1. POPULATIONS- individuals of the same species that live together in the same place.

2. Population Features Size- How many of one type of organism that exist.
Density- How many of an organism that live in a given area.
Dispersion- how a certain organism is arranged in that given area.

3. Patterns of Dispersion
Clumped distribution
Even distribution
Random distribution

4. DEMOGRAPHICS – The statistical study of the characteristics and composition of the population.

5. 4 factors determining the Population
Birth rate or Natality
Emigration POPULATION Immigration
Death Rate or Mortality

6. Modeling Population Growth
A population model is a hypothetical graph used to show how a specific population could react to specific factors that are manipulated by those that make the graphs.

7. Types of Population Models
Exponential Growth Curve Model- this is a graph that shows steady growth of a population which would go unchecked.
Size x rate of growth

8. The Carrying Capacity = K
The largest population an environment can
support at any given time.

9. Populations do not go unchecked and are normally limited to the resources in a given area so populations will eventually reach their carrying capacity . This is called logistical growth because it’s logical.

10. Graphic Analysis
Mean – (The average) …the sum of the data divided by the total possible. 2,4,6,8,= mean-5
Median- This is the midpoint in a series of numbers. 1……….7………….14
Mode – The most frequently occurring value.
Range – The difference between the largest and smallest value.

11. Density Independent Factors
Environmental conditions like climate or weather that dictate the growth or decrease a population.

12. Density Dependent Factors
These are factors that are limited to an area and their amounts are dictated by the size of populations within that area. Best examples are food and water.

13. Examples of limiting factors…
Predation
Disease
Food limits
Water
Temperature
Mating availability
Shelter

14. Effects of Factors
Some organisms only thrive during certain times of the day or year because of the temperature and climate of the area. Also others can only breed when conditions are right
Dependent factors create the limiting line that makes populations have a carrying capacity. Go past that line and food runs out!

15. R strategists
These organisms breed in high numbers and create huge populations, but they don’t live long and must reproduce often.
Growing and developing is quick so these organisms are small and simple. They also drop in numbers when conditions start to worsen.

16. In past information
You could use R strategist as a good example of exponential growth, but as time continues that growth is followed by exponential death.
These organisms also has no parental involvement other than to have the offspring and have them often.

17. K-strategists
These organisms are like us. We live long lives and have few children. We care for them for long periods of time and our development is very slow. They also tend to live in stable environments. Population grows more logistically than exponentially.
                              

18. Hardy – Weinberg Principle
The frequency of alleles in a population does not change unless evolutionary forces act on the population.
** When climate changes
populations will change or adapt..***

19. Evolutionary forces acting on a Population
Mutations – changes in the genes
Non-random mating – inbreeding
Gene flow- Immigration / Emigration
Natural selection – competition /struggle
Genetic drift – Isolation of small populations
(high mortality)

20. Population Change - EVOLVE
Phenotype- physical appearance changes
Genotype- actual genes in the population change
Alleles – expression of genes– mutation
Change in DNA=mutation