A macaw named Poncho starred in movies like “102 Dalmatians,” “Dr. Doolittle” and “Ace Ventura: Pet Detective” before retiring in England. She recently celebrated her 90th birthday.

Alex, an African grey parrot who lived to 31, knew colors, shapes and numbers, and communicated using basic expressions. He could do what toddlers only do after a certain stage of development — know when something is hidden from view.

And they’re just two of the many parrots in the world who have surprised us with their intelligence, skills and longevity.

“Nature does these experiments for us, and then we have to go and ask, how did this happen?” said Dr. Claudio Mello, a neuroscientist at Oregon Health and Science University.

So he and a team of nearly two dozen scientists looked for clues in the genome of the blue-fronted Amazon parrot in Brazil, his home country.

After comparing its genome with those of dozens of other birds, the researchers’ findings suggest that evolution may have made parrots something like the humans of the avian world.

In some ways, the long-lived feathered friends are as genetically different from other birds as humans are from other primates. Their analysis, published Thursday in Current Biology, also highlights how two very different animals — parrots and humans — can wind up finding similar solutions to problems through evolution.

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A general rule of life span in birds and other animals is the bigger or heavier you are, the longer you live. A small bird like a finch may live five to eight years, while bigger ones like eagles or cranes can live decades. The blue-fronted Amazon and some other parrots are even more exceptional, in that they can live up to 66 years — in some cases outliving their human companions.

In their analysis, Dr. Mello and his colleagues found that these parrots and some other long-lived birds shared changes in a set of 344 genes that seem to be involved in various processes that influence life span, like how an animal’s body repairs DNA, manages cancer or controls cell growth.

While about 20 of these genetic changes have been implicated in aging in other animals, the rest of the genes’ direct role in life span has not been investigated. Future studies may reveal that they’re not just important to aging in parrots or other long-lived birds, but in other animals as well.

Parrots are distinguished not only by their longevity, but also by their cognitive abilities.

“They’re really, really smart animals, and the brains are particularly big. We seem to see a parallel in humans that have bigger brains and enhanced capacities, compared to other animals,” he said. “We think parrots are the parallel in the avian world.”

The team found changes in parts of the parrot genome remarkably similar to those that set humans apart from other primates.

This intrigued Dr. Mello. The similar changes found in parrots and humans aren’t to the genes themselves, but occur along regions of the genome that regulate the expression of nearby genes that seem to play a role in brain development and intelligence.

Could these changes explain the parrot’s large, complex brain and diverse set of talents?

Only by looking at specifics can we find out. While it’s relatively simpler to quantify age and see how various genetic changes might alter it, it’s harder to assess how tiny switches turning on and off at certain times might alter the size of a parrot’s brain — or how well it can impersonate Matthew McConaughey.

By looking at specifics in the genetic changes of parrots and humans, researchers in the future may develop a better understanding of the powers of convergent evolution.

Perhaps there is only one path that leads complex brain structures and advanced cognitive abilities like those of parrots and humans. Or it could be that there is more than one evolutionary route capable of producing such complex creatures in different parts of the animal kingdom.



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