Population Ecology Notes

POPULATION ECOLOGY NOTES

______are scientists who study population growth. When studying population growth, you will often refer to ______and ______. The following graphs and charts display ______of population growth.

I.  ______Growth – In other words, growth in a straight line. Your hourly wage would grow ______.

Example:

II.  ______or S-Shaped Growth Curve – Most populations grow this way!!

Example:

Point A: ____ Phase à Many organisms are reproducing and the

population is just getting ______.

Point B: ______Growth à The numbers of organisms are

increasing ______because there are good environmental

conditions, enough _____ & ______and few ______.

Point C: ______à (represented by the letter K) the

maximum number of organisms the ______can

support.

·  This population has reached ______because of two types of limiting factors….

o  Density-______Factors: factors that ______the population size because there are ______organisms. Examples are: ______, ______, and ______

o  Density-______Factors: factors that ______the population size ______of the number of organisms. Examples are: ______, ______, & ______.

Point D: ______Phase à The population levels out and will ______at or below the carrying capacity.

III.  Other Factors that Limit the Population Size are: ______, ______, and ______.

A.  Predation: Predatory-______Relationships are important for the health of natural populations. Usually in ______populations, the young, ______, or ______members are caught by predators.

Watch what happens in the graph below:

B.  Competition: When the population number increase in an area, ______increases until eventually the ______is greater than the ______and the population size will reach its ______and the population will stabilize.

C.  Crowding/Stress: Crowding of organisms can cause stress-related effects such as ______, ______, ______, and other odd behaviors.

IV.  Human Population: The human population has been growing ______over the past 100 or so years. This is because of the introduction of ______, ______, and ______.

Age structure

Relative number of individuals of each age

What do these data imply about population growth in these countries?