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Anthropology. The emergence of genus Homo. Early Homo, particularly erectus, we see a huge gain in size of brains. Why? Brains make up 2% of body weight, but consume about 20% metabolic energy This cannot be sustained by nuts and fruit We needed protein! Explanation?. Brains!.
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Anthropology The emergence of genus Homo
Early Homo, particularly erectus, we see a huge gain in size of brains. Why? • Brains make up 2% of body weight, but consume about 20% metabolic energy • This cannot be sustained by nuts and fruit • We needed protein! • Explanation? Brains!
Brains brought us tools, and tools brought us meat. Meat helps balance the metabolic budget. • A very cool adaptation occurred…. • Bigger brains=tools=meat=more energy=but ALSO: meat is easier to digest, and as Homo’s brains got bigger, their intestines got shorter at the same time (unusually small for primates). Now: meat gives brain protein, and we can digest easier as we’ve evolved. Brain size
1.6-2.3mya • First discovery had cranial size of 752cc • Smooth rounded head, lacking brow ridge • Human-like parabolic dental arcade (rather than U shaped like apes and australopithecus) • Found near stone tools (biggest reason along with brain size for “new species”) H. Habilis
Tale of thee areas (China, Africa, Indonesia) • Ranges of 850cc-1,200cc (not much smaller than H. Sapiens…us) • Acheulean Tools (hand axes) distinct artifacts • Movius Line H. Erectus
1.65mya-100,000ya (possibly) • Characterized by crafting and use: Bifacial (worked on both sides) Acheulean Tools
Finds in Indonesia (islands!) • Finds in China (Peking Man) • Close to Beijing (Peking) a limestone cave produced many discoveries…. H. Erectus
Fire! • China vs Africa. Which one would NEED fire? • Evidence: *carbon deposits * Ash accumulations (controlled fire sites)? *Burned bone (does this mean cooking?)? *Fire-cracked stone • Is the above proof that they made/created fire? Peking Man
Ash Accum.: rain could have washed in • Burnt Bones: Hunters or gatherers? • Bone could be part of scavenge process • Picture a group chasing predator away with fire torches and “stealing” the catch…. Peking Man
Olduvai Gorge (Tanzania) 1.4mya • Turkana Boy! The most famous/informative erectus find in Africa (67/207 hominoid bones) In Africa…
Male (based on pelvis, robustness of skull) • 2nd molars newly erupted (what does this mean?) • Epiphyseal fusion in some bones: elbow, hip bone (what does that mean?) • Erectus would mature faster than humans due to smaller brain size (estimate Turkana boy to be 10-12 yrs old rather than 13 as a human) • Brain was 880cc, but could have matured to 910cc? He lived 1.6mya. Turkana Boy
2004 an odd find on an Indonesian island • Dubbed “the Hobbit” as Lord of Rings came out that year….. • 1 meter tall, cranial capacity: 380-410 (same as chimp), and lived only 17,000yrs ago; much later than anything other than Homo Sapiens had gone extinct H. Floreiensis
Very short, no forehead really, and extremely long feet: 10 times longer than most human ratios (foot to femur) • Brain was small, but did exhibit same function of erectus brains (higher brain functions) • Found alone, maybe a mutation, but she was not found alone…. • Sophisticated stone tools H. Floresiensis
Island dwarfism: Looking at 116 island mammals, 38 were smaller, 12 were same size, and 66 were larger than on mainlands • Exs: Carnivores: 13/15, Insects: 4/5 got smaller • Exs: Rodents: 60/69, Marsupials: 3/6 got bigger • Small got big; and big got small • Small because of fewer resources? Bigger bodies are at a disadvantage Why so small?
Exs: Deer on Vancouver island, elephant ypes are well doc’d (sometimes 50% smaller) • Brains 50 % smaller as well. Remember why? Put it all together….
Archaic H. Sapiens…400,000-600,000yrs old • Found in Europe (Germany, France, Spain, UK, Greece) • No chin, smooth cranium, thinner cranium • Cranial Capacity: 1,000-1,200 H. Heidelbergensis