Populations and Communities
Define Biotic Potential
the maximum rate in which a population can increase
List and describe the 4 stages of the demographic transition model
•Preindustrial: Birth and death rates are both high
•Transitional: Death rate declines; birth rate remains high
•Industrial: Birth rate declines
•Postindustrial: Negative growth rate
define species richness
the number of species present
Define Resource Partitioning
the division of resources to avoid interspecific competition for limited resources in an ecosystem
define herbivory
a species which consumes plants
List the environmental resistance factors
depends on food, space, and interactions
A situation in which the birth rate equals the death rate is called
zero population growth
define niche
The total of all factors in an organism’s environment
Space
Food
Climate
Temperature
Moisture
Define Intraspecific Competition
competition between members of the same species
The earthquake that devastated the population of Haiti in January 2010 could be described as a ____ factor, while water and food shortages that caused disease and death in the aftermath among quake survivors could be described as
density independent; density dependent
List the 4 revolutions which have affected how human populations are changing
Cultural Revolution - Hunting and Gathering
Agricultural Revolution
Industrial / Medical Revolution
Green Revolution
define resource partitioning
The evolutionary process by which species become adapted to use a shared limiting resource in a way that minimizes competition
List the 5 factors which limit life
Temperature
Light
Oxygen
Carbon dioxide
Precipitation
What is coevolution
the influence of closely associated species on each other in their evolution
The age structure diagram for rapidly growing populations ____.
is in the form of a pyramid and has a very broad base showing a large number of young
What are the 3 most populous countries
China, India, U.S.
Species richness is generally higher on larger islands because ____.
more colonists from mainland areas will happen upon a larger island because of its size, bigger islands offer a wider variety of different habitats, and larger islands can support larger populations of species than smaller islands
Define Interspecific competition
competition among members of different species
each species occupies the same ecological niche
Define mimicry
when a a non threatening species copies the appearance of a threatening species to ward off predators
Eight species of woodpeckers coexist in Oregon forests. All feed on insects and nest in hollow trees, but the details of their foraging behavior and nesting preferences vary. What does this best illustrate?
resource partitioning
define the demographic transition model
describes population growth rate changes over time as a country becomes economically developed
Snowshoe hares are brown for part of the year and turn white in winter, making it harder for predators to spot them. This is an example of ____.
camouflage
Define competitive exclusion
If two species are competing for a limited resource, one will eliminate the other
List the 5 trophic levels and what they consist of
Producers - autotrophs
Primary consumers - herbivores and decomposers
Secondary consumers - carnivores, omnivores, and decomposers
Tertiary consumers - carnivores, omnivores, and decomposers
what is a cohort
group of individuals of the same species born during the same time interval