Chicken-sized Dinosaurs Added to Raptor Family Tree
Two new species of raptor dinosaurs were discovered last week from a site in Mongolia.
The first of these, “Halszkaraptor”, was described in the journal “Nature” and has been described in the media as a raptor dinosaur with similarities to swans, geese, and penguins. While that description is illustrative, the details of the features of this animal deserve closer examination.
About the size of a chicken, “Halszkaraptor” is not a large dinosaur. It had a small head and a long slender neck. It did not have beak. Instead, its mouth bristled with over 100 small pointed teeth. Its snout also appears to have been sensitive, like that of a crocodile, possibly to detect prey underwater. It would have had feathers, but is not thought to have flown. Instead, its short forelimbs, including a very long third finger, look a lot like the “paddles” of some fossil swimming reptiles, so it may have used its arms to swim like a penguin today. However, its feet looked much more like those of a “Velociraptor”, including a wickedly-curved enlarged claw on each foot.
These features show a dinosaur with unique evolutionary adaptations not seen in non-bird dinosaurs until now. It is a very odd and exciting discovery.
Later in the week, a close relative of “Halszkaraptor” was described in the journal “American Museum Novitates.” Called “Almas”, a reference to the Mongolian yeti, this dinosaur is more closely related to dinosaurs like “Troodon” that appear as the Philip J. Currie Dinosaur Museum’s logo. While similar to its close relatives, it was found to be a distinct species based on several features, including a short skull and fewer teeth.
Interestingly, “Almas” is also associated with eggshell fragments. While similar in size to “Halszkaraptor”, “Almas” is too large to be a hatchling. It may have been protecting or brooding the eggs.
Small dinosaurs are a rare part of the fossil record, so adding these two dinosaurs from Mongolia in the same week is quite exceptional. The rate of dinosaur discovery in the world is not slowing down, and palaeontologists are always continuing to hunt for the next find.