorly on the biology of sex topics than on the other topics covered on the same exam. Their pre/post assessments revealed that student responses changed to responses aligned with the course content more easily for subtopics that were more likely to be novel than for more familiar and often socially charged subtopics. These results demonstrate that seemingly simple topics that are societally entrenched, such as defining the concept of sex, may be more difficult to shift than more conceptually complex concepts that are less entrenched.
Synopsis Sex encompasses a suite of concepts and phenomena that are important for many biological processes and manifest differently across organismal diversity. Scientific progress in understanding sex, across taxonomic and disciplinary specializations, has substantially expanded knowledge of sexual diversity and complexity. This expansion is arguably transformative; however, its accessibility to and impact on nonspecialists remains limited. Common understandings of sex are often centered in human experience and a narrow subset of organismal diversity, shaped by entwined social/scientific histories. Meanwhile, political efforts to define “biological truth” and limit understanding of sexual diversity harm people and science. Improving the integration of knowledge about sex can increase its accessibility, offer new insights, and serve as a foundation for future research. Our symposium brought together researchers across disciplinary and taxonomic expertise to consider sex broadly, decentering animals and working toward broader integrative frameworks. It also included an education workshop and session of talks aimed to improve teaching about sex-related biology. Here, we discuss the symposium contributions and key themes, introducing the papers in this issue. We suggest ways to move forward, informed by discussions at the symposium.
Divergent selection between the sexes may enable parasites to better infect one host sex over the other, potentially leading to sex-biased parasitism. Hosts also typically harbor a component community of parasite species that can vary across a spatial scale. We explored spatial variation in sex-biased parasitism in mangrove rivulus (Kryptolebias marmoratus), an androdioecious fish in which simultaneous hermaphrodites can facultatively transition to male. Using cup traps deployed in the mangroves, we sampled populations that varied in sex ratio; three with relatively high and low percentages of males in Belize and the Florida Keys, respectively. Fish were sexed, and their external bodies and all organs were examined for parasites using microscopy. Hermaphrodites had significantly higher parasite species diversity overall (Simpson's index). Sex differences existed for only one parasite species (heart-specific Ascocotyle sp. digenean metacercariae), with significantly male-biased parasitism in one Belizean population and significantly hermaphrodite-biased parasitism in another. Host mass also predicted the abundance of some parasite species independent of sex: larger individuals had higher abundances of gill-specific and heart-specific Ascocotyle sp. digenean metacercariae. Parasite species diversity (Simpson's index) and richness were higher in Belize than the Florida Keys. While males are often the more heavily parasitized sex, our study did not support this, and our results indicate that host-parasite interactions are driven by a complex relationship between host sex, body mass, geography, and parasite species.
Flying insects achieve extraordinary locomotor performance through diverse combinations of physiological, morphological, and mechanical traits, exemplifying the many-to-one mapping between biological components and emergent flight behavior. Here, we argue that the moth superfamily Bombycoidea is a tractable and compelling emerging model clade that facilitates integration between controlled experimentation and phylogenetically informed comparative analyses, complementing single-species studies to understand the evolution of insect flight. Bombycoidea is a monophyletic group with a well-resolved phylogeny that includes approximately 6000 described species in 10 families distributed globally. Bombycoidea includes the hawkmoths (Sphingidae) and wild silkmoths (Saturniidae), which are known for their contrasting life history and flight behavioral strategies. Most hawkmoths perform agile hover feeding behavior, while silkmoths display erratic flight behavior and do not feed as adults, limiting the silkmoth energy budget. Hawkmoths and silkmoths perform divergent flight behaviors using different combinations of wing shape, size, and kinematics. In addition to the stark divergence in flight behavior and related traits, hawkmoths and silkmoths have extensive interspecific variation, including multiple examples of convergent evolution in life history (e.g., loss of functional adult mouth parts), wing morphologies (e.g., hindwing tails), and wing patterning (e.g., hindwing spots) that occur both within and between these two families and across other bombycoid families. Hawkmoths also include the Tobacco hornworm (Manduca sexta), and extensive research on flight in this species provides a foundation needed for comparison across Bombycoidea. These features of Bombycoidea, in addition to the recent advancements in technology, enable a tractable avenue for large-scale comparative work at unprecedented scales and resolution. Finally, we highlight recent advances in insect flight research using bombycoid moths and outline how this clade can inform future studies aimed at uncovering general principles of insect flight, animal behavior, and locomotion.
Climate change has drastically altered ecosystems world-wide, making animal population data from before the modern era (<1950 CE) essential for establishing accurate baselines against which these changes can be measured. As a mineralized tissue composed of organic and inorganic materials, bone can archive ecological, physiological, and genetic data. Zooarchaeologists and archaeologists have developed extensive research disciplines using bones to study animal population changes over broad time periods; however, these approaches are underutilized in studies of marine mammal species. Here, we present a practical beginner's guide for marine mammal biologists who are interested in using bone as a tool to perform retrospective studies on animal physiology, ecology, genetics, and conservation. Specifically, we give a brief overview of bone biology and the biomarkers preserved in different bone components. We provide suggested methods and best practices for destructive sampling and maximizing analyte data from small bone sample sizes, while also noting methodological limitations. We present a case study that highlights the use of bone to collect ecological, physiological, genetic, and biometric data for the Pacific walrus. Finally, we provide a conceptual guide that helps researchers identify the best methods for investigating their research question(s) of interest. We suggest bone is a critical tissue to address questions related to how adaptable marine mammal populations are to their rapidly changing environments in the postindustrial era.
Acoustic deterrents have been deployed with variable success to decrease fish interactions with anthropogenic hazards (i.e., power plant intakes and spillways) and prevent the spread of invasive species. Acoustic deterrents are nonphysical barriers that offer many advantages in that sound can travel a great distance, are relatively independent of light and weather conditions, do not interfere with navigation and are relatively inexpensive to implement. Assessing the efficacy of deterrents is challenging as there are few controlled or long-term studies and many reports fail to specify sound parameters (i.e., intensity, frequency) preventing independent assessment. It is imperative to factor fish sensory physiology when designing nonphysical deterrents as fish need to detect, localize, and move away from the stimulus. The auditory sensitivity of the target species must be identified to optimize the acoustic stimulus and the ambient soundscape mapped to ensure the sound intensity will be effective. Animals may habituate to an aversive stimulus and therefore multimodal deterrents may prove more effective than single-modal systems. This paper will provide an overview of acoustic deterrents, species targeted, and their efficacy. Special emphasis will be given to efforts to block the upstream migration of invasive bigheaded carp in the Mississippi River basin that currently threatens the Laurentian Great Lakes. Recent studies using a multimodal acoustic deterrent that conditions fish to associate sound with carbon dioxide will be described.
Gas exchange requires a permeable respiratory surface, yet the same permeability also creates a pathway for water loss, posing a particular challenge for organisms whose respiratory surfaces are directly exposed to the terrestrial environment. Woodland salamanders (Plethodon) are a diverse radiation of lungless, terrestrial amphibians that rely entirely on cutaneous respiration, coupling gas exchange and water loss through a shared surface. Whether this shared surface produces a consistent relationship between water loss and metabolic rate across species, or whether the two traits can diverge despite their functional link, remains unresolved. Here, we quantified metabolic rate, water loss rate, and the ratio between these traits across 30 Plethodon species and related these traits to elevational distributions, geographic range size, and climatic conditions across species' ranges. We also compared the relationship between gas exchange and water loss in Plethodon to that observed across a broader set of amphibian taxa. Metabolic rate and water loss were not tightly correlated across Plethodon, despite a positive association across amphibians more broadly. Instead, physiological traits correlated with different aspects of species' elevational limits, range sizes, and climatic niches. Metabolic rate was most consistently associated with elevation and climate, with lower values observed in species occupying higher, cooler environments. Water loss alone showed weaker and less consistent environmental associations, but the transpiration ratio varied with elevational limits such that species extending into lower-elevation environments exhibited greater hydric efficiency. These patterns were also reflected in phylogenetic path analyses, which supported lower elevational limit as a mediator linking physiology to geographic range size. These results suggest that although cutaneous respiration imposes broad hydric costs across amphibians, Plethodon species do not show a single, shared pattern of physiological coupling between gas exchange and water loss.
Sexual reproduction in eukaryotes typically involves the merging of gametes, cells, or nuclei belonging to different mating classes, such as small and large gametes, mating types, or sexes. In this review, we combine theoretical results, recent genomic data, and documented changes in mating systems among ciliate, fungal, plant, algal, and animal lineages to identify general patterns in the evolution of mating classes and their underlying genetic architectures. We emphasize how interactions among distinct coexisting "layers" of mating classes within a species (e.g., anisogamy plus self-incompatibility systems) have shaped their evolution. We raise key unresolved questions, including why no species appears to maintain more than three coexisting layers of mating classes.
Small insects utilize atmospheric flows to facilitate appetitive and migratory behaviors. In the convective and nocturnal boundary layers, these insects may experience high-speed updrafts which can present significant aerodynamic challenges. While it is known from field observations that small insects resist these updrafts, how they do so while maintaining flight stability is unknown. Here we investigate the flight behavior of two insect species, the 3-mm fruit fly (Drosophila melanogaster) and the 2-mm fungus gnat (Lycoriella ingenua), while exposed to quiescent air and to a steady 0.433 m s-1 upward flow within a vertical wind tunnel. We used high-speed 3D photogrammetry to capture flight trajectories and wing and body kinematics. Both species maintained a constant vertical flight velocity in quiescent conditions and in the updraft by maintaining a consistent beat frequency while significantly reducing their stroke amplitude (and thus saving energy), though with some size-specific differences. The smaller fungus gnats kept the dorsal portion of their stroke more so than the larger fruit flies, thereby maintaining the lift-generating clap-and-fling mechanism which is generally required at the lower Reynolds numbers at which they operate. Both species also maintained a similar relative flow velocity, which combines wing tangential velocity and animal velocity with respect to the free stream. Finally, the updraft somewhat affected flight stability in the fungus gnat (as seen in its more sinuous flight trajectories) but not in the fruit fly, which did not change the sinuosity of its trajectories in the updraft. These findings provide a bridge between large- and small-scale studies of small insects in the atmosphere.
Synopsis Environmental changes driven by human activities are exposing organisms to novel and increasingly variable selective pressures. Among many possible responses, behavior stands out as rapid and often reversible mechanisms by which individuals adjust to altered conditions. By shaping how organisms interact with their environments, behaviors can influence exposure to challenges, mediate interactions with other components of the phenotype, such as physiology, morphology, or life history, and ultimately affect ecological and evolutionary outcomes. Despite their potential importance, behavioral responses to anthropogenic changes are not as well integrated across systems and disciplines. Here, we synthesize current research drawn from discussions at a symposium focused on the role behavior plays in confronting a rapidly changing world. We integrate insights across taxa and across major forms of human-driven environmental change, including sensory pollution, urbanization, wildfire, habitat modification, and climate change. Across contexts, we examine how behaviors interact with physiology, life history, ecology, and evolution, emphasizing the need to understand behavior as part of a dynamic and interconnected system in which plastic responses can buffer, redirect, or amplify the effects of environmental change. We identify common themes in how behaviors respond to different anthropogenic challenges, as well as key differences related to ecological context or biological constraint. We also highlight persistent gaps in knowledge, particularly regarding when behavioral flexibility is sufficient to mitigate environmental challenges, how behaviors interact with other traits over different timescales, and when behavioral flexibility may constrain or facilitate evolutionary responses. By synthesizing current knowledge and identifying priorities for future research, we advance an integrative approach to understanding the role of behavior in anthropogenic change. In doing so, we aim to promote cross-system comparisons and collaboration while also clarifying the conditions under which behavioral plasticity plays a critical role in shaping organismal resilience in an increasingly human-altered world.
