Evolutionary anthropology is the study of the relation between social behavior and the evolution of hominids and non-hominid primates. It includes:

• The anthropology of human evolution.
• The sociocultural evolution of human behavior.
• The archaeological study of human technology and change over time and space.
• Studies of human genetics and changes in the human genome over time.

Evolutionary anthropology is concerned with both biological and cultural evolution of humans, past and present. It is generally based on a scientific approach, and brings together fields such as archaeology, behavioral ecology, psychology, primatology, and genetics. It is a dynamic and interdiscplinary field, drawing on many lines of evidence to understand the human experience, past and present.

Studies of biological evolution generally concern the evolution of the human form. Cultural evolution involves the study of cultural change over time and space and frequently incorporate Cultural transmission models. Note that cultural evolution is not the same as biological evolution, and that human culture involves the transmission of cultural information, which behaves in ways quite distinct from human biology and genetics. The study of cultural change is increasingly performed through cladistics and genetic models.

The Evolution of Hominins

Both mammals and dinosaurs evolved from reptiles. Yet, at the start of the Mesozoic age, 65-250 mya, it was Dinosaurs, not mammals, that ruled. Dinosaurs had taken advantage of all the open niches, (Ecological niche) and had diversified, while mammals stayed small. It wasn’t until the Cretaceous–Tertiary extinction event, where many niches opened up, that mammals were able to diversify. It was during this time, (Paleocene) in which the plesiadapiformes evolved. Plesiadapiforms are the proposed earliest precursor to primates. These then evolved into the first real primate; the prosimian. Prosimians are small, primitive primates that still exist today. The Oligocene prosimian was an early anthropoid.

Anthropoid is a sub-group of primates including monkeys, apes and hominoids.

Anthropoids broke off into platyrrhines (New World monkey) and catharhines (Old world monkeys, apes and hominoids).

Catharhines broke off into Cercepithoids (Old world monkeys) and hominans (line of primates that leads to humans).

Paleoanthropology is the study of the early hominan (see Hominid).

Characteristics of Hominins include Bipedalism and Canine reduction. Apes, our most recent primate ancestor, are quadrupeds (Quadrupedalism), so their center of gravity is evenly distributed on all four limbs. In Hominids, the center of gravity is above the legs. When looking at paleospecies [1] of primates, one can tell if they were Hominid simply by looking at the Foramen Magnum. On quadrupeds, like apes, the Foramen Magnum is to the back of the skull, while in bipedal organisms, like hominids, the Foramen Magnum is further underneath the skull, showing that the head was held upright above the body and center of gravity.

Canine reduction simply means that teeth in hominids are greatly reduced in size compared with those of apes.

Some more important differences between hominids and apes include differences in the spine, pelvis, femur, and feet.

In hominids, there are wedge shaped vertebrate to make the spine more curved. This is naturally selected for bipedal organisms because the curves allow for more balance.

Also in hominids, the pelvis is shorter and broader than in apes. This is because the internal organs of bipedal organisms rest within the pelvis, where in quadrupeds the organs just hang. The result of a shorter and broader pelvis also affects the size of the butt. Because of the different shape of the pelvis, the Gluteus maximus muscle also has differences. In apes the Gluteus maximus pulls the thighs to the side, whereas in hominids the Gluteus maximus is behind the hip and pulls the thighs backwards to keep bipedal organisms from falling forwards. This makes the Gluteus maximus muscle very strong and much bigger in hominids than in apes.

Apes typically have flat feet, and their toes are all around the same size. In hominids, the big toe is enlarged and is brought to line with the other toes. The foot also has an arch. This arch absorbs the shock that walking on two feet gives. Without it too much pressure is put on the legs.

As bipedal organisms, hominids evolved traits that helped it to stand upright. Still, some traits come from acting it out. Walking on two legs causes an organism to develop angled femurs. When angled the Femur helps to maintain balance over one foot when walking. Non-hominids, if trying to walk Bipedally, have to throw their legs forward and they end up walking with a swinging motion.

[edit] See also

• Hypergamy

[edit] External links

• Evolutionary Anthropology Society
• Max Planck Institute for Evolutionary Anthropology
• Evolutionary Anthropology - a journal

Ciochon, Russell L., Robert Jurmain, Lynn Kilgore, and Wenda Trevathan. Introduction to Physical Anthropology 2009-2010 Edition. Belmont, CA: Wadsworth Publishing, 2009. Print.

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