Like dinosaurs, crocodilians evolved from a meat-eating land ancestor that could breathe as it ran.
Crocodilians are an ancient, diverse group. The earliest crocodilian was a small land reptile. Some later crocs became amphibious, or even fully aquatic.
One 50-foot-long croc with teeth like those of its contemporary, Tyrannosaurus rex, preyed upon dinosaurs. Another crocodilian had a tailfin and limb-paddles, and swam the seas with ichthyosaurs and plesiosaurs.
crocodilians (crok-a-DILL-ee-uns): the living reptiles most closely related to birds and extinct dinosaurs; crocodiles, alligators, caimans, and the gharial.
New feature:
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tail surrounded by large, bony plates embedded in skin skull table: broad, flat area of skull behind eyes
An Expectant Mom
A crocodilian mother-to-be watches, waits, and listens for signs of new life. Her babies will chirp as they hatch -- a signal for her to dig them out.
Parenting in Dinosaur Relatives
Crocodilians are closely related to dinosaurs, extinct and living (birds). Like dinosaurs crocodilian mothers build nests and care for their offspring. Mama crocodiles guard their eggs and young carefully, and communicate with them by calls.
PICTURE CAPTIONS:
- Terrestrisuchus, a small land crocodilian
- Meteriorhynchus, a fully aquatic crocodilian
- Deinosuchus, a 50-foot-long crocodilian