Prehistoric animal discoveries are exciting ways to see what the world looked like when dinosaurs roamed the Earth, and they often show how much the world has evolved to this point. Per a new study published in the journal Current Biology, researchers just discovered that one animal that’s still on Earth today actually dates back over 120 million years: a peacock. The creature was the same size as a blue jay, but it had a tail that was twice the length of its body overall, prompting scientists to think that it would have trouble flying. Peacocks are known to use their large feathers to impress potential mates, so this animal was likely one of the first in history to do so.
The fossil of this animal, named Yuanchavis (a mythological bird), dates back to the early Cretaceous era in northeastern China. The body of the bird overall had short feathers at its base in addition to two long plumes, also called a pintail. These are even seen on modern-day birds, like sunbirds. “The long feathers were dominated by the central spine, called the rachis, and then plumed at the end,” said Dr. Jingmai O’Connor, a paleontologist at Chicago’s Field Museum in a media release. “Scientists call a trait like a big fancy tail an ‘honest signal’ because it is detrimental, so if an animal with it is able to survive with that handicap, that’s a sign that it’s really fit. A female bird would look at a male with goofily burdensome tail feathers and think, ‘Dang if he’s able to survive even with such a ridiculous tail, he must have really good genes.'”
This discovery also proves that birds are the animals that have survived the best through changes in Earth’s environments and conditions through centuries. “Understanding why living birds are the most successful group of vertebrates on land today is an extremely important evolutionary question because whatever it was that allowed them to be so successful probably also allowed them to survive a giant meteor hitting the planet when all other birds and dinosaurs went extinct,” Dr. O’Connor shared.
“This new discovery vividly demonstrates how the interplay between natural and sexual selections shaped birds’ tails from their earliest history. Yuanchuavis is the first documented occurrence of a pintail in Enantiornithes, the most successful group of Mesozoic birds,” said Dr. Wing Man, a researcher at the Chinese Academy of Sciences. “It is well known that sexual selection plays a central role in speciation and recognition in modern birds, attesting to the enormous extravagant feathers, ornaments, vocals, and dances. However, it is notoriously difficult to tell if a given fossilized structure is shaped by sexual selection, considering the imperfect nature of the fossil record. Therefore, the well-preserved tail feathers in this new fossil bird provide great new information about how sexual selection has shaped the avian tail from their earliest stage.”