A Prehistoric Puzzle We’re Still Trying To Solve Is The Mysterious Origin Of Feathers
Birds and feathers are strictly associated with each other. Feathers allow the winged creatures to fly, stay warm, and put on dramatic displays come mating season. However, birds were actually not the first to have feathers. The original trendsetters are extinct dinosaurs.
Scientists have been piecing together this prehistoric puzzle, uncovering when feathers evolved and which animals sported them.
The first fossilized feathers were found in extinct dinosaurs in the 1990s, but there are still many unanswered questions about these distinctive features.
“While dozens of feathered dinosaurs have been identified since Sinosauropteryx was first unveiled in the 1990s, they’re mainly meat-eaters that are close relatives of birds,” said Paul Barrett, a co-author of the study.
“Everyone agrees that these dinosaurs had feathers, but there’s little consensus beyond that.”
More fossils need to be discovered and analyzed to reveal whether feathers came from a common ancestor or if the trait evolved multiple times in a group. Currently, scientists are divided over when feathers evolved.
One theory of feather evolution suggests that feathers first evolved in a common ancestor of dinosaurs/birds and pterosaurs.
That means both groups would have inherited their plumage. Later, some would have lost their ability to grow feathers, which explains why there are scaly species.
Other researchers believe that feathers developed at a different time. They think that feathers might have evolved among the ancestors of dinosaurs, but the fuzzy features of pterosaurs are completely separate.
Sign up for Chip Chick’s newsletter and get stories like this delivered to your inbox.
The reason why different theories have emerged is that most feathered dinosaur fossils come from the Cretaceous Period, long after feathers first evolved.
“We need to find new sites with fossilized feathers, particularly from the Jurassic and the Triassic,” Barrett said.
“The Triassic is especially important, as finding feathered dinosaurs at this early time in dinosaur evolution would suggest that all dinosaurs had an ancestor with feathers.”
“If feathered dinosaurs aren’t found among early dinosaurs, then it makes it more likely feathers were an innovation among later groups.”
Aside from hunting for more fossils, researchers will need to settle on an exact definition of a dinosaur feather. They will have to analyze its structure, chemical composition, and if it grows out of a follicle in the skin. Preserved ancient skin will be very helpful for this research work.
When comparing the fossilized skin of some dinosaurs and early birds from China, it appeared that they had similar tissues, which supports the idea that feathers came from a common ancestor.
However, other dinosaurs had more reptile-like skin or a mix of feathers and scales, so it’s possible that feathers evolved independently.
At the end of the day, there is still much more work that needs to be done in order to confirm the origin of feathers.
The study was published in Biology Letters.
More About:News