Chapter 7 How to Make an Almond. Fleshy Fruits In nature, fruits are often fleshy to attract animals...

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Chapter 7

How to Make an Almond

Fleshy Fruits

• In nature, fruits are often fleshy to attract animals

• the seeds of fruit are often bitter and are dispersed (and fertilized) by passing through the animal.

• Domestication of plants by humans also may have started in such latrines.

Selection of Desired Qualities

• Eventually humans selected desired qualities:

– Size

– lack of bitterness

– fleshiness

– Oiliness

– fiber length in plants.

Traits Selected Unknowingly

• Dispersal mutations (peas that stayed in the pods, wheat that did not shatter)

• Early germination of planted seeds -- those that did not readily germinate were not selected for replanting (examples wheat, barley, peas)

• Reproductive biology to be selfing (plums, peaches apricots, cherries, grapes)

• Seed size: competition among planted seeds selects for qualities like seed size differently than in nature.

Difficulty of Domestication

• Wheat and peas easy to domesticate in Fertile Crescent (8,500 B.C.)

– grew wild

– annual

– easily stored

Difficulty of Domestication

• Fruit and nut trees harder to domesticate(4,000 B.C.) – long growing

season.

• Fruit trees that needed grafting took even longer

Pulses

• Cereals are low in protein, but the deficit is made up by pulses (beans, peas, lentils) in most food systems.

Sowing by Broadcast

• Grains in Eurasia were sown by broadcast, later in animal plowed fields to give monoculture.

Digging Sticks

• In new world, planting done by digging stick, (no plow animals domesticated), leading to mixed gardens.

Almonds and Oaks

• Almonds more easily domesticated:– faster growing– Only one gene for bitterness of seed.

• Oaks never domesticated:– slow growth– fast squirrels replant acorns– multiple genes controlling bitterness.

Chapter 8

Apples or Indians

Domesticated Plants

• There are 200,000 species of plants

• Only a dozen plants account for 80% of worlds production

80% of World’s Production:

• Wheat• Maize• Rice• Barley• Sorghum• Soybean• Potato• Cassava• Sweet potato• Sugar cane• Sugar beet• Banana

Major Domesticated Crops

• No new plants domesticated in modern times

• All of these domesticated  thousands of years ago.

Domestication Requirements

• Several domesticable plants had large ranges, but domesticated only in one place.

• Why not in others? • Domestication required

settling down, and had to be worth it with several plants domesticated, not just one.

Fertile Crescent

Fertile Crescent Attributes

• Mediterranean climate.

• Abundant wild stands of wheat that needed little change to be domesticated.

• Hunter/gatherers settled down here before agriculture, living off grain

• High percentage of self pollinating plants -- easiest to domesticate.

Fertile Crescent Advantages

• Largest Mediterranean climate with highest diversity of species.

• High percentage of annual plants. Annuals produce seeds that dry down until rainy season.

• Of large seeded grass species of the world, 32 of 56 grow here.

Fertile Crescent Advantages

• Diversity of terrain and habitats: diversity of species to be domesticated.

• Big animals for domestication: goat, sheep, pig, cow.

Fertile Crescent Domestication

• Agriculture launched by domestication of 8 crops (founder crops): emmer wheat, einkorn wheat, barley, lentil, pea, chickpea, bitter vetch, flax.

• Wheat and pulses gave balanced carbohydrate and protein.

Fertile Crescent Domestication

• Hunter gathering eventually not too productive, easily giving way to agriculture.

• Domestication occurred from 9,000 B.C. to 6,000 B.C.

Meso America

• In Meso America, the only animals domesticated were turkey and dog

• Maize was slow to domesticate.

• Domestication occurred from 3,500 B.C. to 1,500 B.C.

Independent Domestication

• In New Guinea or USA, food also independently domesticated, but limited crops.

• Indigenous peoples usually walking encyclopedias about wild foods.

Independent Domestication

• Was it culture that rejected domesticated crops?

• Unlikely since imported crops readily adapted and then populations took off.

Independent Domestication

• Problem was in the plants available for domestication.

• Poor candidates for grain domestication

• No large animal domestication,

• Crops domesticated had limited calories and protein.

New Guinea

• New Guinea crop was Taro:

• Low in protein, leading to eating of

– Spiders

– Frogs

– Mice

– Cannibalism

USA

• USA crops were squash, sunflower, sumpweed and goosefoot.

• Not enough of a crop package to sustain large populations without hunting and gathering, until Maize imported 2000 years later.

• Therefore it was the lack of an entire suite of animal and plants available for domestication that was responsible for the late start of food production in N. America.

Chapter 9

Zebras, etc

Big 5 Domesticated Animals

• Horse

• Cow

• Pig

• Sheep

• Goat

• All from Eurasia

Domesticated Animals

• Of the 14 large (over 100 lb) successful domesticated animal species in the world– 13 are from Eurasia, – one from South

America.

• Why the huge disparity?

• Why did Africa have none?

Large Animals

• Of 148 large herbivorous or omnivorous species in the world– Eurasia had 72– Africa 51– Americas 24– Australia 1

Not a Cultural Issue

• When the big 5 Eurasian domesticates were introduced into Africa and the Americas they were readily adopted.

• All peoples have experience taming wild animals, keeping pets.

• But not all tamed animals can become domesticated.

Not a Cultural Issue

• All major animal domestication occurred between 8,500-2,500 B.C. with almost none since then.

• Those of the 148 possible species capable of being domesticated were domesticated.

Why have 134 out of 148 big species not been domesticated?

• Diet too finicky (ex: koala)

• Growth rate too slow (ex: elephants, gorillas)

• Captive Breeding. Some animals have elaborate mating rituals that they won't do in captivity (ex: cheetah, vicuna)

Why have 134 out of 148 big species not been domesticated?

• Nasty Disposition. (ex: grizzly bear, African buffalo, onager, zebra, hippo, elk)

• Tendency to panic. (ex: deer, antelope, gazelles).

Why have 134 out of 148 big species not been domesticated?

• Social structure. – Need animals that live in

herds with hierarchy and have overlapping ranges

– Humans can then take over dominance position.

– Solitary animals hard to domesticate (only cats and ferrets have been).

Why have 134 out of 148 big species not been domesticated?

• Territorial animals hard to pen up with others (ex: Africa antelope, rhino).

• Animals without dominance structure are hard to herd (ex: deer, antelope.

Chapter 10

Spacious Skies and Tilted Axes

Easier to spread East-West

• It was easier for domestic plants and animals (later, technology like wheels, writing) to spread East-West in Eurasia than North- South in Americas.

Evidence

• Some crops domesticated independently in both S. America and Meso America due to slow spread– lima beans

– common beans

– chili peppers

Evidence

• Most crops in Eurasia domesticated only once.

• Rapid spread preempted same or similar domestication.

• Fertile Crescent crops spread to Egypt, N. Africa, Europe, India and eventually to China.

Africa

• East-West spread of plants, animals easier due to same day-length, similar seasonal variations.

• By contrast, spread of these crops stopped past Sahara due to tropical climate, and thus didn't reach temperate S. Africa until colonists came.

• Tropical crops spread West to East in Africa with Bantu culture, but did not cross to S. Africa due to climate.

Americas

• Distance between cool highlands of Mexico and Andes was only 1,200 miles but separated by low hot tropical region.

• Thus, no exchange of crops, animals, writing, wheel. – Only maize spread.

Americas

• It took 2,000 years for maize to cross 700 miles of desert to reach U.S.A.

• It took another 1000 years for maize to adapt to U.S.A. climate to be productive

Amber Waves of Grain

• Geographic barriers like mountains and deserts can also slow spread of crops East-West – agriculture spread from U.S.A.

southeast to southwest slowed by dry Texas and southern great plains

• Amber waves of grain did not stretch from sea to sea in N. America, but did in Eurasia.

Not a Cultural Issue

• Some species like cows, dogs, pigs independently domesticated in different parts of the world. These animals were well suited for domestication.

• Modern attempts to domesticate eland, elk, moose, musk ox, zebra, American Bison are only marginally successful.

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