Ecology POPULATIONS vocab Flashcards
biotic
living organism
ecology
the scientific study of the interactions between organisms and the environment
abiotic
nonliving
hierarchy
organism –> population –> community –> ecosystem –> landscape –> biosphere
population
a group of individuals of the same species living in the same general area
community
a group of populations of different species in an area
ecosystem
community of organisms + physical factors
population ecology
explores how biotic and abiotic factors influence density, distribution, and size of populations
community ecology
how interactions between different species affect community organization
ecosystem ecology
emphasizes energy flow and chemical cycling between organisms and the environment, takes living and nonliving components into consideration
global ecology
examines how regional exchanges of energy and what materials influence the functioning and distribution of organisms across the biosphere
where species occur acrosss the biosphere (distribution) is influenced by
climate; biotic factors
population density
of individuals / area ;
population dispersion
pattern of spacing between individuals
population size is determined by
birth, death, migration
clumped pattern
near required resource; increases effectiveness of predation/attack; spread in patches; may be associated with breeding, location of food, mating
uniform pattern
result of antagonistic interactions; evenly spaces; uncommon; compete for resources
random pattern
unpredictable spacing; uncommon; occurs in absence of strong attractions; plants distributed by wind blown seeds
demography
study of vital statistics of populations and how they change over timel
life table
age specific summary of the survival pattern of a population
type I curve
low death rate in early life ; humans, large mammals
type II curve
constant death rate over lifespan (straight line; plants, invertebrates)
type III
high death rate early in life (associated with organisms that produce large # of offspring but provide little to no care)
change in population size formula
dN/dt = B - D