Mammal Like Reptiles Essay

The first mammals evolved from mammal-like reptiles at the end of the triassic period. Therapsids, or mammal-like reptiles, is an order of reptiles that lived in the Permian and Triassic Periods before going extinct in the mid Jurassic Period. It is difficult for scientist to determine when the divide between therapsids and mammals occurred. Early mammals had small, mouselike forms. Very few were large, because dinosaurs were the unquestioned dominant land animals on earth. The ecological niche they inhabited included eating plants, insects, and small lizards. They lived in trees and hunted at night to avoid dinosaurs, who hunted in the daytime. They walked on four legs like mice. These mammals had the characteristics of all mammals, such as being warm blooded and females producing milk for their young. The first mammals evolved from mammal-like reptiles at the end of the triassic period. Therapsids, or mammal-like reptiles, is an order of reptiles that lived in the Permian and Triassic Periods before going extinct in the mid Jurassic Period. It is difficult for scientist to …show more content…
Great Apes diverged from Lesser Apes about 20 million years ago. Apes have unique characteristics that separate them from monkey, the most obvious one being the lack of a tail. They also have an appendix, a wide and shallow chest, a shoulder structure that allows the arm to rotate freely, and the most complex brain among primates. They are usually larger with a more upright posture that allows some of them them to walk on two legs. It is the ball and socket joint in their shoulder that allows apes and monkeys to swing in trees. Great apes are more intelligent with the ability to use tools, use language, and have complex social lives. The oldest known great apes is the Pierolapithecus catalaunicus, which lived 12 million years ago. It was 77 pounds, ate berries, and may have stood