Chapter 36: Population Ecology Flashcards
Population Ecology
The study of how members of a population interact with their environment,focusing on factors that influence population density and growth
What do population ecologists study
the interactions between biotic and abiotic factors that cause variation in population dynamics
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
What does the data from a life table help with
Data helps develop effective measures for maintaining a viable population
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
isnt that crazy bro
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
Survivorship Curve ~ Type III
many births and many deaths
What are some examples of organisms that follow Survivorship Curve ~ Type III
fish and plants
In Survivorship Curve ~ Type I organisms produce _____ offspring but give them _____ care
few; good
In Survivorship Curve ~ Type III organisms produce _____ numbers of offspring and provide ____ care
large, little to no
True or False
Organisms follow the different types of survivorship curves exactly
False
Exponential Growth
the growth rate increases as the population increases
What is exponential growth caused by
unlimited resources, no predators, large area of land/space, no disease/natural disasters
Exponential Growth Model
an idealized picture of unlimited population growth
The slope of an exponential growth model becomes _____ as population increase
steeper