Coombs - APES Chapter 8

238907588	immigration	organisms in a population moving into an area
238907589	emigration	organisms in a population moving out of an area
238907590	age structure	proportion of individuals in a population at various age ranges
238907591	pre-reproductive	individuals not capable of reproducing
238907592	reproductive	individuals capable of reproducing
238907593	post-reproductive	individuals too old to be capable of reproducing
238907594	intrinsic rate of increase (r)	how fast a population would grow under ideal conditions with no limiting factors or environmental resistance acting upon it
238907595	environmental resistance	any factor (limiting factor) that can limit a populations growth; ex: amount of space, temperature, precipitation, disease, food availability
238907596	biotic potential	capacity for growth; how well an organism can reproduce and get offspring out into the environment; ex: high biotic potential = fish, insects, small mammals like mice, etc.; low biotic potential = large mammals like the panda, elephants, rhinos, etc.
238907597	carrying capacity (K)	maximum number of individuals an ecosystem can support for an extended period of time or indefinitely; determined by biotic potential of the organism and the environmental resistance factors that population faces
238907598	exponential growth	rapid growth; doubling of population each generation; usually associated with intrinsic rate of increase (r); happens when organisms have very little environmental resistance factors or limiting factors acting upon them
238907599	j-curve	exponential growth demonstrated by a population when it has few limiting factors or little environmental resistance acting upon it
238907600	logistic growth	rapid explosive growth followed by decrease in population growth until population levels off
238907601	s-curve	logistic growth, hovering slightly above and below the carrying capacity
238907602	overshoot	exceeding the carrying capacity
238907603	density-dependent population controls	Limiting factors have a greater effect as density increases Mostly Biotic Factors Competition for resources Predation Parasitism Infectious disease
238907604	density-independent population controls	Limiting factor effects are not dependent on the size of the herd Mostly Abiotic Factors Weather/Climate Related Natural Disasters
238907605	stable growth	population size fluctuates above and below carrying capacity Ex: undisturbed tropical rain forest
238907606	irruptive growth	growth may explode, then crash Ex: seasonal insects
238907607	cyclic growth	boom and bust cycles Ex: lynx and snowshoe hare; wolf-moose interactions Top-down population regulation Bottom-up population regulation
238907608	irregular growth	no recurring pattern; often caused by catastrophic events like natural disasters or major habitat destruction that cannot be predicted
238907609	asexual reproduction	Offspring are exact genetic copies (clones) of a single parent Examples: single-celled bacteria, corals, yeast, vegetative in plants
238907610	sexual reproduction	two organisms mix genetic material so offspring is a combination of both
238907611	r-selected species	reproduce quickly, high biotic potential, many offspring, little care to offspring; ex: insects (roaches), small mammals (mice, rats, rabbits), etc.
238907612	K-selected species	reproduce slowly, low biotic potential, few offspring, a lot of care to offspring; ex: large mammals like elephants, panda, kangaroo
238907613	late loss population survivorship curve	organisms in population live long life and often have few offspring but give offspring a lot of care; ex: large mammals
238907614	constant loss population survivorship curve	organisms die off evenly at all ages throughout lifespan; ex: song birds
238907615	early loss population survivorship curve	organisms in population die off at early ages, parents have many offspring but give little care to offspring; ex: fish, insects, etc.