Chapter 52.1 and 53

• -Something that occurs over many generations.
• -Ex: Organisms adapt to their evnrionment over many generations through the process of natural selection; this adaptation occurs in the time frame of evolutionary time.

• -The minute to minute time fram of interactions between organism and the environment.
• -Ex: The differential survival and reproduction of individuals that lead to evolution occurs in ecological time.

Advocating the protection of nature.

The study between the interaction of organisms and their environment.

• -The study of populations with relation to their environment.
• -Ex: Studying a sheep's population ecology because their population changes drastically from year to year.

• -Ecologists begin investigation a population by defining the boundaries
• -The boundaries are limited to the organism under study and the question being asked.
• -May be naturally defined by nature or arbitarily defined by the investigator

-The number of organisms per unit area or volume.

• -Counting, but sometimes that can be impractical.
• -Countin a certain X by X and multiplying that by the amount of plots there are.
• -Estimating density from an index of population size (number of nests, droppings)
• -Mark-Recapture Method.

• -Capture a population, mark them, release, wait to mix back into population
• -Capture a second population, mark them and release, wait to mix back into population.
• -The estimated population size is the number in the first sample, multiplied the number of individuals recaptured, and then divided by the the number marked in the second sample.

• Immigration: The influx of individuals from other areas.
• Emmigration: The number of influx out of a population.
• -Both influence the population density of their population as well as others' population.

Variations in local density provide insight into the environmental associations and social interactions of individuals in the populations.