OriginOfAgriculture Flashcards
Agriculture definition
- Human manipulation of plant populations and the environment as to increase yield (calories/nutrients) per unit of time and space
What did agriculture lead to?
- Development of cities and civilizations when there was food to feed concentrations of people
Cultivated plants are the result of what?
- Most cultivated plants did not exist 10,000 years ago
- Result of generations of human selection
What is Domestication?
- Evolutionary process of genetically altering plants from the wild state so that their survival is dependent upon human intervention
- Mostly by early cultivators
- Effect of modern breeding relatively less important
What does domestication require?
- Alteration of environment:
- Removing competition (weeding)
- Planting (seed or vegetative tissue)
- Irrigating
- Fertilizing
- Tilling
- Protect from frost
World food supply is based on what? How many plants species in total to how many domesticate crop plants?
- World food supply based on very few species, very little genetic diversity within those species
- 350,000 plant species (250,000 flowering plants)
- Approx. 50,000 edible
- 250-300 cultivated as food
- 22 major domesticated crop plants
How did the transition from hunting/gathering to farming occur? Rapid, or slow?
- Gradual transition with development of food processing and ‘proto-farming’ (cooking, fermentation, drying, soaking)
What is some of the first evidence for farming?
- 53,000 years ago in Borneo
- Burning forests to open habitat for edible tubers, nuts, fruits
Why did the transition to farming occur?
- No clear consensus!
- Not necessarily a result of population growth or of sedentary lifestyle as gathering can be as effiecient as cultivation
- Could be crowding caused by changing climate?
- Adoption of ‘camp followers’
- Transition did not occur as much for fishing cultures (alternate strategy)
‘Camp Followers’
- Plants that grew from dump heaps
- May have contributed to farming
How could climate change have contributed to farming?
- Crowding caused by changing climate
- Drying in near east brought people and animals together near water
- Rising sea level in SE Asia drowned ‘Sundaland’
Why did the transition to farming occur around the same time in many parts of the world?
- No clear single answer
- Changes in global climate (increased seasonality of rainfall, dry periods that favoured grasses/annuals and species w/ underground stems)
- Gradual change in social structure from nomadic to sedentary precipitated by climate change?
When did the transition to farming occur in many parts of the world?
- Approx. 10,000 years ago
Where did agriculture begin? As defined by V.I. Vavilov (map in text)
- E NA (South of Great Lakes, near Tennesse, Kentucky)
- Mesoamerica (Mexico)
- SA Highlands (Peru, Columbia, Ecuador)
- Fertile Crescent (Syria, Iran, Pakistan)
- Yangtze and Yellow River Basins
- New Guinea Highlands
For an individual crop, where is the place of domestication likely to be?
- The area of highest diversity
- Some domesticated more than once independently
What are some changes selected for in crop plants?
- Increase in size or other desired property of plant
- Loss of protective mechanisms, thorns, bitter taste
- Loss of natural dispersal (non-shattering grasses selected for collecting)
- Simultaneous ripening
How did agriculture spread?
- From places of origin through migration
- Occured faster east to west than north to south
- Influence of latitude and geography
- Agriculture increased total amount of food for humankind (pop. increase from 50million to 7.5 billion over 10,000 years)
Would farmers have had a better diet compared to forager?
- Not really, and had to work harder
Have we been domesticated by our crops? How did this also affect plants?
- Wheat, one wild grass in Middle East 10,000 years ago
- Now covers 2.25 million sq. km of world surface propagated by humans and whole agricultural industires
- But crop plants now have selected traits that make them dependent on humans (loss of natural dispersal w/ non-shattering fruit heads on grains)
- Dependent on each other for survival and prosperity
Current state of agriculture, and how much do family farms produce
- Industrialized agriculture feeds the developed world
- But family farms still produce 3/4 of world’s food
- Large farms good for huge amount of 1 crop
- Small diversified farms produce more food and more kinds per hectare overall
Urban farming: Vertical farming with aeroponics
- Growing grops, usually w/o soil or natural light in beds stacked vertically inside a controlled environment
- Water and nutrient solution supplied by spraying
- Use urban space in vertical dimension
- Another way to provide food locally
