Population Ecology

APES

what are the 3 population distribution/dispersal

uniform, cluster, random

describe characteristics of a clumped population distribution

-most common distribution

-usually K-selected

-helps species have an increased chance of survival

-happens bc resources are usually found in patches

describe characteristics of a uniform population distribution

-rare in nature to be evenly spaced

-happens when resources are scarce

-usually plants; lacking water and nutrients

describe random pop. distribution

-individuals in pop. are spaced out unpredictably

-happens w too many resources

-pretty rare in nature

-usually plants or insects and fungi

why do species live together in clumps

-they tend to cluster where resources are more avaliable

-groups have higher chance of finding clumped resources

-packs make it easier to get prey

-protect one another from predators

-Ex. elephants, humans, lions, schools of fish

what 4 factors determine population growth

birth

immigration

emmigration

death

whats the population change formula

pop.change= (births+immigration) - (death+emmigration)

what controls the size of a population (hint: that graph)

environmental resistance

what are some examples of environmental resistance

light

water

food

space

nutrients

what is biotic potential

the max reproductive rate of a population under ideal conditions

what IS environmental resistance

all factors that act to limit the growth of a population

what is carrying capacity

max population a given habitat can sustain

Describe overshooting

when a species exceeds the carrying capacity. this causes an effect of a huge drop in population numbers from losing resources

-usually R-selected species

describe a J-curve

-exponential growth

starts slow then accelerates to carrying capacity when meets environmental resistance

-usually R-selected species

Describe an S-curve

-logistic growth

decreased pop. growth rate as the population reaches carrying capacity

-usually K-selected species