Primate Origins 2 13 14 2 18 14 Paleocene Eocene Oligocene Miocene Pliocene Where do we look for early primates Most primates live in topical subtropical areas and most are arboreal When to look for earliest primates Continents completely apart by Oligocene Paleocene Plesiadapiforms infra order o Archaic primates or primate like mammals o Characteristics Primate like apomorhphies Dental formula 2 1 3 3 Mammals 3 1 4 3 Humans 2 1 2 3 Flattened Blunt molars Petrosal Bulla debatable Arboreal Shift toward frugivory eating fruit Non opposable hallux big toe Claws Un fused mandibular symphysis Long snout retained olfaction No post orbital bar o Ancestral colugos Order Demoptera Paromomyidae Carpolestes o Characteristics No post orbital bar or convergence Opposable hallux and nails Big Questions o Causes of Primate Origins Arboreal hypothesis Primate features are adaptations to life in trees Squirrels Vision predation hypothesis Adaptations toward being able to find insects fruits flowers Dietary Shift Eocene 55 38 mya Fruits and Flowers Radiation of rodents in North America coincides with extinction of plesiadapiforms First True Primates o Early Prosimians Trends Reduced olfaction Complete post orbital bar frontation Opposable hallux big toe Nails Foliverous frugivourus o Adapidae Characteristics Dental Formula 2 1 4 3 Fused mandibular symphysis Post orbital bar Long snout Arboreal Diurnal Sexual dimorphism o Omomyidea Characteristics Dental Formula 2 1 3 3 Unfused symphysis modern tarsier Post orbital bar Shortened snout Arboreal Nocturnal No dimorphism o Eosimidae mid eocene Characteristics Very small 3 ounces Anthropoid Apomorphies Spatulate incisors Enlarged canines Broad premolars Derived molar cusps Big Questions o Radiation of prosimians Coevolution with angiosperms o Extinction of Prosimians Competition with bats o Who begat whom Adapidae lemurs Omomyidae tarsiers o Whence the anthropoids Eosimidea Oligocene 38 25 mya Basal base anthropoids Monkeys First South American fossil primates o Many found Fayum Egypt desert Parapithecids o Characteristics Dental Formula 2 1 3 3 Fused mandibular symphysis Incipient bilophodont molars Post orbital septum Fused frontal bone Leapers Basal anthropoids Propliopithecids o Characteristics Dental formula 2 1 2 3 Oligopithecines o Odd mixture of plesimorphies p and apomorphies a Honing complex Bony ring on outer ear Size increase Sexual dimorphism Basal Catarrhini OWM Apes Humans Big Questions o Whence Platyrrhini Small brains p Unfused mandible p 2 1 2 3 a Post orbital closure a Rafting hypothesis Northern Origin Antarctic Land Bridge Earlier Origin Miocene 25 5 5 mya Golden age of the apes Hominoids Ancestral stoke from Aegyptopithecus Propliopithecid Environment General cooling trend tectonic activity o Uplift of continent East African Rift System Increased volcanism Great primate diversity in early and middle Miocene o Middle Miocene sediments o Late Miocene Hominoids widespread Africa Europe Asia Uplift of Himalayas climate change Siwalik Cooling dryer and fewer primates Messinian crisis 6 4 mya drying of Tethys sea Victoriapithecus early Miocene African monkey Miocene hominoid trends o Body size increase o Loss of tail o Shortening of face Prognathic Orgnathic o Flaring of the Zygomatic arches o Relative brain size increase o Deep robust mandibular bodies Low rounded cusps Y 5 cusp pattern on mandibular molars Proconsulids 27 17 mya o Africa Saudi Arabia o Characteristics Arboreal Quadruped No tail Lightly built jaw Thin enamel o Afropithecus More derived Thickened enamel Flared base of cheek teeth o Brachiation Swinging motion Middle Miocene o Dryopithecines Oreopithecus Europe Could have been bipedal o Sivapithecines Asia Ramapithecus Sivapithecus A CAUTIONARY TALE Characteristics Arch shaped palate U shaped o Gigantophithecus 9 0 5 mya Characteristics More orthognathic face homoplasy Small canines Female Thick enamel homoplasy Low grinding teeth homoplasy Wear gradient on molars long development Bipedal Hominin Ancestral Orangutan Huge teeth robust mandable Thick enamel Dental caries 6 tall 400 600 lbs All based on teeth and mandable Ate Phytoliths of bamboo seeds and fruit Extinct 0 5 may Middle Late Miocene o Otavipithecus 13 mya Characteristics Thin enamel Slender mandable Y 5 o Kenyapithecus 16 14 mya Robust mandable Thick enamel Wear gradient M1 M3 Reduced canine o Equatorius 15 mya Closely related to kenyapithecus Baboon sized terrestrial ape Miocene Big Question o Who is our ancestor