Biology subjects

Jarrett, B. J. M.

Publications and source records attributed to Jarrett, B. J. M..

3 recordsLinked to original sources

bioRxiv2024

Divergent selection and plasticity shape reproductive isolation at the onset of speciation

Reproductive isolation is a key process during speciation, but the factors that shape its evolution during the early stages of speciation remain largely unknown. Using a meta-analysis of 34 experimental speciation studies, we show that populations that experience divergent selection evolved stronger reproductive isolation compared to populations that evolved in similar environments, consistent with ecological speciation theory. However, and contrary to predictions, reproductive isolation did not increase with the number of generations. We present evidence that phenotypic plasticity could play a role in explaining these results, as divergent environments induce an increase in reproductive isolation in the first few generations. Our results highlight that adaptation to different environments in conjunction with plasticity can lead to a rapid increase in reproductive isolation at the beginning of speciation.

evolutionary biology↗

bioRxiv2022

Multilevel selection leads to divergent coadaptation of care-giving parents during pre-hatching parental care

The joint actions of animals in partnerships or social groups evolve under both natural selection, from the wider environment, and social selection, imposed by other members of the pair or group. We used experimental evolution to investigate how jointly expressed actions evolve upon exposure to a new environmental challenge. Our work focused on the evolution of carrion nest preparation by pairs of burying beetles Nicrophorus vespilloides, a joint activity undertaken by the pair but typically led by the male. In previous work, we found that carrion nest preparation evolved to be faster in experimental populations without post-hatching care (No Care lines) than with post-hatching care (Full Care lines). Here we investigate how this joint activity evolved. After 15 generations of experimental evolution, we created heterotypic pairs (No Care females with Full Care males, and No Care males with Full Care females) and compared their carrion nest making with homotypic No Care and Full Care pairs. We found that pairs with No Care males prepared the nest more rapidly than pairs with Full Care males, regardless of the females line of origin. This suggests that males led the way by adapting their nest preparation behaviour to the No Care environment first, with females secondarily co-adapting their behaviour to the males behaviour by reducing their nest preparation behaviour. We discuss how social coadaptations within pairs or groups could act as a post-mating barrier to gene flow.

evolutionary biology↗

bioRxiv2017

Social interactions within the family enhance the capacity for evolutionary change

Classical models of evolution seldom predict evolution in the wild. One explanation is that the social environment has important, yet overlooked, effects on how traits change in response to natural selection. We tested this idea with selection experiments on burying beetles (Nicrophorus vespilloides), sub-social insects that exhibit biparental care. Populations responded to selection for larger adults only when parents cared for their offspring, and responded to selection for smaller adults only when we prevented parents from providing care. Comparative analyses revealed a similar pattern: evolutionary increases in species size within the genus Nicrophorus are associated with the obligate provision of care. Synthesising our results with previous studies, we suggest that cooperative social environments enhance the response to selection whereas conflict can prevent further directional selection.

evolutionary biology↗