More shared characters. . .
Birds show more specific similarities with certain groups of dinosaurs, notably the raptors:
- swiveling wrist joint with a crescent-shaped wrist bone (the semilunate carpal) on which the hand pivots
Birds, raptors, and carnosaurs (such as T. rex) all have shared features as well:
- a ěwishboneî (furcula)
- hollow bones with spaces for air sacs extending from respiratory system
- narrow, pointed claws