archaeopteryx

/ahr-kee-op-tuh-riks/US // ˌɑr kiˈɒp tə rɪks //UK // (ˌɑːkɪˈɒptərɪks) //

始祖鸟,古生物,古生物学家,古埃及人

Definitions

n.名词 noun

1
- : a reptilelike fossil bird of the genus Archaeopteryx, from the late Jurassic Period, having teeth and a long, feathered, vertebrate tail.

The only form referred to this subclass of extinct birds is Archaeopteryx, the earliest known bird.
The Ratitae differ from Archaeopteryx and the great majority of Carinatae in being flightless.
In Archaeopteryx however but five vertebrae take part in the formation of the sacrum.
In the wing of nearly all birds the ulna is thicker than the radius, but in Archaeopteryx the two bones are equal in size.
In Archaeopteryx all three bones of the pelvis are distinct, but they are imperfectly known.