11 10 2015 November 3 2015 Rise of the Genus Homo The Genus homo genus homo The current hypothesis is that A Africanus is the step right before Africanus Sediba best candidate Homo habilis H Erectus Smaller flatter face Larger head larger brain size Hallmark of Homo Brain Size o Reorganization and expansion of the human brain Expansion not as dramatic in the beginning as we previously though Mosaic evolution Mosaic evolution or modular evolution is the concept that evolutionary change takes place in some body parts or systems without simultaneous changes in other parts Another definition is the evolution of characters at various rates both within and between species prognathic your teeth are Smaller flatter face Reduction in size of dentition parabolic shape changes how Scavenging and tool making Obligate bipeds What is a stone tool Cutting edge breakage patterns How were the made o Percussion method direct percussion rock on rock o Pressure flaking newest one Stone tool technology were made sharp edges o Modern flint knappers o experimental archeology reconstruction of how stone tools when struck properly stone fractures in a controlled way to produce blank leftover rock What are they used for Use wear analysis o Skinning animals o Removing meat marrow o Digging First stone tool industry Oldtown tools 2 6 Ma Tanzania Ethiopia Goma Odiuval Gorge one of the first sites they found tools also Lower Paleolithic Hammer stones cores flakes Africa Rep of Georgia Australopithecines Increased protein consumption possibly linked to brain increase Brain Structure and Diet Oldwan Tool industry o Primarily vegetarian o Relied on skull teeth Homo o Omnivores o Relied on tools Meat in diet Homo Habilis twiggie boisei 2 0 1 4 Ma Olduvai Gorge Tanzania Large brain biped Reduced Facial size Parabolic palate small teeth Tools australopithecus habilis o TOO primitive Chimpanzees Homo habilis modern human Homo possibly lived contemporaneously with australopith species for 1 million years Taxonomic difficulties Male female 2 different species o KNM ER 1470 752 cc Big brain primitive face o KNM ER 1813 510 cc 1 8 Ma homo rudolfensis If they re different species Small brain derived face 1 9 Ma homo habilis if they re same species Would have more sexual dimorphism than a modern day gorilla Similarities shared derived characteristics x differences Lumpers vs splitters Cradle of humankind Homo Naledi Rising star is 800 m from Swartkrans Definitely sexual dimorphism CC 465 female 560 male Closest to H erectus but no sagittal keeling not a long low vault 6 cranial pieces teeth o smaller anterior teeth than Australopithecus like homo o postcanines generally like early homo o M3 M2 M1 like early hominins o M1 M2 M3 humans Shoulders Arms capability to have o Could have spent more time in trees primitive shoulders o Superiorly narrow thoracic cage o Humans barrel o Probably spent more time in the trees o Had larger muscle attachments o Humanlike finger ratio thumb lengths o Curved phalanges o Iliac blade like a afarensis o More efficient in bipedalism o Wide flaring hip bones very primitive o Angled o Clear valgus angle knee o Longer o Curve phalanges Pelvis Thigh Tibia Feet Homo features o Skull is derived but size is small o Hands and versatile o Teeth are derived o Feet humanlike o Long legs Australopithecine features o Primitive shoulders o Flared pelvis o Curved fingers Sexual dimorphism November 5 2015 The bones themselves humanlike magnitude of sexual dimorphism roughly 20 o Reconstructed cranial capacities hand and foot sizes indicate o Males a bit under 5 tall females a bit over 4 tall o No evidence of carnivore or scavenger modification o Some snail and beetle modification o No evidence of diseases or disorders o Only two antemortem fractures o Very mild normal arthritis o not fossilized Behavior Systematic refutation of every imaginable alternative to deliberate placement o No death traps no carnivore scavenger accumulation no Dinaledi Chamber has always been in the dark zone according to disasters geological analyses o How d they get in there without fire Fantastic glimpse onto range of normal variation in a population of Rising Star Lessons extinct hominins o Beware overintrepretation of scant data Where does homo naledi fit in our evolutionary tree We don t know yet Who were the earliest African Emigrants Hominins migrated to Asia and Europe descended from earlier Acheulian stone tool industry from the early and Middle Pleistocene African ancestors bifacial tools Homo erectus upright man The Morphology of Homo Erectus Indonesia Intermediate but more modern characteristics 1890s Dubois First one to leave Africa 1 8 Ma 250 Ka Body Size some H Erectus adults weighed well over 100 pounds Brain size H erecturs shows considerable brain enlargement with a Cranial shape thick cranial bone large browridges and projectile with an average adult height of about 5 feet 6 inches cranial capacity of 700 to 1 250 cm 3 nuchal torus at the back of the skull Crania Homo erectus in Asia peking man Morpholohy and Variation in homo erectus o Little forehead development o Cranium wider at base o Saggital keel Zhoukoudain china Davidson Black Franz Weidenreich 700 400 000 Ka 40m f adults and children WT 15000 from Kenya is the most complete H erectus specimen Dates to 1 6Ma Dmanisi in Republic of Georgia o Human remains 1 8 Ma Homo erectus Nariokotome Boy Eurasia and Western Europe yet found Europe 800 000 Ka o Came from northern Africa Ceprano Central Italy o 900 Ka 350 Ka Dmanisi 1 8 1 7Ma first fossil skull old man had no teeth Dmanisi Hominins Early 1990s anywhere outside of Africa These remains are the best preserved hominins of this age found They show a mixed pattern characteristics some quite unexpected 5 fossilis first possible emigrants out of Africa o because they have a very small brain size 600 780 cm3 o low braincase wide base sagittal keeling the dmanisi crania have similarities to H erectus while some characteristics are different from other hominin finds outside of afrca a number of stone tools similar to early ones from Africa have been recovered at dmanisi Newest evidence from dmanisi o Not tall 4 9 5 5 o Body proportions similar to H erectus and H sapiens Challenges of identifying species Anagenesis Cladogenesis o Transformation of a single species over time o Formation of one or more new species form another over time Culruew od Homo erectus Move out of Africa Refined stone tool industry o Fire o