Testing the greater male variability phenomenon: male mountain chickadees exhibit larger variation in reversal learning performance compared with females.
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ABSTRACT:
SUBMITTER: Branch CL
PROVIDER: S-EPMC7423667 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Anthropogenic environments are a dominant feature of the modern world; therefore, understanding which traits allow animals to succeed in these urban environments is especially important. Overall, generalist species are thought to be most successful in urban environments, with better general cognition and less neophobia as suggested critical traits. It is less clear, however, which traits would be favoured in urban environments in highly specialized species. Here, we compared highly specialized food-caching mountain chickadees living in an urban environment (Reno, NV, USA) with those living in their natural environment to investigate what makes this species successful in the city. Using a 'common garden' paradigm, we found that urban mountain chickadees tended to explore a novel environment faster and moved more frequently, were better at novel problem-solving, had better long-term spatial memory retention and had a larger telencephalon volume compared with forest chickadees. There were no significant differences between urban and forest chickadees in neophobia, food-caching rates, spatial memory acquisition, hippocampus volume, or the total number of hippocampal neurons. Our results partially support the idea that some traits associated with behavioural flexibility and innovation are associated with successful establishment in urban environments, but differences in long-term spatial memory retention suggest that even this trait specialized for food-caching may be advantageous. Our results highlight the importance of environmental context, species biology, and temporal aspects of invasion in understanding how urban environments are associated with behavioural and cognitive phenotypes and suggest that there is likely no one suite of traits that makes urban animals successful.
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Project description:Sex differences exist in behaviors, disease and neuropsychiatric disorders. Sexual dimorphisms however, have yet to be studied across the whole brain and across a comprehensive time course of postnatal development. Here, we use manganese-enhanced MRI (MEMRI) to longitudinally image male and female C57BL/6J mice across 9 time points, beginning at postnatal day 3. We recapitulate findings on canonically dimorphic areas, demonstrating MEMRI's ability to study neuroanatomical sex differences. We discover, upon whole-brain volume correction, that neuroanatomical regions larger in males develop earlier than those larger in females. Groups of areas with shared sexually dimorphic developmental trajectories reflect behavioral and functional networks, and expression of genes involved with sex processes. Also, post-pubertal neuroanatomy is highly individualized, and individualization occurs earlier in males. Our results demonstrate the ability of MEMRI to reveal comprehensive developmental differences between male and female brains, which will improve our understanding of sex-specific predispositions to various neuropsychiatric disorders.
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2021-10-24 | GSE159861 | GEO
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