Biology subjects

Wootton, E.

Publications and source records attributed to Wootton, E..

3 recordsLinked to original sources

bioRxiv2025

The heritability of migration behaviours in a wide-ranging ungulate

Migration behaviour is thought to be declining globally in the face of rapid human-mediated environmental change. While many species exhibit individual plasticity in their migratory behaviour, not all species demonstrate the level of plasticity necessary to adjust to novel conditions. Selection on heritable behaviours might therefore play an important role in the maintenance of migratory phenotypes for some species. Using GPS and genomic data from 242 individuals (256 animal-years) in a pedigree-free quantitative genetic approach, we estimated heritability, repeatability, and sources of environmental variation for migration traits in migrating mule deer (Odocoileus hemionus). We also estimated heritability of body size to ensure validity of our results. Heritability estimates of body size traits were comparable to the current estimates for ungulate body size. We found low heritability for broad patterns of migration timing, distance, and duration, but high heritability for movement rate along the migratory route. Our findings suggest that wild mule deer populations have the potential to respond to selection pressure generated by human activity or global environmental changes through microevolutionary changes in migration behaviours. Significance StatementMigration behaviour is critical for the reproduction and survival of a wide variety of taxa, yet there have been global declines in migrations in the face of rapid human-mediated environmental change. Despite our understanding that variation in migration behaviour has both genetic and environmental components, studies quantifying the sources of genetic variation contributing to migration phenotypes are lacking. Our study provides, to our knowledge, the first empirical evidence of heritability in a migration behaviour in ungulates. These results have implications for the evolution and maintenance of migration behaviours in natural populations.

genetics↗

bioRxiv2022

Genomic health is dependent on population demographic history

Current genetic methods of population assessment in conservation biology have been challenged by genome-scale analyses due to their quantitatively novel insights. These analyses include assessments of runs-of-homozygosity (ROH), genomic evolutionary rate profiling (GERP), and mutational load. Here, we aim to elucidate the relationships between these measures using three divergent ungulates: the white-tailed deer, caribou, and mountain goat. The white-tailed deer is currently expanding, while caribou are in the midst of a significant decline. Mountain goats remain stable, having suffered a large historical bottleneck. We assessed genome-wide signatures of inbreeding using the inbreeding coefficient F and %ROH (FROH) and identified evolutionarily constrained regions with GERP. Mutational load was estimated by identifying mutations in highly constrained elements (CEs) and sorting intolerant from tolerant (SIFT) mutations. Our results show that F and FROH are higher in mountain goats than in caribou and white-tailed deer. Given the extended bottleneck and low Ne of the mountain goat, this supports the idea that the genome-wide effects of demographic change take time to accrue. Similarly, we found that mountain goats possess more highly constrained CEs and the lowest dN/dS values, both of which are indicative of greater purifying selection; this is also reflected by fewer mutations in CEs and deleterious mutations identified by SIFT. In contrast, white-tailed deer presented the highest mutational load with both metrics, in addition to dN/dS, while caribou were intermediate. Our results demonstrate that extended bottlenecks may lead to reduced diversity and increased FROH in ungulates, but not necessarily the accumulation of deleterious alleles, likely due to the purging of deleterious alleles in small populations.

genomics↗

bioRxiv2022

Speciation without gene-flow in hybridizing deer

Under the ecological speciation model, divergent selection acts on ecological differences between populations, gradually creating barriers to gene flow and ultimately leading to reproductive isolation. Hybridisation is part of this continuum and can both promote and inhibit the speciation process. Here, we used white-tailed (Odocoileus virginianus) and mule deer (O. hemionus) to investigate patterns of speciation in hybridising sister species. We quantified genome-wide historical introgression and performed genome scans to look for signatures of four different selection scenarios. Despite ample modern evidence of hybridisation, we found negligible patterns of ancestral introgression and no signatures of divergence with gene flow, rather localised patterns of allopatric and balancing selection were detected across the genome. Genes under balancing selection were related to immunity, MHC and sensory perception of smell, the latter of which is consistent with deer biology. The deficiency of historical gene-flow suggests that white-tailed and mule deer were spatially separated during the glaciation cycles of the Pleistocene and genome wide differentiation accrued via genetic drift. Dobzhansky-Muller incompatibilities and selection against hybrids are hypothesised to be acting, and diversity correlations to recombination rates suggests these sister species are far along the speciation continuum.

evolutionary biology↗