Chapter 36: Population Ecology Flashcards
Population Ecology
The study of how members of a population interact with their environment
Population Density
the number of organisms that exist in a given area
Dispersion
how the organisms in a population are spread out in a given area
How many types of dispersion are there
3
What are the 3 types of dispersion
1) Clumping Dispersion Pattern
2) Uniform Dispersion Pattern
3) Random Dispersion Pattern
Clumping Dispersion Pattern:
when organisms are located extremely close together/ in the same portion of an area
Uniform Dispersion Pattern:
organisms are spread out somewhat evenly
What causes clumping
resources in one area, body heat, safety/protection from predators, society and family units, to get prey more successfully
What is an example of clumping
ants in an ant colony
What is the most common type of dispersion
clumping
What causes Uniform Dispersion Pattern
territorial behavior, organisms need a certain amount of space to grow
What are some examples of organisms that might follow uniform dispersion pattern
birds - nest uniformly because they each need space to teach their young how to fly, etc.
trees - need roots to grow
Random Dispersion is caused by
resources available everywhere (fertile soil everywhere, or sun reaching everywhere[for photosynthesis] )
What is the rarest dispersion pattern
random dispersion pattern
Life Table
a table that monitors the chance of survival/death (survivorship) of organisms in different age groups in a certain cohort of a population
cohort
a group of organisms in a population that are used in a life table
What does the data from a life table help construct
survivorship curves
Survivorship Curve
plot survivorship as the proportion of individuals from an initial population that are alive at each age
How many types of survivorship curves are there
3
What are the 3 types of survivorship curves
1) Type I
2) Type II
3) Type III
Survivorship Curve ~ Type I
organisms in a population live for a relatively long time but begin to die at a certain age
What are some examples of organisms that follow Survivorship Curve ~ Type I
humans and other mammals
Survivorship Curve ~ Type II
survivorship curve is the same for the entire life of the organism; so the organisms have equal amount of chance to live and die at any age range
What are some examples of organisms that follows the Survivorship Curve ~ Type II
invertebrates, lizards, rodents, squirrels