The fossil skeleton of a bird with strange teeth that lived 125 million
years ago has been discovered in China. The bird had bizarre ridges on
its teeth that may have enabled it to crack open hard-shelled insects
and snails, the researchers said.
The unusual fossil, described in the January issue of the Journal of
Vertebrate Paleontology, was so well preserved that some of its stomach contents were still present. The new find sheds light on the range of foods Earth's earliest birds ate during the dinosaur era.
"The teeth are weird and there are some stomach contents, which is
unusual," said paleontologist Gareth Dyke, of the University of South
Hampton in the U.K., who was not involved in the study. "It's more
evidence for the uniqueness and range of ecological specialization that
are seen in these particular Mesozoic birds."
Teeming with life
The new species' specimen was unearthed in the Liaoning province in China, where many fossils from the Cretaceous Period
(the period from 145 million to 65 million years ago that was the end
of the Mesozoic Era) have been found over the last 15 years, said study
author Luis Chiappe, director of the Dinosaur Institute at the Natural
History Museum of Los Angeles. The primeval forest was teeming with
ancient life, from pterodactyls and dinosaurs such as the microraptor to primitive lizards and various trees. The skies were also filled with birds, he said.
"This was clearly a hotspot of ancient bird biodiversity," Chiappe told LiveScience.
Toothy bird
The newly discovered bird, a robin-size creature called Sulcavis geeorum, lived between 121 million and 125 million years ago. Sulcavis geeorum belonged to a class of extinct toothed birds
called Enantiornithines, which were the most numerous birds during the
age of dinosaurs. The diminutive creature looked somewhat similar to
modern-day songbirds, with a key difference: the bird had some very
strange teeth. [Album: 25 Amazing Ancient Beasts]
The teeth of this tiny flier had sharp, pointy crowns. In addition, the
fossil found by Chiappe's team had preserved tooth enamel that formed
serrated ridges. Those serrated ridges probably enabled the birds to
crack open the hard exoskeletons of insects, crabs or snails, Chiappe
said.
The strange teeth may shed light on a prehistoric mystery of sorts: No
one knows exactly why early birds had teeth. It's also unclear why they
have lost their teeth at least four times since they first emerged in
the fossil record. In fact, modern-day birds still have genes for teeth, but the genes are turned off, Chiappe said.
"The traditional view is that teeth are heavy, and the birds evolved
beaks as a way of making their bodies lighter. These teeth are pretty
small and it's hard to imagine that they had such a huge impact on the
weight of the animal," he said.
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