Canadian researchers say they've narrowed down the likely owner of a
dinosaur nest, abandoned on a river's edge 77 million years ago, adding
the discovery offers a unique look at dinosaur reproduction and the
evolution of birds. Scientists from the University of Calgary and Alberta's
Royal Tyrrell Museum say the nest unearthed in northern Montana in the 1990s
likely belonged to one of two types of small, carnivorous dinosaurs. The two
suspects are a ceanagnathid, which looks somewhat like an ostrich, or a small
raptor called a dromaeosaurid. Both are small by dinosaur standards and
related to modern birds. The nest likely held up to a dozen eggs, of which
only fossilized fragments remain. "We think, based on characteristics of the
eggs, that we are probably dealing with a nest from a small raptor but we
can't (be) 100 percent sure and rule out the other one," said Francois
Therrien, curator of dinosaur palaeoecology at the Royal Tyrrell and
co-investigator. Nests from meat-eating dinosaurs are extremely rare.
Only one other example has been found in North America, a nest of
67-million-year-old Troodon eggs that was also unearthed in Montana.
Therrien said the latest nest was discovered by commercial fossil hunters and
originally thought to be from a relatively common duck-billed hadrosaur.
Darla Zelenitsky, a University of Calgary paleontologist, realized that the
nest, a raised mound 50 cm (20 inches) across and surrounded by eggs, was
actually from a small meat-eater. Zelenitsky is the lead author of a paper
on the nest, published on Thursday in the journal Paleontology. Therrien said
dinosaur nest, abandoned on a river's edge 77 million years ago, adding
the discovery offers a unique look at dinosaur reproduction and the
evolution of birds. Scientists from the University of Calgary and Alberta's
Royal Tyrrell Museum say the nest unearthed in northern Montana in the 1990s
likely belonged to one of two types of small, carnivorous dinosaurs. The two
suspects are a ceanagnathid, which looks somewhat like an ostrich, or a small
raptor called a dromaeosaurid. Both are small by dinosaur standards and
related to modern birds. The nest likely held up to a dozen eggs, of which
only fossilized fragments remain. "We think, based on characteristics of the
eggs, that we are probably dealing with a nest from a small raptor but we
can't (be) 100 percent sure and rule out the other one," said Francois
Therrien, curator of dinosaur palaeoecology at the Royal Tyrrell and
co-investigator. Nests from meat-eating dinosaurs are extremely rare.
Only one other example has been found in North America, a nest of
67-million-year-old Troodon eggs that was also unearthed in Montana.
Therrien said the latest nest was discovered by commercial fossil hunters and
originally thought to be from a relatively common duck-billed hadrosaur.
Darla Zelenitsky, a University of Calgary paleontologist, realized that the
nest, a raised mound 50 cm (20 inches) across and surrounded by eggs, was
actually from a small meat-eater. Zelenitsky is the lead author of a paper
on the nest, published on Thursday in the journal Paleontology. Therrien said
