Richard Wall Flashcards
why do grass eating animals have to migrate
most of grass biomass is underground. hunter gatherers followed migrations before domestication began,
when and where did domestication begin
11000-9000 ya.
irag/iran - mesopotamia, and Indus valley.
occurred when herd sizes increased to the point where nomadism was unsustainable so settled and animals husbandary and crop production was better.
which animals were domesticated?
earliest - sheep, derived from mouflon, Ovis gmelini.
Goats - analysis of mtDNA shows domestications of goat thought to have been in middle east 10,000 ya from a handful of animals.
Cattle - 1000 years later, Auroch ancestor
which communities domesticated pigs?
pigs - dont migrate, domesticated middle east, higher quality diet and shade needed.
sedentary communities, in SE asia, china, polynesia and N Europe.
today, people with ancestry from these regions have tolerance to lactose, due to dairying tradition, and milk based pastoralism.
why are there still some nomadic communities
in sub saharan africa, north america, arctic scandinavia
pop size never reached limits of sustainability, or the environment cannot support agriculture.
how much land and water does livestock take up today?
30% of the worlds surface
70% of agricultural land
8% of human water use
world wide, what benefits do livestock bring?
- crucial food resource in the case of crop failure (insurance against hard times e.g. drought)
- Provides livelihoods for 800 million poor small-holders
- Accounts for 40% of agricultural GDP
- Allows production of food from land that would be unsuitable for crop production.
what are the expected changes in the near future
global pop exp to reach 8.1 - 10.6 billion by 2050.
Meat demand per capita is exp to increase by 13% in developing nations btw 2008–2017 and double by 2050. meat demand increases with growing affluence and education.
how is livestock efficiency measured?
how many kilos of plant material used to create1kg meat.
which are the most and least efficient livestock products?
cow and goats milk is v efficient - 1.04 kg plant material needed to male 1kg milk
sheep meat and beef least efficient, 10kg plant material needed.
current estimated for aount of grain used to feed livestock?
Globally, 600 million tonnes of grain.
400m tonnes could be eaten by humans.
6 characteristics of nomadic food production
Low inputs low outputs marginal habitats extensive vulnerable to changes in water and foraging availability. Subsistence farming
4 characteristics of extensive farming
Pasture grazed but may be housed and fed in winter
Medium inputs,
High outputs,
Commercial farmers
7 characteristics of intensive farming
High inputs, High outputs, Max cost effectiveness Housed or feedlot Easier disease control Reduces land requirements High set up costs,
describe feedlot production systems
intensive production, animals outside in a small area or permanently housed, with high quality cereal feed, 2/3 of which could be fed to humans. often heavily medicated.
how is environmental change affecting livestock production?
- 20% of the world’s pastures are degraded through overgrazing, compaction, and erosion.
- damaged through overgrazing, and deforestation
how does livestock production contribute to GH gas emissions?
contributes 18% of the planet’s greenhouse-gas emissions
CO2 released in forest removal for pasture or to grow feed
poorly managed slurry and manure release nitrous oxide and methane
beef cattle emit 18-66 kg of methane per year
(plants produce 17% of current methane emissions, esp rice, so stopping livestock production would not remove 18%)
what is estimated water use to produce 1kg beef?
very high estimates, 100,000 litres water.
This would mean that a cow drinks 50-100 litres a day, unlikely.
most of the water is used for irrigtion of feed crops, so probably more like 400l per kilo of beef.
what are 3 conflicts between humans and livestack and wildlife?
- space
- water/forage
- pests and zoonotic disease
how many people are affected by zoonotic diseases from agriculture
zoonoticdiseases which emerge from agricultural systems affect millions of people.
kills 1 in 10 people who live in least developed countries.
what is rinderpest?
Cattle plague
viral disease of even toed ungulates
origin in asia, spreasd through transport of cattle. high mortality of cattle, 100% in immunologically naive pops.
tried to develop vaccine then was declared eradicated.1970s.
how can spread of zoonotic diseases be prevented.
separating cattle and wildlife.
eg. The Makgadikgadi/Boteti fence – in north west Botswana. Bashed down by elephants.
what happened in india 1990sand effect on zoonotic disease
in india, 1990s, pop crashes of White backed, long billed and slender billed vultures. White backed fell to 0.1% of population in early 1990s.
Cascading effect - no scavengers to eat fallen cows, number of feral dogs increased, and incidents of human disease.
what caused vulture deaths in india?
due to use of diclofenac to treat inflammation in livestock. vultures eating carcass of treated cattle, get acute kidney failure and die in a few days.
diclofenac banned in 2006 but remains heavily used.
how is vulnerability of communities to environmental change measured?
Vulnerability = Sensitivity + exposure – adaptive capacity
Sensitivity: nutritional reliance on local animal products and level of food security.
Exposure: impact of future climate change based on the current population % affected by drought, flooding and extreme weather and projected population growth of nations.
Adaptive capacity: nation’s ability to change or cope with changes in climate/food demand based on health, economic and governance indicators.
which are the most vulnerable nations to the impacts of population growth and climate change
many african countries, mongolia, bolivia, pakistan.
