Survival of the Smartest
By Jeff Renaud, University of Western Ontario
Although ‘survival of the fittest’ continues to dominate in the animal kingdom, new research suggests that cognitive skills are also important to natural selection and survival rates.
A decade-long study conducted by Western University animal behavior and cognition researcher Carrie Branch and her collaborators at the University of Nevada, Reno and the University of Oklahoma tracked the spatial cognition and lifespan of 227 mountain chickadees.
They found that birds with
better spatial learning and memory abilities (when it came to understanding
their surroundings and food storage or caching strategies) lived longer.
The study, recently published in Science,
confirms that enhanced cognitive abilities can be associated with a longer
lifespan in wild chickadees.
“Animals have two interests. They want to survive, and they want to reproduce, so the smart thing for them to do is whatever allows those two things to happen. We found for mountain chickadees that means knowing where to collect food, successfully storing it and remembering where they stored it so they can retrieve it later,” said Branch, a psychology professor and a principal investigator at Western’s Advanced Facility for Avian Research, a world-class facility for interdisciplinary studies of bird biology.
Research Findings on Spatial Cognition and Survival
Cognitive ability has long been positioned as a key
indicator for survival and lifespan in animals, but experiments and field tests
often rely on indirect measures of mental capacity, such as brain size.
Chickadees are relatively small birds and correspondingly, have small brains.
Despite this seemingly physical limitation, mountain chickadees performed
extremely well in the series of experiments Branch and her collaborators
designed for them at a remote field site in the Sierra Nevada mountains.
“I think chickadees’ specialized cognitive abilities are a
product of their social dominance structure, but we are still testing that
theory. For now, we can confirm chickadees have figured out how to cache and
recover food using spatial cognition and the ones that do it better, live
longer,” said Branch.
Chickadees are native to North America, where they are very common. A chickadee can hide as many as 80,000 individual seeds, which they retrieve during the winter.
Implications of Cognitive Abilities on Reproduction
Branch and her collaborators tested cognitive abilities in
mountain chickadees using radio frequency-based feeders, which are spatially
organized in groups of eight and feature motorized doors that open
automatically for electronically tagged birds providing food rewards when they
land on the perch.
With more than a decade of data collected, the new study
shows mountain chickadees with the best spatial cognitive abilities will live,
on average, two years longer than those with the worst spatial cognition.
Mountain chickadees breed once per year, with an average clutch size of seven
eggs, and individuals with the best spatial abilities may produce more than
double the number of offspring (i.e. 14 more offspring) than those with poorer
cognition. In past studies, Branch and her collaborators reported females
produce more offspring when paired with “smarter” males.
“This study shows that mountain chickadees with better
spatial cognitive abilities are more likely to live longer, as these abilities
allow them to successfully retrieve cached food while coping with harsh and
unpredictable environments, including extreme weather events caused by climate
change,” said Branch.
Reference: “Spatial cognitive ability is associated with
longevity in food-caching chickadees” by Joseph F. Welklin, Benjamin R.
Sonnenberg, Carrie L. Branch, Virginia K. Heinen, Angela M. Pitera, Lauren M.
Benedict, Lauren E. Whitenack, Eli S. Bridge and Vladimir V. Pravosudov, 5
September 2024, Science.
DOI:
10.1126/science.adn5633