Summary:
- Population growth is the change in the size of the population over time.
- An important factor in population growth is age-sex structure.
- This is the number of individuals of each sex and age in the population.
- Younger people are more likely to reproduce, while older people have higher rates of dying.
- Survorship curves reflect death rates at different ages.
- The three types of curves shown in the figure actually represent different strategies species use to adapt to their environment.
- The Type I strategy occurs more often in stable environments, while the Type III strategy is more likely in unstable environments.