Concepts 15.1-15.3 Flashcards
What is a population model?
Mathematical models that estimate change in population size over time
How does exponential growth occur?
When populations are not limited by resources
How does exponential growth occur?
When population growth is limited by resources. i.e. reaches its carrying capacity
What does R stand for in population growth?
Growth rate
What do different values of R indicate?
R>1 population increases indefinitely
R<1 Population decreases over time
R = 1 Population remains stable
What are some density-dependent factors?
Competition for resources, predations, disease
What are some density-independent factors?
Heat waves, storm events, pollution
What are density-dependent factors?
Factors that change population growth depending on the number of individuals in the population
What is environmental stochasticity?
Unpredictable fluctuations in environmental conditions
What is demographic stochasicity?
Change in birth and death of individuals caused by chance
What is a metapopulation?
A group of geographically isolated populations linked together by dispersal
What is a source population?
Support local population growth and can be net exporters of individuals (emigration) to other patches
What is a sink population?
Mortality exceeds births and populations are reliant on immigration to persist
What is colonisation rate?
The proportion of unoccupied sites that become occupied per unit time
What is extinction rate?
The proportion of occupied sites that go extinct per unit time
