The rare 3D fossil of Ichthyornis
dispar, which lived in North America around 86 million years ago, reveals that the first bird beaks had teeth.
<B The fossil of the Ichthyornis
dispar and an artist's impression of the seagull-sized bird
Ichthyornis dispar was a toothed bird that lived in the Late Cretaceous, about 100 million years ago, in present-day North America.
The paper authored by Bhullar and his colleagues was based on the study of new specimens of Ichthyornis dispar, which included a complete skull of the primitive bird, as well as two pieces of the cranium that had been previously overlooked from the existing collection of fragments, discovered in the 1870s.
There are also some extremely rare bird fossils including a skeleton of an ichthyornis
and one with its feathers still on.
Eighty million years ago, Ichthyornis
lacks the toothless bill on the lower jaw and part of the upper, although there is one on the front of the upper jaw.
The next chapter (The Cretaceous-Divers and Seabirds) covers not only the extinct diver Hesperornis and seabird Ichthyornis
and closest of kin from the Cretaceous, but also includes a curious pastiche of topics from enantiornithine land birds to DNA-DNA hybridization.
-- Four avian fossils from the Cretaceous of Texas are referred to Ichthyornis
. Two specimens identified as I.
no longer gets stuck in corners of underwater bases.
The sequence of these modifications has remained elusive because Late Cretaceous bird fossils, such as Hesperornis and Ichthyornis
, already possess a reduced tail (Marsh 1880).
New Dino: Ichthyornis
- A fish-eating seagull that likes to ride on its owner's shoulder.