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Laboratory studies show that increased physiological burden during development results in cognitive impairment. In the wild, animals experience a wide range of developmental conditions, and it is critical to understand how variation in such conditions affects cognitive abilities later in life, especially in species that strongly depend on such abilities for survival. We tested whether variation in developmental condition is associated with differences in spatial cognitive abilities in wild food-caching mountain chickadees. Using tail feathers grown during development in juvenile birds, we measured feather corticosterone (Cort f ) levels and growth rates and tested these birds during their first winter on two spatial learning tasks. In only 1 of the 3 years, higher feather Cort f was negatively associated with memory acquisition. No significant associations between feather Cort f and any other measurement of spatial cognition were detected in the other 2 years of the study or between feather growth rate and any measurement of cognition during the entire study. Our results suggest that in the wild, naturally existing variation in developmental condition has only a limited effect on spatial cognitive abilities, at least in a food-caching species. This suggests that there may be compensatory mechanisms to buffer specialized cognitive abilities against developmental perturbations.
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Spatial cognitive ability is associated with longevity in food-caching chickadees
Cognitive abilities are hypothesized to affect survival and life span in nonhuman animals. However, most tests of this hypothesis have relied on interspecific comparisons of indirect measures of cognitive ability, such as brain size. We present direct evidence that individual variation in cognitive abilities is associated with differences in life span in a wild food caching bird. We measured the spatial cognitive abilities and tracked the life span of 227 mountain chickadees (Poecile gambeli) in their natural environment and found that individuals with better spatial learning and memory abilities involved in food caching lived longer. These results confirm that enhanced cognitive abilities can be associated with longer life in wild animals and that selection on cognitive abilities can lead to increased life span.
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- PAR ID:
- 10580290
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science
- Volume:
- 385
- Issue:
- 6713
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 1111 to 1115
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/science.adn5633
