1. KEY CONCEPT Each population has a density, a dispersion, and a reproductive strategy. What is happening in the picture?
Competition – intraspecific(same members compete) interspecific(different species compete)

2. Predation Parasitism Mutualism Commensalism
Predation – one org. captures & eats another /Mutualism – both benefit/ Commensalism-one organism benefits, the other is unharmed /Parasitism-1 benefit other harmed
Mutualism
Commensalism

3. Population density is the number of individuals that live in a defined area.
Scientists can calculate population density.
200 deer in an area 10 square kilometers
200/10 km2 = 20 deer per km2
What can scientists learn about
a habitat if they see a change in the
density of a population?

4. Population dispersion refers to how a population is spread in an area.
Geographic dispersion of a population shows how individuals in a population are spaced.
Population dispersion refers to how a population is spread in an area.
This will help scientist to understand
how species interact among
themselves and with other species.
Clumped
dispersion
Uniform
Random

5. There are three types of dispersion.
Clumped- live close together (herd,school,cluster)
helps to avoid predators
facilitates mating
access food resources.

6. There are three types of dispersion.
Uniform – individuals live specific distances apart
Territoriality
Intraspecies competition

7. There are three types of dispersion.
Random – individuals are randomly distributed
no competition and few predators

8. Survivorship curves help to describe the reproductive strategy of a species.
A survivorship curve is a diagram showing the number of surviving members over time from a measured set of births.

9. Survivorship curves can be type I, II or III.
Type I—low level of infant mortality and an older population
common to large mammals and humans (parenting)
Type II—survivorship rate is equal at all stages of life
common to birds and reptiles
Type III—very high birth rate, very high infant mortality
common to invertebrates, fish, amphibians and plants
predators