Notochord, a flexible supporting rod along the back of an animal. It is present in all chordate animals at some stage in their development. A primitive chordate retains it throughout life. In higher vertebrate animals, the notochord is replaced before birth by a backbone.
Certain pet immunizations are mandatory in every state, but there are no universal laws governing travelling with pets. Take our quiz to learn more about pet travel laws.
Allosaurus was the most powerful, fearsome is and deadly dinosaur of the Late Jurassic. Until the Tyrannosaurus appeared this dinosaur was the largest predator to roam the Earth.