Essential Idea:
Dynamic biological processes impact
population density and population growth
Understandings:
- Sampling techniques are used to estimate population size
- The exponential growth pattern occurs in an ideal, unlimited environment
- Population growth slows as the population reaches the carrying capacity of the environment
- The phases shown in the sigmoid curve can be explained by relative rates of natality, mortality, immigraton and emigration
- Limiting factors can be top down or bottom up
Applications:
- Evaluating the methods used to estimate the size of commercial stock of marine resources
- Use of the capture-mark-release-recapture method to estimate the population size of an animal species
- Discussion of the effect of natality, mortality, immigration and emigration on population size
- Analysis of the effect of population size, age and reproductive status on sustainable fishing practices
- Bottom-up control of algal blooms by shortage of nutrients and top-down control by herbivory
Skills:
- Modelling the growth curve using a simple organism such as yeast or species of Lemna