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Winter Warming Affects The Onset Of Reproduction But Not Cognition Or The Hippocampus In Black-Capped Chickadees (Poecile Atricapillus), Robert J. Martin
Winter Warming Affects The Onset Of Reproduction But Not Cognition Or The Hippocampus In Black-Capped Chickadees (Poecile Atricapillus), Robert J. Martin
Electronic Thesis and Dissertation Repository
The effects of overwinter temperature on behaviour and cognition, hippocampal volume, and reproductive timing were studied in Black-capped chickadees (Poecile atricapillus). I hypothesized that overwinter temperature would have varied effects for Black-capped chickadees that overwinter in northern climates. I found that temperature had no effect on behaviour and cognition, or hippocampal volume, but temperature did influence reproductive timing. Birds that experienced warmer winter conditions had significantly more developed gonads than birds that experienced colder conditions. These results suggest that while birds are clearly sensitive to ambient winter temperature, temperature only modulates some processes and not all. These studies …
Sex And Seasonal Differences In Cognition And The Brain In Brood-Parasitic Brown-Headed Cowbirds (Molothrus Ater), Mélanie F. Guigueno
Sex And Seasonal Differences In Cognition And The Brain In Brood-Parasitic Brown-Headed Cowbirds (Molothrus Ater), Mélanie F. Guigueno
Electronic Thesis and Dissertation Repository
The hypothesis underlying all of neuroecology proposes that natural selection can modify cognition and its neural mechanisms if these modifications enhance fitness. I tested for sex and seasonal differences in cognition and the brain of brood-parasitic brown-headed cowbirds (Molothrus ater) and the closely related non-brood-parasitic red-winged blackbird (Agelaius phoeniceus) to determine whether cognitive and neural patterns were associated with space use and singing in the wild. Cowbirds show a reversal of sex-typical space use often seen in mammals with only female cowbirds parasitizing, searching for, and revisiting host nests. Cowbird and blackbird males sing more than …