Archaeopteryx. Computer enhanced image of a fossilised skeleton of Archaeopteryx,a reptile- like bird which is the ancestor of modern birds. Archaeopteryx lived about 150 million years ago during the Jurassic period and was about the size of a large crow. This bird had many reptilian features,having probably evolved from small therapod dinosaurs. Unlike modern birds,Archae- opteryx had teeth,clawed hands,a bony tail and lacked air pockets in its bones. Its breast bone (sternum) also lacks the carinate "keel" to which modern birds anchor their powerful flight muscles. Archaeopteryx's feathers were asymmetrical like a modern bird's,but it was probably a weak flyer | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Kulyk, Mehau |
Bildgröße: | 3635 px × 2512 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |