From The Conversation (2/4/24)…
After 10 years of work, landmark study reveals new ‘tree of life’ for all birds living today
The largest-ever study of bird genomes has produced a remarkably clear picture of the bird family tree. Published in the journal Nature today, our study shows that most of the modern groups of birds first appeared within 5 million years after the extinction of the dinosaurs.
Birds are a large part of our lives, a sign of nature even in cities. They are popular among the general public and well studied by scientists. But placing all of these birds into a family tree has been frustratingly difficult.
By analysing the genomes of more than 360 bird species, our study has identified the fundamental relationships among the major groups of living birds.
The new family tree overturns some previous ideas about bird relationships, while also revealing some new groupings.
Resolving a messy relationship
Previous studies showed the bird family tree has three major branches. The first branch contains the tinamous and ratites, which include flightless birds such as the emu, kiwi and ostrich.
The second branch holds the landfowl and waterfowl – chickens, ducks and so on. All other birds sit on the third branch, known as the Neoaves, which include 95% of bird species.
The Neoaves branch includes ten groups of birds. Most of these are what biologists have named the “Magnificent Seven”: landbirds, waterbirds, tropicbirds, cuckoos, nightjars, doves and flamingos. The other three groups are known as the “orphans” and include the shorebirds, cranes and hoatzin, a species from South America.
The relationships among these ten groups, especially the orphans, have been incredibly difficult to resolve. Our genome study shows a resolution is within reach.
