Chickens are some of the closest dino relatives
SYDNEY — Last week, scientists published a new bird “family tree” based on an extensive genetic analysis of dozens of species. “On the new tree, ostriches and tinamous perch on the most ancient branch and then come chickens, turkeys and ducks,” Susan Milius noted in her Science News story about the discovery. By one measure — overall chromosome pattern —chickens are even more similar to dinosaurs than any other bird species in the analysis.
That news wasn’t too surprising to my host here in Australia: Carolynn “K-lynn” Smith, an animal behavior scientist at Macquarie University who spent several years studying how chickens interact and communicate with each other. She says that there were times when watching the birds hunt little lizards was “like watching Jurassic Park.”
That’s hard to imagine when watching the two ex-research chickens now living in Smith’s backyard. Truly domesticated, they will run up to the back door and beg for a meal if they see someone inside. And they spend most of their days scouring the yard for insects to eat. These birds would seem to be as far from a T. rex as possible.
That is, until you start looking more closely. First you notice the scaly, lizardlike skin on their legs and feet. Then there are the eyes that are always on the lookout for both a potential meal and a potential predator. (Want to know what the warning call for a ground predator sounds like? Accidentally let the cat out of the house and you’ll find out pretty fast.) All they seem to be missing are teeth, fingers and a real tail (instead of their all-feather ones).
The similarities between chickens and dinosaurs have fascinated scientists for a long time and have resulted in some interesting endeavors. For instance, researchers recently used chickens to study how a T. rex may have moved. They raised chickens to which they had strapped plungerlike prosthetic tails and filmed how the adult birds strutted. To accommodate the appendage, the chickens shifted their weight forward and moved in a less birdlike way.
And then there’s famed paleontologist Jack Horner’s plan to create a “chickenosaurus.” Several years ago, Horner proposed creating a velociraptor-like dino by adding teeth and a tail to a chicken and changing its wings into fingers and claws. But instead of gluing together the pieces to create a taxidermied nightmare, Horner is actually working with molecular biologists to tinker with the chicken’s DNA. Matthew Harris at Harvard Medical School, for instance, has created toothed chicken embryos, though the teeth lack hard enamel. The bones for hands are already buried beneath the bird’s feathers. And Horner’s team has been working hard on finding the genes that control tail growth. Birds grow tails as embryos but absorb them before they are born; finding out how to stop that resorption could result in tailed birds.
Chickenosaurus could be real within a decade, Horner has said. And that could mean there could one day be something even more dinolike pecking away in my friend’s backyard. But I wonder whether the eggs would taste as good?