In general, a bird’s lifespan tends to correlate with its size. The chirpy canary, for example, typically weighs less than one ounce and lives to around 10 years old, while the 6.5- to 14-pound bald eagle lives up to 28 years in the wild. But parrots, a remarkably versatile order of more than 350 bird species, defy this rule of thumb, living up to roughly 80 years despite their relatively small stature—the birds weigh between 2.25 ounces to 3.5 pounds on average.
Parrots likely owe this longevity—as well as their superlative intelligence—to evolution. As JoAnna Klein reports for The New York Times, a new analysis of the blue-fronted Amazon parrot’s genome suggests the creatures are as genetically distant from other birds as humans are from other primates. The differences are so striking, according to study co-author Claudio Mello, a neuroscientist at Oregon Health and Science University, that he and his colleagues “think parrots are [humans’] parallel in the avian world.”
The team’s findings, published in Current Biology, juxtapose the blue-fronted parrot—a native Brazilian species known to live up to 66 years—with 30 other species, including four from the parrot family. Elizabeth Hayes of Portland Business Journal writes that the comparative genomic analysis revealed high rates of “conserved mutations” capable of extending smaller birds’ lifespans. These mutations, which Klein notes were seen in both parrots and several similarly long-lived birds, affect a set of 344 genes that appear to be linked with longevity. As Chelsea Whyte adds for New Scientist, the genes reportedly “support DNA damage repair, slow down cell death due to stress, and limit cell overgrowth and cancers.”
Prior to the new study, researchers had only traced 20 of these genetic changes’ connections to aging, making it difficult to ascertain exactly how the remaining mutations affect lifespan. Klein reports that further analysis could point toward these genes’ influence on other animals’ aging processes, not just those of parrots and other feathered friends.
Whyte writes the scientists also found that parts of the blue-fronted parrot’s genome is responsible for regulating brain development function much like comparable genes in humans, offering a potential explanation for similarities between the two divergent species.
“These define how the brain grows and how many cells are built,” Mello says. “Humans ended up with bigger brains and more brain cells and more cognitive traits—including language—than primates. Parrots have bigger brains than other birds and more communication skills, and they have similar conserved elements that set them apart.”
The significance of these results, according to Genetic Engineering & Biotechnology News, is their potential for “uncovering the genetic basis of higher cognition.” Parrots are skilled at imitating sounds and engaging in complex social rituals—skills that at least partly stem from living in large communal environments—but researchers have yet to pinpoint the genetic roots of such evolved behaviors. As The New York Times’ Klein asks, did humans and parrots trace the same path toward advanced cognition, or did they follow different routes that produced similar results?
The answer to this question remains unclear, but the insights provided by the report, including the identification of a large suite of genes not previously associated with longevity and evident parallels between the evolution of human and parrot cognition, offer ample material for further study.