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____ is a group of similar looking organisms that interbreed in nature and produce viable fertile off spring
_____ is a group of individuals of the same species living in an area
_____is a group of populations of different species in an area
movement of individuals away from centers of high population density or from their area of origin
factors to life history
-The age at which reproduction begins
-How often the organism reproduces
-How many offspring are produced during each reproductive cycle
Life history traits are what?
Where are they reflected in?
Life history traits are evolutionary outcomes reflected in the development, physiology, and behavior of an organism
Highly variable or unpredictable environments : favor which kind of reproduction?
big-bang reproduction : semelparity
dependable environments may favor repeated reproduction : favor which kind of reproduction?
favor repeated reproduction : iteroparity
Organisms sometimes have finite resources what could this lead to?
Trade offs between survival & reproduction
K-selection, or density-dependent selection
, selects for life history traits that are sensitive to population density
r-selection, or density-independent selection,
selects for life history traits that maximize reproduction
In density-dependent populations, birth rates fall or rise? death rates? with population density
birth rates fall / death rates rise with population density
In density-independent populations, birth rates fall or rise? death rates? with population density
birth rate and death rate do not change with population density
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