Masiakasaurus (mah-shee-kah-sore-us) was one of Madagascar's unique dinosaurs. Like today Madagascar was separate from Africa 70 million years ago, allowing dinosaurs not found anywhere else to evolve away from their prehistoric cousins. Masiakasaurus was one of them, evolving away from the line that will soon become tyrannosaurus rex, Masiakasaurus like the T. rex was a theropod (two legged dinosaurs) that had strange features like proto feathers and two sets of teeth.
Unlike any dinosaur ever discovered before, Masiakasaurus' front teeth protruded outwards from the jaw instead of pointing upwards like other predatory dinosaurs. The front teeth were used to catch and hold fish then Masiakasaurus would have tilted its head back to throw the fish back in its mouth where the second set of teeth came in. The second set of teeth were a little like sharks teeth only smaller and rounder, these teeth were serrated (like chainsaw teeth) so that the dinosaur could rip the fish into bite-size chunks before swallowing.
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Cynodont (sigh-no-dont) was the ancestor of the mammals, though not yet a true mammal, it was a mammal-like reptile. Mammals did in fact live during the dinosaurs but they were not that big, sizes ranged from as small as a paperclip to the size of a house cat. Cynodont was about as big as a large rat (1 - 1.5m).
Like today's mammals Cynodonts' cared for their young, both parents shared the responsibility of caring and protecting the pups. Unlike today's mammals Cynodonts' layd eggs (like the platypus), when they hatched the mother would stay in the den to feed them milk and protect them while the father went out hunting or cleaned the nest.