1. The number of _____________ per unit area
Chapter 4
Population Ecology
4.1 Population Dynamics
Population Density
The number of _____________ per unit area
# of Organisms
Square miles
Spatial Distribution
_______________ is the pattern of spacing of a population.

2. Chapter 4
Population Ecology
4.1 Population Dynamics
Population Ranges
The area a species lives in that is limited by the _____________________ in the surrounding area.
Common dolphin
Pupfish

3. Density-Independent Factors
Chapter 4
Population Ecology
4.1 Population Dynamics – Reducing Factors
Density-Independent Factors
___________depend on the number of members in a population per unit area
Weather events
Fire
Human alterations of the landscape
Air, land, and water pollution

4. Density-Dependent Factors
Chapter 4
Population Ecology
4.1 Population Dynamics – Reducing Factors
Density-Dependent Factors
_____________on the number of members in a population per unit
Biotic factors We will do this in class
Disease
Population Biology
Competition
Parasites

5. Population Growth Rate
Chapter 4
Population Ecology
4.1 Population Dynamics
Population Growth Rate
The population growth rate (PGR) explains how ________ a given population grows.
The natality of a population is the ________ in a given time period.

6. Exponential Growth Model
Chapter 4
Population Ecology
4.1 Population Dynamics
Exponential Growth Model
Exponential growth occurs and produces a growth rate chart that looks like a ____.
All populations grow exponentially until
some ____________ slows the population’s
growth.

7. Chapter 4
Population Ecology
4.1 Population Dynamics
Logistic Growth Model
The population’s growth slows or stops following ___________growth, at the population’s carrying capacity.
Exponential Growth

8. Chapter 4
Population Ecology
4.1 Population Dynamics
A population stops increasing when the number of births is less than the number of deaths or when _____________ (moving away) exceeds _____________ (moving in).

9. Chapter 4
Population Ecology
4.1 Population Dynamics
Carrying Capacity
The maximum number of individuals of a species an environment can support for the long term is the ____________________.
Carrying capacity is limited by the energy, water, oxygen, and nutrients available.

10. Reproductive Patterns
Chapter 4
Population Ecology
4.1 Population Dynamics
Reproductive Patterns
Species of organisms vary in:
1. the number of births per reproduction cycle
2. the age that reproduction begins
3. the life span of the organism

11. 4.2 Human Population Human Population Growth
Chapter 4
Population Ecology
4.2 Human Population
Human Population Growth
The study of human population size, density, distribution, movement, and birth and death rates is demography.

12. Technological Advances
Chapter 4
Population Ecology
4.2 Human Population
Technological Advances
For thousands of years, the size of the human population remained at a relatively constant number below the environment’s carrying capacity.
Humans are now able to alter the environment in ways that have changed its carrying capacity.

13. Human Population Growth Rate
Chapter 4
Population Ecology
4.2 Human Population
Human Population Growth Rate
Although still growing, the rate has slowed.

14. Trends in Human Population Growth
Chapter 4
Population Ecology
4.2 Human Population
Trends in Human Population Growth
Human population
growth is not the same in all countries.

15. Zero Population Growth
Chapter 4
Population Ecology
4.2 Human Population
Zero Population Growth
Zero population growth (ZPG) occurs when the birthrate equals the death rate.
Eventually pre-reproductive, reproductive, and post-reproductive ages should be approximately equal.

16. pre-reproductive stage, reproductive stage, and post-
Chapter 4
Population Ecology
4.2 Human Population
Age Structure
A population’s ______________________ is the number of males and females in each of three age groups:
pre-reproductive stage, reproductive stage, and post-
reproductive stage.

17. Human Carrying Capacity
Chapter 4
Population Ecology
4.2 Human Population
Human Carrying Capacity
Scientists are concerned about the human population ___________________the carrying capacity.
An important factor is the amount of __________ from the biosphere that are used by each person.