1 / 36

ORIGIN OF AGRICULTURE

ORIGIN OF AGRICULTURE. Cultural Ages. Archeologists have divided the cultures of the past into ages based on materials used for making tools: Stone age Old Stone Age - Paleolithic New Stone Age - Neolithic Bronze Age Iron Age. Tools and Technology.

zahina
Download Presentation

ORIGIN OF AGRICULTURE

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. ORIGIN OF AGRICULTURE

  2. Cultural Ages • Archeologists have divided the cultures of the past into ages based on materials used for making tools: • Stone age • Old Stone Age - Paleolithic • New Stone Age - Neolithic • Bronze Age • Iron Age

  3. Tools and Technology • Obviously more science need to make a bronze tool than a stone one • Knowledge of geology to find the ore • Chemistry to form the material • So even though the terms apply to cultures there is a great deal of technology that is implied in these terms.

  4. Stone Age Periods • Paleolithic Period - humans existed by foraging: • Hunting, fishing, gathering wild berries, roots, seeds, etc • Number of people restricted by food available in the area • Neolithic Period - people controlled there own food supply by cultivating plants and breeding animals

  5. Major Change in Neolithic Period • Possible to feed more people than yourself • This allows for populations to increase • This leads to communities • To cities and to advanced civilization • Without agriculture advanced civilizations would not be possible

  6. Neolithic Revolution • Man’s shift to food production by domesticating plants and animals was a revolutionary change in human history • Called Neolithic Revolution or Agricultural Revolution • But when, why, and how did the change occur?

  7. Human species • Human species (Homo sapiens) has existed for possibly as long as 400,000 years • For most of that time, humans survived as foragers or hunter-gatherers, gathering wild plants and hunting animals

  8. Shift in Human Enterprise • Around 10,000 years ago this shift from foraging to farming occurred in many areas • Arose independently in different areas of world • This formed the basis of advanced civilization in both the Old and New World • Over the centuries agriculture spread • Foragers gradually became restricted to marginal areas

  9. Foraging Societies Today • Largely disappeared • Comprise only a tiny percentage of the human population • Limited to a tropical rain forests, deserts, savannahs, tundra, and boreal forests • There may be only around 250 foraging groups (many of these partly agricultural)

  10. Diet of Foraging Societies • Evidence indicates they had a varied diet • They were (and are) well fed • Most groups use a lot of plants in their diet (there are some exceptions like the Eskimo who eat fish and meat). • Study of the Kung people of Africa show that hunter-gatherers have a thorough knowledge of the botany in the area.

  11. Foragers are SkilledBotanists Foragers know • which plants are edible or poisonous • which are medicinal or psychoactive • which are sources of dyes • which used for weaving or building materials • remarkable methods to prepare edible foods from plants with toxins such as cassava which contains hydrocyanic acid

  12. Neolithic Revolution • About 10,000 years ago archaeological evidence indicates that human cultures began the practice of agriculture in several different areas of the world • Over the next few thousand years in the Near East, the Far East and Mesoamerica agriculture flourished

  13. Why did people switch to agriculture after thousands of years of foraging? • Legends among different groups • “A gift from the gods” - Egyptians, Greeks, Aztecs • Many theories focus on a wise person or brilliant sage (Genius Theory) • If you sow seeds, a plant will grow. • Dump Heap - discarded seeds at dump sites (manure good fertilizer) • Primitive burial - bury food with the dead *** Last 3 are all variations on same theme

  14. New Theories • Beginning in 1960, archaeologists questions the old theories • Agricultural was a gradual cultural evolution not a revolution • Hunter-gatherers knew the wild plants, knew how they grew, and would incorporate farming along with foraging as part of an overall food collection strategy when necessary

  15. People knew plants • No need to cultivate because there was abundant food for foraging • Environmental change made the difference • Lots of suggestion as to what that environmental change was • Some say last Ice Age • Some say population pressure • Whatever the cause, people began using their botanical knowledge in cultivation

  16. Transitional stage between foraging and agriculture? • Foraging groups formed settlements but sent out members to hunt and gather • This permitted populations to increase • Transitional stage lasted for several thousand years in some locations until resource stress or environmental change led to the switch to agriculture.

  17. Environmental Stress • In the Near East, for example, archaeologists believe that the climatic dry period around 11,000 years ago brought about a change in the distribution of cereal grains (especially wheat and barley). • Applying their botanical knowledge, these foragers gradually changed from collecting these wild cereals to cultivating them.

  18. Early sites of agriculture: • Many sites of early agriculture in both the Old and New Worlds • Agriculture dates back approximately 10,000 years in Near East, Far East, and also in the New World • The oldest site in the Far East - about 11,500 yrs ago - This site most recent discovery

  19. Early Sites of Agriculture

  20. Near East • Some of the best studied sites of agriculture are in southwestern Asia • In foothills around the FertileCrescent • Area around the Tigris and Euphrates River is a particularly rich area for archeologists especially the foothills of Zagros Mts in Iraq and Iran

  21. Near East

  22. Agriculture in the Near East • Barley domesticated first - about 10,000 years ago • Two kinds of wheat • Einkorn wheat • Emmer wheat • Other crops - peas and lentils • Domesticated animals: dogs, goats, sheep

  23. Far East • Several locations in Far East including China and Thailand • Yangtze and Yellow River Valleys in China are well sited sites

  24. Far East

  25. Agriculture in the Far East • Current studies indicate that rice cultivation began approximately 11,500 years ago along middle reaches of the Yangtze River • Predates agriculture in Near East by 1,500 years • Other crops foxtail millet (about 8000 yrs ago), broomcorn millet, rapeseed, and hemp • Animals include cattle, pigs, dogs, poultry

  26. New World • Various sites in Mexico and Peru • Best studied sites in Tehuacan Valley of central Mexico • In caves in Tehuacan Valley archeologists have reconstructed lives on inhabitants over a 12,000 year period. Initially people foraged but later made transition to agriculture • Recent site is Oaxaca, south of Tehuacan

  27. New World Oaxaca

  28. Agriculture in New World • Impressive variety of plants but few animals • Squash domesticated about 10,000 yrs ago • Corn about 5,500 years ago • Amaranth, gourd, 3 species of bean, chili peppers, tomato, peanut, guava, sunflower, avocado, white potato, sweet potato • Animals - dogs, turkeys, llamas

  29. Characteristics of Domesticated Plants • Plants that have been domesticated are genetically distinct from the wild ancestors • Domesticated plants are subject to artificialselection to suit human need rather than natural selection

  30. Natural Selection • Natural selection is the process that insures that wild organisms will survive in the environment • Variation in traits occurs in a population • Those organisms that are best adapted to their environment will survive • Those that survive have offspring and pass on desirable traits to offspring

  31. Artificial Selection • Once a plant is domesticated, traits are selected to suit human needs (not survival in the wild) • Some of the traits that are selected might be detrimental to survival in the wild • Corn cobs are covered with husks and have no way to disperse seeds

  32. Wild and Domesticated Grains • Most wild grasses have shattering fruiting heads which break apart easily and scatter their seeds over a wide area • A recessive gene gives a tough spike with a non-shattering head • It would be natural for early foragers to gather seeds attached to tough spikes • When agriculture began these would be planted and pass on non-shattering trait

  33. Other Traits • Artificial selection would result in larger seeds, or fruits, or tuber • Over time the domesticated varieties would be larger • Wild barley has two rows of grains while domesticated varieties have six rows • We continue to use artificial selection today

  34. Centers of Plant Domestication • There appear to be several major centers of origin of our domesticated crops • The majority are in the Old World • Fewer are in the New World • These areas show the greatest diversity of particular crops • From here most of the major crops have spread world-wide

  35. Importance of Centers of Diversity • Because these centers show the greatest diversity, the genetic variation present is important • Genes for hardiness, genes for disease resistance, genes for drought tolerance may all be present among the variation • Scientists hunt for these sources of variation

More Related