Term
| Demographic Stochasticity |
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Definition
In smaller groups, averages of population don't apply as much (i.e., avg pop of 2. In a group of 20 individuals, 2 is less likely to be average, more likely in 200 or 2000). Sex ration, death rate also apply |
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Term
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Definition
Small pop's may have too few to support social structures of population (herds, etc.), maybe harder to find mates.
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Term
Environmental Stochasticity |
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Definition
| Populations fluctuate over time w/ weather, seasons. If changes are predictable (nile river flood) than deterministic processes are present. If changes are unpredictable (volcano), stochastic processes are present. |
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Term
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Definition
Marked change in population from one time period to next = high variance, low variance = constant population size 很好！ |
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Definition
Smaller population increases risk of extinction- natural disaster = population decline, Inbreeding depression = young survival decline, (vicious cycle) |
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Term
| Minimum Viable Population & Society |
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Definition
| Society must determine risk and cost of MVP. Conservation biologists can suggest scenarios, but public must decide |
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Term
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Definition
Can caust genetic drift through fragmentation and isolation of sub-species. I.e., collared lizards and glade habitats of missouri. Pop's susceptible to extinction and genetic drift |
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