Single Species Population II Flashcards
When would you use a discrete time model?
modelling populations that have single, discrete reproductive events each year. Eg. wildebeests
When would you use a continuous time model?
modelling bacterial populations since they divide continually (birth and deaths are at different times - see 15:04 for understanding)
What is a life history trait?
a characteristic of a species that affects in demography/population dynamic
What would the axis of a graph be if i could predict R and K from it?
Y = per capita growth rate X = Nt or N depending on if dicrete or continuous model is being used
What is r
a life history trait
births - deaths
What type of things influence r? (5)
since r is births - deaths, it’s anything that influences the number of births or deaths.
- typical no. offspring per clutch
- no. clutches per year
- mortality rate through reproductive life
- age at first reproduction
- reproductive lifespan
k is not a life history trait, so what is it?
a property of the environment that the species is living in (max number of individuals the environment can support)
Purpose of toy models
to explore the logical consequences of assumptions
Three distributions in the Mbiol course
Poisson distribution
Normal distribution
Binomial distribution
Demographic stochasticity
random fluctuations in population size that occur because the birth and death of each individual is a discrete and probabilistic event
Why are small populations in trouble? (4)
- demographic stochasticity
- environmental stochasticity
- genetic issues such as drift
- potential Allee effect
