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The Human Race. Our Origins. Evolution of Primates. Primates Mammals with 5 flexible fingers Earliest dwelled in trees-arboreal Needed special adaptations for this: Opposable thumb….Why? Binocular vision Eyes in front of head Field of vision of eyes overlap—depth perception….Why?
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The Human Race Our Origins
Evolution of Primates • Primates • Mammals with 5 flexible fingers • Earliest dwelled in trees-arboreal • Needed special adaptations for this: • Opposable thumb….Why? • Binocular vision • Eyes in front of head • Field of vision of eyes overlap—depth perception….Why? • Rotating Shoulders
Evolution of Primates • Primates divided into 2 groups: prosimians and anthropoids • Prosimians • First primates • i.e. Loris • 30-40 million year fossils show they were common • Nighttime hunters… How can you tell?
Evolution of Primates • Anthropoids • Monkeys, apes, and humans • Smaller eyes--day active primates • Color vision • Larger brains • Replaced prosimians rapidly
Anthropoids • Anthropoids—3 categories • Monkeys • Have tails • Old World—Asia and Africa • New World—Central and S. America • Apes • NO TAILS • Larger brains than monkeys • Chimps, gibbons, orangutans, bonobo, etc. • Humans • Our closest genetic primate relative is?
Evolution of Humans • Vocab: • Bipedal: walk upright on two legs • Hominid: bipedal primates such as humans and their closest fossil relatives
Hominids • Hominids are the ONLY bipedal primates: • Locking knee joints • Spine enters skull at bottom of head • Femurs (thigh bone) tapers in • Big toe in line with others Laetoli Footprints
Hominid vs. chimpanzee • Chimps most closely related primate to humans—95% similarity in the sequence of our genes! • Human’s jaw more arc shaped with smaller canines; chimps’ U with larger canines and larger gaps. • Hominid spine S– chimps’ is C shaped • Hominid pelvis is bowl-shaped, chimps’ long • Hominid thigh bones taper in—chimps’ out • Human Evolution Video Clip
Early Hominids • Darwin Descent of Man • 1871 • Said fossilized remains of ape and human common ancestor should be found in Africa
Early Hominids • Genus Australopithecus • LucyAustralopithecus afarensis • Fossil found in Africa • Hominids—shape of pelvis and femurs showed they were bipedal. How? • Short—3’6’’ • Brain size of chimps • Jaws more rounded than apes • Teeth like humans
LUCY 3.5 million years old 40% complete Female
Showed us: • walked upright • first • brain size grew • AFTER.
SKULLS • Lucy had a small skull like an ape, but she wasn’t one. • LUCY APE
SKULLS A. afarensis (Lucy) Homo sapien
LUCY • She walked upright • She was a bipedal hominid • Bowl-shaped pelvis • Thigh bones taper in • Locking knee joint
Early Hominids • Genus Australopithecus A. afarensis • Genus Homo Homo habilis H. erectus H. sapiens NOT A COMPLETE LIST! THERE ARE OTHERS! Time
APESHomo sapiens Homo erectus transitional species Homo habilis Australopithecus afarensis common ancestor to ape and H. sapiens
Homo habilis • Means: Handy man • Small structure like Lucy • Skull 2X’s the size of Lucy • 2- 1.8 mya in Africa • Tools made of bone and stone.
Homo erectus • Peking man • Africa / Asia / Europe • Larger than H. habilis • Larger brain • Excellent tools, used fire • 1.5 mya – “immediate” ancestor
Where Did H. sapiens evolve? • Two hypotheses: • Out of Africa: • idea like Darwin’s • states H. sapiens evolved IN Africa and spread to rest of world • Multiregional • H. erectus left Africa and THEN evolved into H. sapiens • Out of Africa hypothesis supported by most evidence—fossils of modern-like humans found in Africa H..sapiens H. erectus H..sapiens H..sapiens H. erectus H..sapiens
Early H. sapiens • Homo neanderthalensis -discovered in Neander Valley in Belgium • Massive skulls, protruding brows • 400,000-100,000 years ago • Great controversy- did they die off (genes no longer) or did they evolve with us (interbred so genes still in our gene pool)? • Modern H. sapiens probably evolved in Africa and replaced Neanderthals.
APESHomo neanderthalensis Homo sapiens Mated???? Homo erectus transitional species Homo habilis Australopithecus afarensis common ancestor to ape and H. sapiens
NEWSFLASH!!!!! • 2009 Recent analysis of Ardipithecus ramidus… aka “Ardi” found in 1994. • A hominid with opposable big toes like chimps and apes • 1.2 million years OLDER than Lucy, and our oldest known common ancestor with other primates (4.4 mya)! • 47 inches tall • Show that chimps have actually evolved MORE than humans since our common ancestor
APESHomo neanderthalensis Homo sapiens Mated???? Homo erectus transitional species Homo habilis Australopithecus afarensis common ancestor to ape and H. sapiens ARDI?????