Primates

FINAL REVIEW Primates- The order of mammals that has a complex of characteristics related to an intial adaptaion to life in the trees. Suborders- prosimii/ anthrop idea/ prosimians/ anthropoids Primate characteristics- an arboreal(tree living) enviornment -3 dimension living length, witdth, height -grasping hands(prehensible) -binuclear stereoscopic vision (able to perceive depth) Primate social structure- one male/ one female, one male/ multifamily, one female/ multi male, multi male/ multi female Primate social structure and sexual dimorphism- Dominance hierarchy: which individuals are dominant in social behaviors ruled by those with greatest access to food or sex. Sexual dimorphism: the average difference in body size between adult mates and adult females for primates adult males will be much larger than females. Prosimians- “before simians” before monkeys or apes biologically primitive Characterisitcs: lack color vision, some have single claw on each hand or foot, many are nocturnal Plurnal- active during the day Loris- nocturnal prosimian found in Asia and Africa Tarsier- nocturnal found in Indonesia Lemur- today in Madagascar Dental Formula: New world monkey- 2-1-3-3 (more pre molars) Old world monkey: 2-1-2-3 Relative Dating Methods: Biostratigraphy: in which sites can be assigned an approx. age based on the similarity of animal remains to those from other dated sites. Paleomagnetic roversals: method of dating sites based on the fact that the earth’s magnetic field has switched back and fourth, North-South Stratigraphy: older remains are found deeper in the earth because of cumulative build up of earth’s surface overtime Molecular Dating: method of genetic analysis to estimated the sequence in timing of divergent evolutionary lines Chronometric Dating Methods: Carbon 14 Dating: a chronometric dating method based on the half life of carbon 14 that can be applied to organic remains such as charcoal dating back over the past 50,000 years or so. Dendrochronology: A chronic dating method based on the fact that trees and dry climates tend to accumulate one growth ring per year. The width of the rings very according to climate, and a sample can be compared to a master chart of tree rings over the past 10,000 years. Potassium-Argon: based on the half life of radioactive potassium (which decays into argon gas) that can be used to date volcanic rock older than 100,000 years. Bipedalism- moving about on 2 legs, characterized by a striding motion Hominids- family within the hominoids, including humans and great apes (orangutans, gorillas, chimpanzees and bonobos) Hominin: Humans and their ancestors since the time of divergence from the common ancestor of humans chimpanzees or bonobos. Hominoid: A super family of anthropoids consisting of apes and humans, hominoids have a shoulder structure adapted for climbing and hanging, lack a tail, are generally larger than monkeys and have the largest brain to body size ratio among primates Ardipithecus Ramidus: An early primitive hominid species from Africa dating between 5.8 million and 4.4 million years ago Australopthecines robust: A species of robust austral pith dating between 2 million and 1.4 million years ago and found in South Africa Australopthecines gracile: An early hominin (human) dating to 2.5 million years ago in East Africa, it differs from other austral piths in having large front and back teeth. Although, the back teeth are not specialized to the same extent as found in the robust. Epidemic: A pattern of disease rate when new cases of a disease spread rapidly throughout a population. Endemic: A pattern of disease rate when new cases of a disease occur at a relatively constant but low rate overtime. Epidemiological transition: The increase in life expectancy and the shift from infectious to noninfectious disease as the primary cause of death. Paleopathology: The study of disease and prehistoric populations, based on analysis of skeletal remains and archeological evidence. Pandemic: A widespread of epidemic that effects a large geographic area such as a continent. Brachiation: A method of movment that uses the arms to swing from branch to branch (gibbons) Genus Homo Habilis: 2.0 million years ago-1.5 million years ago, Africa, first stone tools. Homo Erectus: 2.0 million years ago- 27 ka, modern post cranial anatomy, avg cranial capacity 930 cc, first use of fire, first use of hunting, acheulian hand axe. Homo Neandertal: 200,000-28,000 bp, Europe Asia and Middle East. Great Apes: Old world monkeys Hominid Evolution 6ma-15ka There are certain things that distinguish humans from apes and other animals. One thing is that fact that humans are bipedal, meaning we walk on two legs. Another thing is the reduction in size human canines and other teeth. Tools were a factor in reduced tooth size. Also, since processed foods have been developed tooth size in humans has decreased greatly. One thing that distinguishes us from other animals is our large brain size. Humans have very large brain sizes compared to their bodies; human brains are especially large in the prefrontal cortex. Two major things that distinguish us from other animals are language and culture. There are many proofs of how humans evolved. One is the fossil record. The fossil record is a compilation of fossils that have been found. Not all fossils have been found. The fossils that have been found have become more complex and human like as the get nearer to our time. One of our earliest human ancestors is thought to be the Australopithecus afarensis. One very complete fossil of this was found and it was named Lucy. Another proof of human evolution is the arch record. This is an assemblage of artifacts found around humans. These are mostly tools and animal bones. The tools become more advanced as the fossil record moves on. Australopithecus afarensis is thought to be one of the oldest direct relatives of us. They were about three to four feet tall and very ape like. Homo habilis is thought to be a more closely related relative. Homo erectus is another hominid in our lineage. Homo erectus were bipedal. Human evolution is a very complicated thing. There is still much more to be learned about evolution. Although the fossil records are nowhere near completed. the great amount of data, the comparison of us and other similar organisms, and the way humans will continue to evolve are all reasons that I believe in human evolution. Human evolution has many different theories. The one that you accept is up to you.