Hominin Evolution Review Sahelanthropus Tchadensis 7 6 MYA Earliest hominin Small teeth thick enamel Short face Decreased prognathism Large brow ridge Slightly more centralized foramen magnum Combination not seen in fossil apes or later hominins Orrorin Tugensis 6 5 8 MYA Earliest post cranial remains Ape like canines Fossils suggest both arborealism and bipedalism Ardipithecus Ramidus AKA Ardi 5 8 4 MYA Small brain case Reduced canines cooperative groups Central foramen magnum Short broad ilium Divergent hallux Long curved phalanges Environment patchy forests Most complete early hominin Australopithecus Anamensis 4 2 3 9 MYA Large canines Thick enamel Molar width intermediate bipedal Australopithecus Afarensis 3 7 3 0 MYA Various habitats Ape like features small brain prognathism curved phalanges Bipedal knee joint fossil footprints Lucy sexual dimorphism found near Lake Shore with 5 adults and 2 children Laetoli Footprints no divergent bigtoe at least 2 adults Australopithecus Africanus 3 3 2 5 MYA Less prognathism More gracile Smaller teeth Bipedal Human like pelvis Spinal curve more human like Straight phalanges Taung Child Homo Habilis 2 4 1 8 MYA Increased brain size Less orbital constriction Habitual biped Smaller face and teeth Increased reliance on cultural adaptations Stone tools Possibel speech capabilities Ancestral traits short stature long arms short legs inefficient biped Derived traits dentition larger incisors smaller molars dental arcade precision grip Paranthropus Robustus 2 1 4 MYA South Africa Slight sagittal crest Robust large molars and smaller incisors Homo Erectus 1 8 MYA 250 KYA Increasing body size Increasing brain size Cranial shape brain arrangement Change in limb proportions Obligate biped Cranial capacity 1000 cc Long and low brain case Widest at base of skull Thick cranial bones Large supreorbital torus supraorbital sulcus Sagittal keel only asian forms Moderate prognathism Some post orbital constriction Nasal bones project Fire first hominin outside of Africa Homo Heidelbergensis 700 200 KYA Large supraorbital torus Receding forehead Long low craniu Large mandible Thick skull bones No chin Average cc 1200 cc Expansion of cranium reduced post orbital constriction rounder occipital region expanded sides of cranium Occipital bun mid facial prognathism Double arched upraorbital torus Intentional burial 6 foot wooden spears Homo Neanderthalensis 130 KYA 28 KYA Average cranial capacity 1520 cc EQ 4 8 Long low skull Occipital bun Receding forehead mid facial prognathism Double arched supraorbital torus No chin Robust limb bones Same hegith as modern humans in cold environments Speech Accelerated childhood meat diet clothing Mousterian tools Jewelry paitings Flexed burial grave goods Homo Floresiensis 27 KYA Very small 3 ft tall Has all of the derived features of larger homosapiens Gracile face Tools cc 600 large compared to body size Island dwarfism Homo Sapiens 200 KYA present cc 1400 cc EQ 5 3 5 8 Short high skull No post orbital constriction Reduced supra orbital torus Orthognathic fae Small teeth CHIN More gracile Capable of speech Explotation of new materials bone ivory antlers flint New inventions fish hooks arrow points needle