2 Human EvolutionDescribe the major anatomical features that define humans as primatesPrimata = an order of mammals, including apes, monkeys, tarsiers and lemurs
3 Humans and PrimatesHumans share the following characteristics with other Primates:grasping limbs, with long fingers and a separated opposable thumb;mobile arms, with shoulder joints allowing movement in three planes and the bones of the shoulder girdle allowing weight to be transferred via the arms;stereoscopic vision, with forward facing eyes on a flattened face, giving overlapping fields of view;skull modified for upright posture;**Primates share a common ancestry
5 Hominids originated in Africa and spread to other continents 2. Outline the trends illustrated by the fossils of Ardipithecus ramidus, Australopithecus, including A. afarensis and A. africanus, and Homo, including H. habilis, H. erectus, H. neanderthalensis and H. sapiens.Hominids originated in Africa and spread to other continentsArdipithecus fossils found in EthiopiaAustralopithecus and Homo habilis fossils found in Southern and Eastern AfricaHomo erectus fossils found in Eastern Africa and in AsiaHomo neanderthalensis fossils found in EuropeHomo sapiens fossils found in all continents except Antarctica
7 Ardipithecus ramidus Oldest hominid (4.4 million years ago) more primitive (ape-like)Bipedialism?Low foreheadSmall craniumProtruding brow and jawBig teeth
8 Australopithecus afarensis 3.9 million years“Lucy” (Fossil found 1978)a low forehead bony ridge over the eyesa flat nose and no chin more humanlike teeth, (large cheek teeth – large chewing muscles)and the pelvis and leg bones resembled those of modern man. Females were smaller than males.
9 Australopithecus africanus million years agoappeared to be apelikeLight build; probably relatively long arms; more "human" featuresHigher forehead; shorter face; brow ridges less prominentprotruding facesmall brain,distinctly unapelike dentition including small canines and large, flat molars. (large cheek teeth – large chewing muscles)A bipedal posture was again indicated by the central position of the foramen magnum, and by the anatomy of the spine, pelvis, and femur.
10 Homo habilis Approx. 2.5 million years First definite human ancestor 1st member of genus homoLarger brainPresence of tools (indicates brain capable of complex thought)Bi-pedal foot structure
11 Homo erectus 400, 000 y – 1.6 million years ago Larger brain capacity Reduced size of face and cheek teethThicker cranial bonesBone limbs show little change
12 H. neanderthalensis 30, 000- 200, 000 years ago similar to homo sapiensFeatures related to cold climate adaptationBroad bone and muscle structureShort, strong bodyLarge, rounded nasal openingBelieved to be a genetical variant of H. sapien
13 H. sapien (archaic) 500 000 – 200 000 years ago Skull became more rounded than H. erectusTeeth are less thick and denseBrow bridge still prominentMuch steeper forehead development of forebrain, planning, reasoning, speech.Evidence of more complex tools
14 H. sapiens-modern man 1500-1600 years highly developed brain and thus, mental capacitysocial capabilitiesless hairless brow ridge,jaw has decreased in size
16 Family Hominidae – determined by bipedialism Trends in hominid evolution:increasing adaptation to bipedalism, especially forward movement of foramen magnumincreasing brain size in relation to body sizedecreasing relative size of: face, jaw, teeth, esp. canines; increasing relative size of brain case, forehead