Social dominance status is associated with differences in spatial cognitive flexibility in wild mountain chickadees

Social dominance has long been used as a model to investigate social
stress. However, many studies using such comparisons have been performed
in captive environments. These environments may produce unnaturally high
antagonistic interactions, exaggerating the stress of social subordination
and any associated adverse consequences. One such adverse effect concerns
impaired cognitive ability, often thought to be associated with social
subordination. Here, we tested whether social dominance rank is associated
with differences in spatial learning and memory and in reversal spatial
learning (flexibility) abilities in wild food-caching mountain chickadees
at different montane elevations. Higher dominance rank was associated with
higher spatial cognitive flexibility in harsh environments at higher
elevations, but not at lower, milder elevations. In contrast, there were
no consistent differences in spatial learning and memory ability
associated with dominance rank. Our results suggest that spatial learning
and memory ability in specialized food-caching species is a stable trait
resilient to social influences. Spatial cognitive flexibility, on the
other hand, appears to be more sensitive to environmental influences
including social dominance. These findings contradict those from
laboratory studies and suggest that it is critical to investigate the
biological consequences of social dominance under natural conditions.