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Biology subjects

Reale, D.

Publications and source records attributed to Reale, D..

4 recordsLinked to original sources

Tit wit: environmental and genetic drivers of cognitive variation along an urbanization gradient

Cognitive abilities can promote acclimation and adaptation to life in cities. However, the genetic versus environmental drivers of cognition have rarely been studied in the wild and there exists a major gap concerning the role of cognition in adaptation to novel urban contexts. To address this, we evaluate cognitive variation in wild great tits (Parus major; N = 393) along an urban gradient, and decipher the genetic basis of this variation using a combination of a common garden experiment, quantitative genetic analyses, and genome-wide association studies. Specifically, we measure inhibitory control abilities which affect how animals respond to novel resources and challenges. We find that wild urban and forest tits do not clearly differ in inhibitory control performance (number of errors or the latency to escape) during a motor detour task; a result that was consistent in birds from urban and forest origins reared in a common garden (N = 73). Cognitive performance was repeatable (R = 0.35 - 0.38) and showed low to moderate heritability in the wild (h2= 0.16 - 0.28 using social and genomic pedigrees). We identified five SNPs that were significantly associated with the number of errors during the task, explaining 21% of the cognitive variation. These SNPs are linked to genes related to serotonergic and dopaminergic systems that are known to play important roles in cognition. Altogether, our study finds limited evidence that inhibitory control abilities have evolved under novel urban contexts, yet reveals a genetic basis of this cognitive trait in great tits.

animal behavior and cognition↗

A global meta-analysis reveals more variable life histories in urban birds compared to their non-urban neighbours

Cities pose a major ecological challenge for wildlife worldwide. Phenotypic variation, which can result from underlying genetic variation or plasticity, is an important metric to understand eco-evolutionary responses to environmental change. Recent work suggests that urban populations might have higher levels of phenotypic variation than non-urban counterparts. This prediction, however, has never been tested across species nor over a broad geographical range. Here, we conduct a meta-analysis of the avian literature to compare urban versus non-urban means and variation in phenology (i.e., lay date) and reproductive effort (i.e., clutch size, number of fledglings). First, we show that urban populations reproduce earlier and have smaller broods than non-urban conspecifics. Second, we show that urban populations have higher phenotypic variation in laying date than non-urban populations. This result arises from differences between populations within breeding seasons, conceivably due to higher landscape heterogeneity in urban habitats. These findings reveal a novel effect of urbanisation on animal life-histories with potential implications for species adaptation to urban environments (which will require further investigation). Higher variation in phenology in birds subjected to urban disturbance could result from plastic responses to a heterogeneous environment, or from higher genetic variation in phenology, possibly linked to higher evolutionary potential.

evolutionary biology↗

Links between mouse and vole social networks and their gut microbiomes support predictions from metacommunity theory

Metacommunity theory predicts that strongly connected individuals will harbour similar gut microbiomes (GMs) and affiliating with more individuals should increase GM diversity. Additionally, cross-species bacterial transmission may play a role in how interspecific interactions affect host community dynamics. We tracked sympatric mice (Peromyscus maniculatus) and voles (Myodes gapperi) and constructed social networks for each species and both species together. We tested whether: 1) similarity in GM composition between individuals correlates with their social proximity within and across species; 2) GM diversity correlates with a hosts number of conspecific or heterospecific neighbours. We could not differentiate associations between GM composition and mouse social proximity or habitat. In voles, social proximity explained part of the GM composition. GM composition associated with interspecific social proximity, and mouse GM diversity correlated with number of vole neighbours. Contributions of host-host bacterial transmission to the GM partly follow metacommunity theory but depend on host species.

ecology↗

Gut microbiome modulates behaviour and life history in two wild rodents

Laboratory studies demonstrate that the gut microbiome can regulate host anxiety and exploratory behaviour. While this has implications for human health, it could have ecological and evolutionary implications for wild populations, a hitherto untested hypothesis. We tested whether the microbiome can directly modulate host behaviour and thereby affect life history in wild mice (Peromyscus maniculatus) and voles (Myodes gapperi). We compared the microbiome composition, exploration and anxiety behaviours, and home range of mice and voles before and after chronic antibiotic treatment and measured survival during treatment. Treated animals had lower diversity and relative abundance of most bacterial phyla save for Proteobacteria which increased in relative abundance. In mice, antibiotic treatment increased exploration and decreased home range without impacting survival. In voles, it lowered survival such that we could not test its effect on behaviour. Therefore, the microbiome can directly impact behaviour and host life history in the wild.

ecology↗