20 results match your criteria: "Centre for Ecology and Conservation University of Exeter Penryn UK.[Affiliation]"
Scoring the penetrance of heterozygotes in complex phenotypes, like colour pattern, is difficult and complicates the analysis of systems in which dominance is incomplete or evolving. The African Monarch () represents an example where colour pattern heterozygotes, formed in the contact zone between the different subspecies, show such intermediate dominance. Colour pattern in this aposematic butterfly is controlled by three loci , and .
View Article and Find Full Text PDFEvolutionary adaptation through genetic change requires genetic variation and is a key mechanism enabling species to persist in changing environments. Although a substantial body of work has focused on understanding how and why additive genetic variance ( ) differs among traits species, we still know little about how they vary species. Here we make a first attempt at testing for interspecific variation in two complementary measures of and the role of phylogeny in shaping this variation.
View Article and Find Full Text PDFThe nests of ground-nesting birds rely heavily on camouflage for their survival, and predation risk, often linked to ecological changes from human activity, is a major source of mortality. Numerous ground-nesting bird populations are in decline, so understanding the effects of camouflage on their nesting behavior is relevant to their conservation concerns. Habitat three-dimensional (3D) geometry, together with predator visual abilities, viewing distance, and viewing angle, determine whether a nest is either visible, occluded, or too far away to detect.
View Article and Find Full Text PDFIn butterflies and moths, male-killing endosymbionts are transmitted from infected females via their eggs, and the male progeny then perish. This means that successful transmission of the parasite relies on the successful mating of the host. Paradoxically, at the population level, parasite transmission also reduces the number of adult males present in the final population for infected females to mate with.
View Article and Find Full Text PDFPassage experiments that sequentially infect hosts with parasites have long been used to manipulate virulence. However, for many invertebrate pathogens, passage has been applied naively without a full theoretical understanding of how best to select for increased virulence and this has led to very mixed results. Understanding the evolution of virulence is complex because selection on parasites occurs across multiple spatial scales with potentially different conflicts operating on parasites with different life histories.
View Article and Find Full Text PDFStudies of parasites in wild animal populations often rely on molecular methods to both detect and quantify infections. However, method accuracy is likely to be influenced by the sampling approach taken prior to nucleic acid extraction. Avian Haemosporidia are studied primarily through the screening of host blood, and a range of storage mediums are available for the short- to long-term preservation of samples.
View Article and Find Full Text PDFReleasing gamebirds in large numbers for sport shooting may directly or indirectly influence the abundance, distribution and population dynamics of native wildlife. The abundances of generalist predators have been positively associated with the abundance of gamebirds. These relationships have implications for prey populations, with the potential for indirect impacts of gamebird releases on wider biodiversity.
View Article and Find Full Text PDFEndemic island species face unprecedented threats, with many populations in decline or at risk of extinction. One important threat is the introduction of novel and potentially devastating diseases, made more pressing due to accelerating global connectivity, urban development, and climatic changes. In the Galápagos archipelago two important wildlife diseases: avian pox ( spp.
View Article and Find Full Text PDFDevil facial tumor disease (DFTD) is a transmissible cancer affecting Tasmanian devils . The disease has caused severe population declines and is associated with demographic and behavioral changes, including earlier breeding, younger age structures, and reduced dispersal and social interactions. Devils are generally solitary, but social encounters are commonplace when feeding upon large carcasses.
View Article and Find Full Text PDFA wide array of technologies are available for gaining insight into the movement of wild aquatic animals. Although acoustic telemetry can lack the fine-scale spatial resolution of some satellite tracking technologies, the substantially longer battery life can yield important long-term data on individual behavior and movement for low per-unit cost. Typically, however, receiver arrays are designed to maximize spatial coverage at the cost of positional accuracy leading to potentially longer detection gaps as individuals move out of range between monitored locations.
View Article and Find Full Text PDFThe ocean is the linchpin supporting life on Earth, but it is in declining health due to an increasing footprint of human use and climate change. Despite notable successes in helping to protect the ocean, the scale of actions is simply not now meeting the overriding scale and nature of the ocean's problems that confront us.Moving into a post-COVID-19 world, new policy decisions will need to be made.
View Article and Find Full Text PDFNutritional geometry has advanced our understanding of how macronutrients (e.g., proteins and carbohydrates) influence the expression of life history traits and their corresponding trade-offs.
View Article and Find Full Text PDFAge-related changes in diet have implications for competitive interactions and for predator-prey dynamics, affecting individuals and groups at different life stages. To quantify patterns of variation and ontogenetic change in the diets of Tasmanian devils , a threatened marsupial carnivore, we analyzed variation in the stable isotope composition of whisker tissue samples taken from 91 individual devils from Wilmot, Tasmania from December 2014 to February 2017. Both δC and δN decreased with increasing age in weaned Tasmanian devils, indicating that as they age devils rely less on small mammals and birds, and more on large herbivores.
View Article and Find Full Text PDFUnderstanding the ecology and evolution of parasites is contingent on identifying the selection pressures they face across their infection landscape. Such a task is made challenging by the fact that these pressures will likely vary across time and space, as a result of seasonal and geographical differences in host susceptibility or transmission opportunities. Avian haemosporidian blood parasites are capable of infecting multiple co-occurring hosts within their ranges, yet whether their distribution across time and space varies similarly in their different host species remains unclear.
View Article and Find Full Text PDFMonitoring postrelease establishment and movement of animals is important in evaluating conservation translocations. We translocated 39 wild pine martens (19 females, 20 males) from Scotland to Wales. We released them into forested areas with no conspecifics in 2015, followed by a second release in 2016, alongside the previously released animals.
View Article and Find Full Text PDFIt is generally thought that the intensification of farming will result in higher disease prevalences, although there is little specific modelling testing this idea. Focussing on honeybees, we build multi-colony models to inform how "apicultural intensification" is predicted to impact honeybee pathogen epidemiology at the apiary scale.We used both agent-based and analytical models to show that three linked aspects of apicultural intensification (increased population sizes, changes in population network structure and increased between-colony transmission) are unlikely to greatly increase disease prevalence in apiaries.
View Article and Find Full Text PDFSocial interactions can give rise to indirect genetic effects (IGEs), which occur when genes expressed in one individual affect the phenotype of another individual. The evolutionary dynamics of traits can be altered when there are IGEs. Sex often involves indirect effects arising from first-order (current) or second-order (prior) social interactions, yet IGEs are infrequently quantified for reproductive behaviors.
View Article and Find Full Text PDFSocial interactions among hosts influence the persistence and spread of infectious pathogens. Daily and seasonal variation in the frequency and type of social interactions will play an important role in disease epidemiology and, alongside other factors, may have an influence on wider disease dynamics by causing seasonal forcing of infection, especially if the seasonal variation experienced by a population is considerable. We explored temporal variation in within-group contacts in a high-density population of European badgers naturally infected with (the causative agent of bovine tuberculosis).
View Article and Find Full Text PDFCamouflage is one of the most widespread antipredator defences, and its mechanistic basis has attracted considerable interest in recent years. The effectiveness of camouflage depends on the interaction between an animal's appearance and its background. Concealment can therefore be improved by changes to an animal's own appearance, by behaviorally selecting an optimal background, or by modifying the background to better match the animal's own appearance.
View Article and Find Full Text PDFThe cooperative breeding hypothesis (CBH) states that cooperative breeding, a social system in which group members help to rear offspring that are not their own, has important socio-cognitive consequences. Thornton & McAuliffe (2015; henceforth T&M) critiqued this idea on both conceptual and empirical grounds, arguing that there is no reason to predict that cooperative breeding should favour the evolution of enhanced social cognition or larger brains, nor any clear evidence that it does. In response to this critique, Burkart & van Schaik (2016 henceforth B&vS) attempt to clarify the causal logic of the CBH, revisit the data and raise the possibility that the hypothesis may only apply to primates.
View Article and Find Full Text PDF