8-1 How Populations Change in Size

Page 197

A. What is a population?• 1. Set of individuals within a species living in

the same place at the same time.

How many populations are in this picture?

B. Properties of Populations

• 1. Density is the number of individuals per unit area or volume.

B. Properties of Populations

• 2. Dispersion describes arrangement of individuals in a population; can be even, clumped, or random.

even, clumped, or random?

C. How Does a Population Grow?

• 1. Populations gain individuals with each birth, and lose individuals with each death.

C. How Does a Population Grow?

• 2. The % change in a population is the growth rate.

• Change in Population Size= Births- Deaths

Change in Population Size= Births- Deaths

Births Deaths Change in Population Size

5 55535 7682345 8765

D. How fast can a population grow?

• 1. The reproductive potential of a population determines the maximum # of offspring that each member can produce.

D. How fast can a population grow?

• 2. If a population experiences exponential growth, it will grow faster and faster.

E. What Limits Population Growth?

• 1. Carrying Capacity is the population size where birth and death rates are equal.

What type of growth? (Graph the Data)

Days (X) Consumption (Y)

1 102 103 204 305 40

What type of growth? (Graph the Data)

Days (X) Consumption (Y)

1 102 203 304 305 20