Longevity in parrots linked to brain size and cognitive ability

Animal behaviorists have long wondered why certain species of parrots have such long lifespans, considering that they are so small. Researchers from the Max Planck Institute of Animal Behavior and the Max Planck Institute for Evolutionary Anthropology are shedding some new light on the topic. The key to parrot longevity might be found in their brain size and cognitive ability. 

To gather reliable data, the scientists needed to compare living parrots. To get the data, they coordinated with Species360, which contains animal records from zoos and aquariums. Overall, they were able to look at over 130,000 individuals representing 217 species. 

They found that there was a lot of variation in life expectancy between species. The shortest-lived is the fig parrot, with an average lifespan of two years. The longest-lived species is the Scarlet Macaw, with an average life expectancy of 30 years. 

After analyzing the data, the scientists were confident that parrots’ brain size and life expectancy are positively correlated. The question remained… Why? They had two hypotheses. One theory is that larger brains mean that the birds are more intelligent and better able to fend for themselves and avoid predators. The second was that since larger brains take more time to grow, larger birds require longer lifespans. 

After running both hypotheses through models, the researchers determined that the models support the first hypothesis. The scientists believe that large brain sizes relative to body size, have cognitive abilities that allow them to solve problems in their natural environments, allowing the parrots to survive longer. 

“This supports the idea that in general larger brains make species more flexible and allow them to live longer,” said study lead author Simeon Smeele. “For example, if they run out of their favorite food, they could learn to find something new and thus survive.” 

The research team hopes to explore this subject in the future by examining how sociality and cultural learning might influence longevity. 

“Large-brained birds might spend more time socially learning foraging techniques that have been around for multiple generations,” said Smeele. “This increased learning period could potentially also explain the longer life spans, as it takes more time but also makes the foraging repertoire more adaptive.” 

This research is published in Proceedings of the Royal Society B.

—

By Erin Moody , Earth.com Staff Writer