Figures & data
Figure 1 Representative brain section (Hp outlined) and Hp neurons of a black-capped chickadee.
Figure 2 The black-capped chickadee (Poecile atricapillus) is a non-migratory food-caching bird commonly used in studies on the relationship between the environment, the brain and memory. Photograph by TCR.
Figure 3 (A) Locations ranked by climatic severity based on winter period (Nov–March) averages from 1971–2000. Average winter temp (C), average snow depth (mm) and day length (min) during winter solstice. All measures of climate severity decrease as latitude decreases. Data from Roth and Pravosudov.Citation9 (B) Map of black-capped chickadee species range and collection sites across North America. (C) Relative hippocampal volume and total neuron numbers (least squares means) across locations ranked by climate severity. Both chickadee Hp volumes and neuron numbers significantly decreased with latitude and climate severity and correlated perfectly with rank climate variables. Data from Roth and Pravosudov.Citation9
