The bigger brains of humans have allowed
Parrots are known for their incredible ability to think and their long lives. A study conducted by Max Planck researchers has shown that one of these characteristics could be a result of the other. Through a study of 217 species of parrots, they discovered that certain species, like the scarlet macaw and the sulfur-crested cockatoos, have exceptionally long lifespans on average, that can exceed 30 years.
This is typically only seen when birds are large. Blue Birds in Michigan Additionally, they identified an explanation for these lengthy lifespans by examining the size of their brains relative to each other. This study is the first to demonstrate a link between the size of the brain and longevity in parrots. This suggests that an increase in cognitive abilities could aid parrots in navigating the dangers of their environment, and also to live longer lives.
Although parrots are recognized for their long
lives and sophisticated cognitive abilities as well as their lifespans and brain size that is comparable to primates, there is no way to determine whether these two characteristics have had an impact on one another. “The issue has been finding reliable data of high quality,” says Simeon Smeele who is a doctoral student in the
Max Planck Institute of Animal Behavior and the lead author of the study. Finding out what drives the longevity of parrots is only possible by comparing live parrots. “Comparative studies of life history require large samples to ensure certainty, as there are many different processes going on simultaneously, which causes lots of variations,” says Steele.
In order to collect a sufficient sample size researchers at the Max Planck Institute of Animal Behavior and the Max Planck Institute for Evolutionary Anthropology in Leipzig joined forces with Species360 which is based on records of animals from zoos as well as aquariums.
Together, they collected information
from more than 130,000 parrots from more than a thousand Zoos. This database allowed the team to gain the first reliable estimates of the average life span of 217 parrot species–representing over half of all known species. The study revealed a stunning variation in life expectancy that ranges from a minimum of about two years with the fig parrot to a minimum of thirty years in the case of macaw with scarlet.
Other species that live long include the cockatoo that has sulfur crested from Australia that lives an average of 25 years. “Living at least 30 years is a rarity in birds this big,” says Smeele who collaborated together with Lucy Aplin from the Max Planck Institute of Animal Behavior and Mary Brooke McElreath from the Max Planck Institute in Leipzig in the research. “Some individuals have a life span of more than 80 years old, which is an acceptable age for humans as well. These figures are quite remarkable when you consider that males weigh around 100x more.”
Analyzing comparatives
The team then conducted the technique of a large-scale comparative study to determine if parrots’ famous cognitive abilities affected their lifespan. They tested two theories first, that having more brains can lead to greater longevity.
Also, more intelligent birds are better able to solve issues when they are in nature, thereby having longer lives. Additionally, larger brains can take longer to develop, and consequently have longer lives. For every species, they gathered data on the size of their brains as well as the average body weight, and developmental factors.
The researchers then merged the data
and then ran simulations for every hypothesis and looked at which model was the most effective in explaining the data. Why Do Birds Suddenly Appear Their findings provide the first evidence to suggest that increasing brain size is a factor in longer lifespans for parrots? Since brain size in relation to body size is an indicator of intelligence, the results suggest that the parrots that had significantly larger brains had the cognitive capacity to overcome
challenges in the wild, which could otherwise cause death and allowed them to live for longer. “This is in line with the belief that larger brains allow species to be more flexible and enable them to last longer,” says Steele. “For instance when they are unable to find of their favorite food items, they might be able to discover something else and be able to survive.”
