1. Agriculture and DomesticationAgricultureCultivation of plants and animals for human useRemove certain species to focus nutrients, light and water on other species. (weed them, eradicate animals, etc )Most of the world works as farmersWe not only are influenced by evolution but we are also involved in influencing the factors of evolution (direct, indirect ways we influence evolution)The Origins & Diffusion of AgricultureThe Neolithic RevolutionBegins around 10,000 B.P. (8000 BC)Appears in several independent locationsindigenous crops that were able to be cultivatedDomesticationGradual, Unplanned ProcessHunting  Selective Hunting  Herding  Selective Breeding  (Genetic Modification?)Plant domestication: Most of the World’s food is, directly and indirectly, provided by: 14 cropsIn order of importance: Wheat, Rice, Maize, Potatoes, Sweet Potatoes, Manioc, Sugarcane, Sugar Beet, Common Beans, Soybeans, Barley, Sorghum, Coconuts and Bananas2. Why did Hunter Gatherers Shift to Agriculture?In a Resource Rich Environment , Hunting and Gathering (Produces 50 kcal of NRG per 1kcal expendedAgriculture Produces 17kcal of NRG per 1kcal expendedWhat is the incentive to switch to agriculture?Population Growth – best reasonDemographic Hypotheses!Agriculture provides more NRG per Unit of Land!Hunting Technology  Increasing Population  Less Resources  Reduced Mobility  Agriculture & Intensification of Land UseAgriculture is an “Auto-Catalytic” Processincrease in population  increase in the intensification of AgricultureLoss of Hunting & Gathering Knowledge --> Dependency3. Grain-Legume Complexes and ExamplesFound in Major Centers of DomesticationLegumes act as "Nitrogen Fixers"Bacteria Nodules on RootsLegumes tend to have bacteria and live in a symbiotic relationship where the waste product is nitrogen.Plants need nitrogen in order to live.Serves Two Functions:(1) Maintain Soil Fertility(2) Provide Carbohydrates & ProteinIn our three main sources of crops, each had grain legume complexes4. Centers of Domestication and some major cropsFarmland and People (2000)Location: Asia, Africa, North America, South America, Europe, Australia , WorldAsia – intensive, more laborNorth America - extensive use of the landSouthwest Asia (8500 B.C): Wheat, barley, pea, lentil, chickpea, etcFertile Crescent (Iran, Iraq); Independent originAgriculture diffused from the Fertile CrescentWheat (carbohydrate), peas (protein)China (7500 BC)Millet, Rice (main crop), Soybean, Pig, Silk WormMillet grows in drier environmentsIndependent OriginIndus Valley (7000 BC not independent)Pakistan (modern-day)Sesame, Eggplant, Humped Camel, PigsEgypt (6000 BC, not independent)Fig, Cat, DonkeyAgriculture from Fertile Crescent  EgyptWestern Europe (6000-3500 BC)oats, poppy, ryenot independentMeso-America (3500 BC)Corns, Beans, Squash, TurkeyColumbian Exchange  CornAndes & Amazonia (3500 BC)Potatoes, Manioc, Llama, Guinea PigNew Guinea (7000 BC)Sugarcane, BananaSahelian Africa (5000 BC)SorghumEthiopiaCoffee, TeffWest Africa (3000 BC)African Yams, Oil Pams, etcEastern North America (2500 BC)Goosefoot, Sunflowers5. The Green RevolutionNot an environmental revolutionAgricultural Innovations from mid 1940s to 1970sNormal Borlang (1914-2009)Led to dramatically increased Food Yields n the Developing World (India, Philippines, Mexico, etc)Involved . . .High Yielding Varieties (HYVs)New Management PracticesNew forms of InputsMechanization of agriculture in the developing world large food increase, food productionCritiquesIndustrialized AgricultureFossil FuelsWorsened environmental problemsBenefited Wealthy Farmers6. Environmental Impacts of Agriculture(1) Soil ErosionWind & WaterAir QualityPlowing  soil erosionSlash & Burning  soil erosionOvergrazing(2) Declining Soil FertilityCaused by soil erosion, Leeching & Crop RemovalLeeching in wet areas, tropical areasSome Strategies to Combat Declining Soil FertilityFallowingThe practice of leaving a field idle for a periodBuilds up nutrients and moisture for the next cropCrop Rotation (“Nitrogen fixers”)(3) Habitat Change & Reduced BiodiversityMono-cropping – single crops are grown in one area, ex: cornfields for miles – big issue in agricultureSimplified Morphological StructurePlanting in RowsComplex, LayeredHydrological ChangesIrrigation, Dams, Ground Water, etcWhere are they taking the water from and how will that impact the environment?(4) Fertilizers & EutrophicationRelated to fertilizer use – EutrophicationHeavy use of Fertilizers & Livestock Manure  Nutrients enter Water Bodies  Increased Algae Growth  Algae Die & Decompose  DeOxygenation of Water  “Dead Zones”Fish and other types of aquatic life need oxygene.g. The Susquehanna River and the Chesapeake Baye.g. The Growing "Dead Zone” in Gulf of MexicoChina has serious problems with Eutrophication(5) Pollution from Pesticides & HerbicidesKills many beneficial insects too …Alternatives to Pesticides and HerbicidesPesticides are best for pestsBiological ControlUses biological predators to control pestse.g. Ladybugse.g. Wasps help to control pests in the environmentIntegrated Pest Management (IPM)Developed and under-developed worldsUse Biological Controls & Pesticides as well as Altered Management Techniques etc..Goal is Management of Pests, not EradicationSpreading fast Globally, leading to production increasesOrganic AgricultureProduced without Pesticides, Herbicides or HormonesUsually Expensive!(6) Air Pollution & Green House GasesFossil Fuel Use, LivestockAgriculture produces 9% of CO2, 37% of CH4 emissionsMethane is a potent green house gasses7. Strategies to counter the Env. Impacts of Agriculture***see above #6Some Strategies to Mitigate Soil ErosionContour PlowingStrip Cropping – mixing different crops with one anotherTechnique used to reduce soil erosionTerracing – traditional techniqueNot used in N. AmericaRiparian BuffersNo-Till AgricultureStems and roots are left to bold soil and help replenish fertilityNo-Till Increasing 7% (1991)  30% (2001)8. Trophic Argument for VegetarianismEach time you go up one level, you are only transferring 10% of the energy because of cellular respiration.We should be primary consumers. If we are on the 2nd tropic level, there is less energy loss and