Study Guide Primates and Human Evolution Describe the traits of primates.! Classify yourself taxonomically.! What traits make you human?! Describe the evolutionary trends in hominin species over the past 5-7 million years.! List and describe four hominin species most closely related to modern humans. Where do you fit into the natural world? Linneus system: Kingdom Animalia Phylum Chordata Class Mammalia Order Primates Family nidae Genus Species sapiens Characteristics of Primates You re a primate! What does that mean? hands and feet: brain and jaw sizes: eye position: parental care, complex social behavior fingers & toes w/ fingernails
What makes us humans? Humans distinguished from other hominids by: Upright posture, bipedal locomotion Larger brains (V brain /M body ) Language capabilities (communication language) Jaw: Symbolic thought (considerable debate!) Complex tools (define complex ) Human Evolution Fossils like you: 160,000-190,000 y.a. Prior to that, no sapiens Where did we come from? there are other fossils that look a similar to us... Paleoanthropology 0 0.5 boisei robustus ergaster? neanderthalensis sapiens def = study of human origins what data/evidence? fossils of approx. 20 species of extinct hominoids closer to modern humans than to modern apes. hominins humans + ancestors fossils as far back as ~7mya Best explanation so far for the evidence: Hominins originated in Africa split from early chimp lineage: ~7 mya What would early hominins look like? (brain? locomotion? teeth? jaw? tools?) Millions of years ago 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 Kenyanthropus platyops anamensis Ardipithecus ramidus Orrorin tugenensis africanus Sahelanthropus tchadensis garhi afarensis rudolfensis habilis erectus
Trends in Hominin Evolution Hominin evo characterized by changes in: brain size posture/locomotion tool use jaw/face shape, tooth size skeletal robustness body size Millions of years ago 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 Focus on AHENS: Kenyanthropus platyops anamensis africanus boisei garhi robustus rudolfensis habilis ergaster? neanderthalensis sapiens erectus 4.5 5.0 5.5 Ardipithecus ramidus afarensis also: heidelbergensis 6.0 Orrorin tugenensis 6.5 7.0 Sahelanthropus tchadensis Early hominins were NOT chimpanzees (nor modern monkeys) Human evolution was NOT a ladder/tree leading directly to sapiens more like a bush Correcting misconceptions
Ardi Ardipithecus ramidus 4.4 my old bipedal, tree-dweller 4 tall, small brain afarensis 3.9-3.0 mya Height: 3.5 Brain size: 500cc Lucy, Don Johanson, 1974 40% complete Laetoli footprints (Mary Leakey) habilis Handy man Richard Leakey, 1972 2.4-1.2 mya Height: 5 Brain size: 500-800cc Characteristics: Broca s area, tools erectus Java Man, Eugene Dubois, 1891 upright man 1.9-0.3 mya Height:up to 6 Brain size: 750-1225cc Characteristics: fire, out of Africa KNM-ER 1470 KNM-ER 3733
floresiensis neanderthalensis Johann Fuhlrott, 1856 230-30 kya Height: 5 8 Brain size: 1450cc Characteristics: adapted to cold, buried their dead, Europe and Middle East Disappear w/in 1000 yrs of contact w/ H. Sapiens Discovered in 2003 95-13 kya Height: 1M Brain size: 380-417cc Characteristics: dwarfed hominid from Indonesia, found with complex tools. Descendent of?. BH-030 sapiens 190 kya-present Height: 6 Brain size: 1350cc Characteristics: wiped out Neaderthals(?), cultural explosion about 40kya BC-093 Skull LB1 with a! modern human skull
Humans left Africa H. erectus (H. ergaster) probably first to leave H. sapiens evolved first in Africa erectus disappears, replaced by sapiens How/Why? possible mechanisms: Multi-regional hypothesis Replacement hypothesis other? Evolutionary models Multi-regional model: Replacement model: Assimilationmodel mtdna: