(PhysOrg.com) -- During a presentation at the Society of Vertebrate Paleontology's 71st annual Meeting in Las Vegas, researchers Gareth Dyke and Darren Naish from the University of Southampton presented their findings of the first known Mesozoic bird colony remains.
The discovery was made in the Sebes area of Transylvania, Romania and includes a large collection of bird fossils and eggs, both partial and whole, trapped within the limestone. It is believed that this colony of birds was wiped out when a flash flood hit the area some 100 million years ago.
The prehistoric birds belonged to the enantiornithines and had claws and saw-like beaks with teeth. They had clawed fingers on their wings but, besides these features, these birds resembled modern day birds. These birds are an extinct branch of modern birds but researchers have been unable to determine why these became extinct while other ancestors lived for much longer.
This is the first evidence that ancient birds nested near the water similar to how ducks do now. It is also the first time full, well-preserved eggs have been found and researchers hope this will help them learn about the biology of these animals. Finding whole and preserved eggs, researchers say this will allow them to figure out the size and the volume of the birds eggs for the first time.
The location where this fossilized nesting ground was discovered has been rich in other remains as well. Researchers have also discovered the remains of a predatory bird-like dinosaur known as a Balaur, small rodent animals, a dwarf plant-eating dinosaur and one of the worlds largest pterosaurs. Back during the Cretaceous period, Romania was a large island and apparently filled with many different species of animals. One thing the researchers do note is that to date, there doesn't seem to be any evidence of the big predatory type dinosaurs in this area.
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