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Plants and People. Chapter 21. Human origins. Australopithecus robustus 1 mya. 7 mya - diverged from ancestors of living great apes 5 mya immediate antecedents ( Australopithecus ) first appeared 2 mya – Homo first appeared 1.4 mya fire use 500,000 ya H. sapiens
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Plants and People Chapter 21
Human origins Australopithecus robustus 1 mya • 7 mya - diverged from ancestors of living great apes • 5 mya immediate antecedents (Australopithecus) first appeared • 2 mya – Homo first appeared • 1.4 mya fire use • 500,000 yaH. sapiens • Africa origin • 250,000 ya Eurasia Homo habilis A. garhi H. erectus A. africanus H. sapiens A. robustus A. aethiopicus A. boisei Australopithecus anamensis A. afarensis 5 mya 4 mya 3 mya 2 mya 1 mya present
Human origins • Neanderthal people • 34,000 ya disappeared from Europe & Asia • replaced by modern humans • migrated over entire globe • reach North America 14,000 ya • hunter-gatherer society
Human agriculture origins • 11,000 ya • some people turned to food production • domestication of wild plants and animals for food • not all people developed agriculture Centers of food production, from Diamond, J. 1997. Guns, Germs, Steel: The Fates of Human Societies.
Agriculture origins • plant selection and cultivation • select few eatable species • grow in great numbers • 90% of biomass on acre of land • result: • feed 10 to 100X more herders & farmers compared to hunter gatherers
Organisms for Food • Most biomass • wood & leaves • Most food useless for food • indigestible (like bark) • poisonous (monarch butterflies & death cap mushrooms) • low in nutritional value (jellyfish) • tedious to prepare (very small nuts) • difficult to gather (larvae of most insects) • dangerous to hunt (rhinoceroses)
Agriculture origins Fertile Crescent • initial plants (by 8,500 ya) • barley • wheat • pulses soon following • lentils • peas • additionally • chick peas • vetch • olives • dates • pomegranates • grapes • flax Fertile Crescent. Origin of agriculture, extends into what now is known as Lebanon, Syria, Turkey, Iraq, Iran, Jordan, Israel.
Agriculture Foundations • Traits of domesticated plants of the Fertile Crescent • annuals • energy to produce BIG SEEDS • advantage for Mediterranean climate: must withstand dry season and grow quickly when rains fall • wild ancestors already abundant & highly productive • 50 calories of food energy / calorie of work expended from harvesting • thus storage of seeds were possible • two traits easily selected for with cultivation • breakdown of natural seed dispersal & germination inhibition • high % of bisexual selfers • tended to “breed true” with occasional mutant • high protein content in 3 of first 8 selfer cereals • 8-12 % protein; far higher than rice or corn
Agriculture Today • cereals • wheat • corn • rice • barley • sorghum • soybean • roots/tubers • potato • manioc • sweet potato • sugar sources • sugarcane • sugar beet • banana • 350,000 angiosperm species • few hundred domesticated • dozen species account for 80% of crops worldwide “Our failure to domesticate even a single major new food plant in modern times suggests that ancient peoples really may have explored virtually all useful wild plants and domesticated all the ones worth domesticating.” Diamond, 1997
Human origins • major five • sheep • goat • cow • pig • horse • minor nine • Arabian camel • Bactrian camel • Llama or alpaca • Donkey • Reindeer • Water buffalo • Yak • Bali cattle • Mithan • domesticated animals • meat (replaced wild game protein) • milk • fertilizer • pulling plows