Characteristics of Hominidae
Characteristics of hominidae are bipedal mammals with a large brain and opposable thumbs. They are herbivorous, but some species also eat meat. Hominids have a complex physiology, with organs such as the lungs and heart in the torso, and a stomach and legs.
Hominins have evolved several adaptations, including walking and running. The human walking gait, which is unique among primates, is believed to have evolved over a period of thousands of years. It has been found to be slightly more energy efficient than the walking of chimpanzees. This is attributed to the fact that the human upright posture puts the majority of ground reaction forces at the hip and knee, reducing the energy required by the hip muscles.
The Hominoidea family includes both extinct and modern great apes. In Africa, humans and other great apes first evolved. Early human fossils came from Africa. The term “hominid” evolved gradually, and today’s usage of the term refers to all great apes, including humans.
The placentae of the nonprimates differ significantly from those of the hominoids. In nonprimates, the placenta has small, hollow spaces, which allow maternal blood to circulate. In anthropoids, the maternal blood is stored in a large compartment. The free tips of the chorion protrusions intrude into the large compartment, which exposes them to the maternal bloodstream.