population distributions Flashcards
spatial structure
the pattern of density and spacing of individuals in a population
fundamental niche
the range of abiotic conditions under which a species can persist
-includes the range of temperature, humidity, and salinity conditions that allow a population to grow, survive, and reproduce
realized niche
the range of abiotic and biotic conditions under which a species does persist
-determines the geographic range of populations that compose a species
geographic range
a measure of the total area covered by a population
ecological niche modeling
the process of determining suitable habitat
-can help predict probability of successful reintroductions for nearly extinct species, the area where new pests might spread after introduction
-challenging when few individuals living in the wild
ecological envelope
the range of ecological conditions that are predicted to be suitable for a species from ecological niche modeling
-similar to the realized niche but is a predictions of where a species could POTENTIALLY live
an cause a shift in the geographic range of species
temperature
population characteristics
-geographic range
-abundance
-density
-dispersion
-dispersal
endemic (geographic range)
species that live in a single, often isolated, location
cosmopolitan (geographic range)
species with very large geographic ranges that can span several continents
abundance
the total number of individuals in a population that exist within a defined area
- number of sunfish in a lake
density
the number of individuals per unit area or volume
-calculated by dividing abundance by area
dispersion
the spacing of individuals with respect to one another within the geographic range of a population
clustered dispersion
when individuals are aggregated in discrete groups
-clustering around resources or social groups
evenly spaced (uniform) dispersion
when each individual maintains a uniform distance between itself and its neighbors
- defended territories or croplands