36 results match your criteria: "School of Biology University of St Andrews[Affiliation]"

The existence of life-history trade-offs is a fundamental assumption of evolutionary biology and behavioural ecology, yet empirical studies have found mixed evidence for this. Such trade-offs are expected when individuals vary in how they allocate their limited resource budgets between different life-history functions (variation in resource allocation), but they may be masked when individuals vary in how many resources they have acquired that they can later allocate to life-history functions (variation in resource acquisition). We currently lack studies on the extent to which individual differences in behaviour reflect variation between individuals in resource acquisition and resource allocation.

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Article Synopsis
  • Sexual selection involves multiple interacting processes, which can either support or conflict with each other; in the seed bug, there's weak pre-copulatory selection but strong post-copulatory selection.
  • About 40%-60% of mating attempts result in failure, particularly affecting smaller females, who are less likely to be inseminated due to a male preference for larger females.
  • Research indicates that sperm competition primarily depends on copulation duration, with longer copulations enhancing male paternity share, while the influence of female size on paternity is minimal, suggesting a relative independence between cryptic male choice and sperm competition in this species.
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One yet unresolved question in the study of mating system evolution is the occurrence of mating failure, when individuals go through their lives without successfully mating. This includes the failure to produce offspring even following copulation, for instance due to insemination or fertilisation failure. Copulations are costly in a variety of ways, but also a fundamental route to fitness in sexual species, and so we should expect that engaging in copulations that generate no offspring should be strongly selected against.

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Organism condition plays an important role in sexual selection. Sexual ornaments and displays can be condition-dependent, reflecting either underlying genetic quality, experience of environmental stressors, or both. As such, the phenotypic expression of such traits, and the resulting patterns of mate choice acting on them, may be shaped by intrinsic genetic quality and the environment.

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Humans cooperate to build complex structures with culture-specific architectural styles. However, they are not the only animals to build complex structures nor to have culture. We show that social groups of white-browed sparrow weavers () build structures (nests for breeding and multiple single-occupant roosts for sleeping) that differ architecturally among groups.

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Extracellular vesicles (EVs) frequently express human leukocyte antigen class I (HLA-I) molecules. The immunopeptidomes presented on EV HLA-I are being mapped to provide key information on both specific cancer-related peptides, and for larger immunopeptidomic signatures associated with disease. Utilizing HLA-I immunoisolation and mass spectrometry, we characterised the HLA-I immunopeptidome of EVs derived from the melanoma cancer cell line, ESTDAB-026, and the plasma of 12 patients diagnosed with advanced stage melanoma, alongside 11 healthy controls.

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How Important Is Sexual Isolation to Speciation?

Cold Spring Harb Perspect Biol

April 2024

Centre for Biological Diversity, School of Biology University of St Andrews, St Andrews KY16 9ST, United Kingdom.

A central role for sexual isolation in the formation of new species and establishment of species boundaries has been noticed since Darwin and is frequently emphasized in the modern literature on speciation. However, an objective evaluation of when and how sexual isolation plays a role in speciation has been carried out in few taxa. We discuss three approaches for assessing the importance of sexual isolation relative to other reproductive barriers, including the relative evolutionary rate of sexual trait differentiation, the relative strength of sexual isolation in sympatry, and the role of sexual isolation in the long-term persistence of diverging forms.

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Aggressive behaviour is thought to have significant consequences for fitness, sexual selection and the evolution of social interactions, but studies measuring its expression across successive encounters-both intra- and intersexual-are limited. We used the field cricket to evaluate factors affecting repeatability of male aggression and its association with mating success. We quantified focal male aggression expressed towards partners and received from partners in three successive, paired trials, each involving a different male partner.

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Standard occupancy models enable unbiased estimation of occupancy by accounting for observation errors such as missed detections (false negatives) and, less commonly, incorrect detections (false positives). Occupancy models are fitted to data from repeated site visits in which surveyors record evidence of species presence. Use of indirect sign (e.

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Speciation with gene flow is now widely regarded as common. However, the frequency of introgression between recently diverged species and the evolutionary consequences of gene flow are still poorly understood. The group of contains 12 species that are geographically widespread and show varying levels of prezygotic and postzygotic isolation.

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Environmental variables are often the primary drivers of species' distributions as they define their niche. However, individuals, or groups of individuals, may sometimes adopt a limited range within this larger suitable habitat as a result of social and cultural processes. This is the case for Eastern Caribbean sperm whales.

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The nonbreeding period represents a significant part of an Afro-Palearctic migratory bird's annual cycle. Decisions such as whether to remain at a single site and whether to return to it across years have important effects on aspects such as survival, future breeding success, migratory connectivity, and conservation. During this study, we color-ringed 337 common Whitethroats and undertook daily resightings to understand site persistence and the degree of site fidelity throughout three nonbreeding periods (November-April) in Nigeria.

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Animals make a diverse array of architectures including nests, bowers, roosts, traps, and tools. Much of the research into animal architecture has focused on the analysis of physical properties such as the dimensions and material of the architectures, rather than the behavior responsible for creating these architectures. However, the relationship between the architecture itself and the construction behavior that built it is not straightforward, and overlooking behavior risks obtaining an incomplete or even misleading picture of how animal architecture evolves.

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There is tantalizing evidence that phenotypic plasticity can buffer novel, adaptive genetic variants long enough to permit their evolutionary spread, and this process is often invoked in explanations for rapid adaptive evolution. However, the strength and generality of evidence for it is controversial. We identify a conceptual problem affecting this debate: recombination, segregation, and independent assortment are expected to quickly sever associations between genes controlling novel adaptations and genes contributing to trait plasticity that facilitates the novel adaptations by reducing their indirect fitness costs.

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Precopulatory courtship plays an essential role in the insemination process and influences postcopulatory behavior between males and females. Male precopulatory oral stimulation of female genitals is rare for invertebrates. Here, we describe an intriguing oral sexual courtship in a cryptic desert beetle Faldermann.

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Among the parasites of insects, endoparasitoids impose a costly challenge to host defenses because they use their host's body for the development and maturation of their eggs or larvae, and ultimately kill the host. Tachinid flies are highly specialized acoustically orienting parasitoids, with first instar mobile larvae that burrow into the host's body to feed. We investigated the possibility that field crickets employ postinfestation strategies to maximize survival when infested with the larvae of the parasitoid fly .

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The evolution of reproductive isolation lies at the heart of understanding the process of speciation. Of particular interest is the relationship between pre- and postzygotic reproductive isolation, and the genetic architecture of traits that contribute to one or both forms of reproductive isolation. The sibling species of seed bug and .

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There has been growing emphasis on the role that crop wild relatives might play in supporting highly selected agriculturally valuable species in the face of climate change. In species that were domesticated many thousands of years ago, distinguishing wild populations from escaped feral forms can be challenging, but reintroducing variation from either source could supplement current cultivated forms. For economically important cabbages (Brassicaceae: ), "wild" populations occur throughout Europe but little is known about their genetic variation or potential as resources for breeding more resilient crop varieties.

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Heterogeneity in resources is a ubiquitous feature of natural landscapes affecting many aspects of biology. However, the effect of environmental heterogeneity on the evolution of cooperation has been less well studied. Here, using a mixture of theory and experiments measuring siderophore production by the bacterium as a model for public goods based cooperation, we explore the effect of heterogeneity in resource availability.

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Negative frequency-dependent selection (NFDS) has been shown to maintain polymorphism in a diverse array of traits. The action of NFDS has been confirmed through modeling, experimental approaches, and genetic analyses. In this study, we investigated NFDS in the wild using morph-frequency changes spanning a 20-year period from over 30 dimorphic populations of .

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Evolutionary adaptation is generally thought to occur through incremental mutational steps, but large mutational leaps can occur during its early stages. These are challenging to study in nature due to the difficulty of observing new genetic variants as they arise and spread, but characterizing their genomic dynamics is important for understanding factors favoring rapid adaptation. Here, we report genomic consequences of recent, adaptive song loss in a Hawaiian population of field crickets ().

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A challenge in the Bachelor's studies in Biology is to strike a balance between reducing the teaching of practical scientific experiments to what is feasible in a short time, and teaching "real" science in undergraduate laboratories for high numbers of participants. We describe a laboratory in behavioral biology, with the primary focus on the student learning. However, also the underlying scientific question and the results of the experiment, namely the behavior of the three-spined stickleback () in a trade-off situation during foraging, is without a doubt timely and sufficient for scientific studies on this subject, and this through the experiments conducted and data collected by the students.

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Haplodiploidy has evolved repeatedly among invertebrates, and appears to be associated with inbreeding. Evolutionary biologists have long debated the possible benefits for females in diplodiploid species to produce haploid sons-beginning their population's transition to haplodiploidy-and whether inbreeding promotes or inhibits this transition. However, little attention has been given to what makes a haploid individual male rather than female, and whether the mechanism of sex determination may modulate the costs and benefits of male haploidy.

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Evolution of altruistic behavior was a hurdle for the logic of Darwinian evolution. Soon after Hamilton formalized the concept of inclusive fitness, which explains how altruism can evolve, he suggested that the high sororal relatedness brought by haplodiploidy could be why Hymenopterans have a high prevalence in eusocial species, and why helpers in Hymenoptera are always female. Later it was noted that in order to capitalize on the high sororal relatedness, helpers would need to direct help toward sisters, and this would bias the population sex ratio.

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