1. Ecology of Populations
Chapter 46
Mader: Biology 8th Ed.

2. Population Density and Distribution Population Growth Models
Outline
Scope of Ecology
Population Density and Distribution
Population Growth Models
Survivorship Curves
Age Distributions
Regulation of Population Size
Life History Patterns
Human Population Growth
Environmental Impact
Mader: Biology 8th Ed.

3. Habitat - Place where an organism lives.
Scope of Ecology
Ecology - Study of the interactions of organisms with other organisms and the physical environment.
Habitat - Place where an organism lives.
Population - All the organisms within an area belonging to the same species.
Community - All various populations interacting at same locale.
Ecosystem - Community of populations.
Mader: Biology 8th Ed.

4. Ecological Levels
Mader: Biology 8th Ed.

5. Density and Distribution of Populations
Population Density - Number of individuals per unit area or volume.
Population Distribution - Pattern of dispersal of individuals within the area of interest.
Ecologists want to analyze and discover what causes the spatial and temporal “patchiness” of organisms.
Limiting Factors are factors that particularly determine whether an organism lives in an area.
Mader: Biology 8th Ed.

6. Uniform Distribution
Mader: Biology 8th Ed.

7. Random Distribution
Mader: Biology 8th Ed.

8. Clumped Distribution
Mader: Biology 8th Ed.

9. Characteristics of Populations
Intrinsic Rate of Natural Increase (r)
If immigration (+) and emigration (-) cancel each other out, then population growth can simply be modeled by birth rate minus the death rate.
Mader: Biology 8th Ed.

10. Population Growth Models
Exponential Growth
Number of individuals added each generation increases as the total number of females increases.
Biotic Potential - Maximum population growth that can possibly occur under ideal circumstances.
Environmental Resistance - All environmental conditions that prevent populations from achieving biotic potential.
Mader: Biology 8th Ed.

11. Exponential Growth Curve
Mader: Biology 8th Ed.

12. Exponential Growth Equation
Mader: Biology 8th Ed.

13. Logistic Growth
Logistic growth occurs when environmental resistance comes into play and retards exponential growth.
Living populations must eventually come under the control of environmental resistance.
Mader: Biology 8th Ed.

14. Logistic Growth
Mader: Biology 8th Ed.

15. Logistic Growth
Mader: Biology 8th Ed.

16. Carrying Capacity
Carrying Capacity is the maximum number of individuals of a given species the environment can support.
The closer the population to the carrying capacity, the greater the environmental resistance.
Biotic potential is having full effect and birthrate is a maximum during exponential growth.
Mader: Biology 8th Ed.

17. Mortality Patterns
A cohort is composed of all the members of a population born at the same time.
Survivorship is the probability of newborn individuals of a cohort surviving to particular ages.
Survivorship Curves
Mader: Biology 8th Ed.

18. Survivorship Curves
Mader: Biology 8th Ed.

19. Survivorship Curves
Mader: Biology 8th Ed.

20. At least three structures possible. Increasing Stable Decreasing
Age Distributions
Populations differ according to what proportion of the population falls in each age category.
At least three structures possible.
Increasing
Stable
Decreasing
Mader: Biology 8th Ed.

21. U.S. Age Distributions
Mader: Biology 8th Ed.

22. Regulation of Population Size
Density - Dependent Factors
Number of organisms present influences the effect of the factor.
Competition
Predation
Density - Independent Factors
Number of organisms present does not influence the effect of the factor.
Natural Disasters
Mader: Biology 8th Ed.

23. r - Strategists (Opportunistic) Produce large numbers of offspring.
Life History Patterns
r - Strategists (Opportunistic)
Produce large numbers of offspring.
Small body size.
Early maturity
No parental care.
Density independent controls.
Good dispersers and colonizers.
Mader: Biology 8th Ed.

24. k - Strategists (Equilibrium) Produce small numbers of offspring.
Life History Patterns
k - Strategists (Equilibrium)
Produce small numbers of offspring.
Large body size.
Late maturity
Significant parental care.
Density dependent controls.
Specialists
Mader: Biology 8th Ed.

25. Human Population Growth
Human population has an exponential growth pattern.
Doubling time currently estimated at 53 years.
Population Size
Billion
Billion
Billion
Billion
Mader: Biology 8th Ed.

26. World Population Growth
Mader: Biology 8th Ed.

27. More-Developed Countries (MDCs) Slow population growth.
Country Development
More-Developed Countries (MDCs)
Slow population growth.
High standard of living.
Completed Demographic Transition.
North America and Europe
Less-Developed Countries (LDCs)
Rapid population growth.
Low standard of living.
Latin America
Africa and Asia
Mader: Biology 8th Ed.

28. Age Structure Diagrams divide populations into three age groups.
Age Distributions
Age Structure Diagrams divide populations into three age groups.
Pre-Reproductive
Reproductive
Post-Reproductive
Mader: Biology 8th Ed.

29. More-Developed Countries
Mader: Biology 8th Ed.

30. Less-Developed Countries
Mader: Biology 8th Ed.

31. Environmental impact of a population is measured in terms of:
Population Size
Resource Consumption Per Capita
Resultant Pollution
Mader: Biology 8th Ed.

32. Environmental Impact
Mader: Biology 8th Ed.

33. Population Density and Distribution Population Growth Models
Review
Scope of Ecology
Population Density and Distribution
Population Growth Models
Survivorship Curves
Age Distributions
Regulation of Population Size
Life History Patterns
Human Population Growth
Environmental Impact
Mader: Biology 8th Ed.

34. Mader: Biology 8th Ed.