reading check 175-188 k r species, population growth, etc.

niche generalists 3

live under a wide range of abiotic and biotic factors

equal distribution of individuals in various values and temps

adaptable and resilient to global warming

niche specialists

narrower curve, narrow temperature range on x-axis

thrive if environmental conditions are kept constant, food is abundant

vulnerable to changes

population/intrinsic growth rate

number of offspring an individual can produce in a given time period, minus the deaths of the individual/offspring during the same period

biotic potential

Under ideal conditions with unlimited resources available, every population has a maximum potential for growth

k-selected species

low intrinsic growth rate that causes the population to increase slowly until it reaches the carrying capacity of the environment

carrying capacity

limit to the number of individuals that can be supported by an existing habitat or ecosystem, denoted as K

r-selected species

species that has a high intrinsic growth rate, and their population typically increases rapidly

overshoot

When a population becomes larger than the environment’s carrying capacity

dieback

A rapid decline in a population due to death

survivorship curve

A graph that represents the distinct patterns of species survival as a function of age

type I survivorship

high survival throughout most of the life span,die in large numbers as they approach old age, k-selected species

type II survivorship

relatively constant decline in survivorship throughout most of the life span, squirrels/chipmunks

type III survivorship

low survivorship (a high death rate) early in life with few individuals reaching adulthood, r-selected species

density dependent factors

influences an individual’s probability of survival and reproduction in a manner that depends on the size of the population

density independent factors

has the same effect on an individual’s probability of survival and the amount of reproduction at any population size

population growth model

Mathematical equations that can be used to predict population size at any moment in time

fecundity

ability to produce an abundance of offspring

exponential growth model

estimates a population’s future size after some time; based on the biotic potential and the # of reproducing individuals current;y

4 assumptions of exponential growth model

• ideal conditions

• not limited resources

• population increases at biotic potential

• more births per unit of time

j-shaped curve

curve of the exponential growth model when graphed

• rate of change fixed

• magnitude of change rapidly increases for ts

how is exponential growth density independent

value grows by the same percentage regardless, and result is dependent on population

logistic growth model

growth is initially exponential, but slows as the population approaches the carrying capacity

s-shaped curve

• shape of the logistic growth model when graphed

logistic growth model predicts growth of what kinds of factors

density dependent factors like more competition for food/water/space bc independent r unpredictable

what else does LGM assume

survival of offspring depends on current population size and carrying capacity of environment

limitations of LGM 3

• seasonal differences

• food abundant at mating, not birth

• overshoot → resource depletion, dieback

explain gause experiment on density-dependent growth

• Both grew rapidly, slowed as food became limited, leveled off, showing carrying capacity

• Second experiment: doubled food supply → species grew faster, reaching twice the ogpopulation size

limiting resource

population cannot live without and in quantities lower than the population would require to increase in size

limiting resources of plants v animals

plants often limited by water and nutrients

animals by food, water, and nest sites

density independent factors explain

impact all individuals equally regardless of population size; natural disasters, death increases no matter what

explain oscillation

diebacks can drop populations below carrying capacity, but populations may grow again leading to repetition; stabilizes

what other limiting factors exist and what r the long term consequences

habitat → population can decline even if food exists

recovery of habitat can take a while

resource availability changes