BIOL 313 Ch 3 Factors Affecting World Agriculture
Adaptation
Definition: Adjustments in an organism promoting welfare and survival in a specific environment.
Domestic animals have a symbiotic relationship with humans, affecting global distribution.
Natural Stresses for Livestock
Climatic stress: Temperature, Rain, Solar radiation, Wind, Humidity.
Nutritional stress: Quality/quantity of food, affected by climate, soil.
Internal stress: Pathogens and toxins.
Geographical stress: Altitude, terrain, constant snow, sand, wet areas, steep rocks.
Social stress: Interactions with other animals (competition, predator-prey) and humans.
Artificial Stresses for Livestock
Artificial environments can offer protection or increase disease risk (e.g., overcrowding).
Breeds adapted to artificial environments (e.g., Holstein with 80 lbs milk/day) perform poorly in suboptimal conditions (6 lbs/day).
Adaptive changes in Livestock
Types: Morphological, Physiological, Behavioral.
All domestic animals show reduced response to environmental change.
Morphological Changes
External visible changes: color, horns, hair.
Physiological Changes
Internal biochemistry, blood chemistry.
Example: Brahman cattle (water conservation, fat hump, pendulous ears).
Behavioral Changes
Genetic or learned: self-protection, food/water seeking.
Instinct vs. learned behavior varies (poultry more instinct than pigs).
Key adaptation: reduced response to change in domesticated animals.
World Climatic Environments
Tropical: Main variation is rainfall (rainy/dry seasons). Challenges: heat stress, disease, parasites. Nomadism for forage.
Deserts: Lack of water, heat stress. Overgrazing risk.
Cold: Cold stress, food availability.
Temperate: World's most productive agricultural areas.
Social & Cultural differences in Agriculture
Culture heavily influences diet and animal production, evolving with economic situations.
Meat eating is common in wealthy Western societies, less so in poorer countries.
Religion’s effects on Agriculture
Islam and Judaism forbid pork, impacting pig populations.
Kosher production reflects religious principles and food safety.
Cattle in India vs. China
Historically, both raised cattle for food.
In India, cattle became sacred due to their importance for milk and draft, preventing slaughter.
In China, pork often replaced beef; pigs didn't thrive in India.
Levels of Economic Development
Developed countries: Robust market economies.
Developing countries: More subsistence economies, but growing.
Levels of Agricultural Development
Developed: Small proportion of farmers (<2\% in US), specialized, mechanized, high income/literacy/productivity.
Subsistence: Half the population are farmers, family farms produce little surplus, low mechanization/literacy.
Primitive: Almost everyone is a farmer, food scarce, low productivity, hand labor, illiteracy is a major barrier to new tech.
Economic Institutions and Agriculture
Financial institutions: Provide loans, store capital.
Marketing agencies: Help farmers with sales.
Industrial institutions: Create non-farm jobs, consumer goods.
Government agencies: Provide infrastructure, protection, education, land policy, sound money.