APES Chapter 3
Uniform
Distribution pattern in which individuals are evenly spaced (as when individuals hold territories or otherwise compete for space
Random
Distribution pattern in which individuals are located haphazardly in space in no particular pattern after needed resources are spread throughout an area and other organisms do not strongly influence where individual settle
Clumped
Distribution pattern in which organisms arrange themselves in patches, generally in accordance to the availability of the resources they need
Can you think of examples of both K and R selected species not mentioned in this chapter
K selected species - elephant, whale cow, human R selected species - see turtles, snakes, most insects, caterpillars
Explain the difference between K-selected species and R-selected species
A K-selected species takes more time raising its young, often having smaller litters, and are selected species has many offspring at once, often not taking care of them after birth
Density dependent factor
A limiting factor who's affects on a population increase or decrease depending on the population density
Density independent factors
A limiting factor who's effects on a population are constant regardless of population density
Limiting factors
A physical, chemical or biological characteristic of the environment that restrains population growth
Logistic growth curve
A plot that shows how the initial exponential growth of a population is slowed and finally brought to a standstill by limiting factors
Can a species undergo exponential growth forever? Explain your answer
A species cannot undergo exponential growth forever because eventually the environment Will reach carrying capacity and no longer be able to sustain that many organisms
Emigration
Departure of individuals from a population
List and describe each of the five major population characteristics discussed in this chapter. Explain how each shapes population dynamics
Population size- providing protection or specific breeding needs, example: the passenger pigeon Population density - large organisms have lower pop density, high population density makes it easier for organisms to group and find mates Population distribution - random, uniform and clumped, layout of the species Sex ratio - proportion of males to females, indicating whether the population will increase or decrease in size over time Age structure - relative numbers of organisms in each age group, indicates whether population will grow or shrink overtime Birth and death rates- population is growing or shrinking
R-selected
Term denoting a species with high biotic potential whose members pretty said large number of offspring in a relatively short time but do not care for their young after birth. Populations of our selected species are generally regulated by density independent factors.
K-selected
Term denoting a species with low biotic potential whose members produce a small number of offspring and take a long time to just date and raise their young, but invest heavily in promoting the survival and growth of those few offspring. Populations of K selected species are generally regulated by density dependent factors.
Immigration
The arrival of individuals from an outside population
Describe how limiting factors relate to carrying capacity
The limiting resources that an organism requires but that are not in enough abundance, eventually there will not be enough of these resources to sustain a growing number of species, establishes the carrying capacity
Carrying capacity
The maximum population size that an environment can sustain
Population density
The number of individuals within a population per unit area, compare to population size