Ecology Exam 2

population

group of individual of same species that live within a particular area and interact with one another

dispersion

spatial arrangement of individuals in a population

uniform

category of dispersion, due to territorality, allelopathy; antropogenic

clumped

obvious/descrete grouips, habitat patchiness

birth rate

average number of female individuals born in a set amount of time

mortality rate

proportion of population dieing in time

immigration

movement into a population

emmigration

movement out of a population

mark-recapture

closed models: Lincoln-Peterson and Schnabel

Open models: Cormack-Jelly-saber

schnabel estimate

mark every time, numbers stabilize

Dispersal

movement between populations

age pyramid

zero, negative, rapid

stable age distribution

age class proportion remains same over time

Life table

age specific summary of mortality rates of a population

2 types: Static and cohort

cohort

group of individuals born at the same time

monocapric

plants tat die after flowering

survivorship

plot log(survivors)

type 1 survivorship

low mortality early, higher mortality later

type II survivorship

constant mortality

type III survivorship

high mortality early

fecundity table

average number of offspring produced by a female at age x

R naught

net reproduction rate, average number of female offspring per female in a lifetime R naught=Sigma(LxFx)

r

instantaneous rate r=ln(lambda)

lambda

geometric population growth rate

lambda=e^r

represents year to year population growth rate

geometric growth

species change in size by constant proportion from one discrete time period to the next, insects and annual plants

exponential growth

continuous reproduction changes in size by constant proportion at each instant in time

continuous time

overlapping generations

doubling time

number of years it takes a population to double in size

cohort generation time

Tc

average time between female birth and its offspring

intraspecific competition

competition within same species decrease in fitness-reduced reproductive rate

competition

interactions between individuals for a required resource that has limited supply which leads to reduced fitness in both species

exploitation

species don't interact but use same resources

interference

direct confrontation with food or territory

scramble

leads to extenction

contest

better competitors sustain, less severe

density dependent

birth/death/dispersion changes with density of population

carrying capacity

max amount of individuals the environment can handle. at carrying capacity the growth rate is 0

net recruitment rate

number of individuals by which population grows over time

logistic growth

increase in population, immediate negative impact. S shaped curve of pop growth. Density dependent

timelags

oscillate around k

interspecific competition

competition between different species become specialized to reduce competition

density independent

effects the population the same regardless of density

el nino

affects weather patterns. Eastern Pacific waters are warm, dry winter in Jamaica

la nina

eastern pacific waters cool. moist winter in Jamaica

species interactions

species occupying same physical area can compete predators=prey, host parasite,mutualism

lotka-volterra

mathematical description of 2 species interactions

zero growth isocline

population status compared to carrying capacity, represent combined values of both species

Gause's Law

extinction results if one pop increases a bit faster than another

assuming same resources and constant cohort

fundamental niche

where species can live without predation/limited resources. has full amount of resources

realized niche

where species does live because predators/resources forced species to leave fundamental niche

character displacement

a shift in feeding niche affects morphology/behavior

allopatric

overlapping distributions of break size

sympatric

coexists-break size distributions dont have overlap

resource partitioning

different food, different times to eat, different areas, species use resources in the same way

true predator

carnivore, larger than prey or in packs

herbivore

eat mostly vegitation

parasite

predators but dont kill prey, live inside or on other organisms

parasitoid

insects lay eggs in/on another insect-eggs hatch and kill host

functional response

density of prey, increase in prey density increase in prey eaten

type I functional response

constant predation, independent of prey density

type II functional response

increase in number of preay and increase in handling time

type III functional response

low prey consumption at first but increases over time

numerical response

as prey population increases predator growth rate should respond, can regulate population growth

polyphagous

eat a large variety (omnivores)

oligiophagous

eat a few things, white tailed deer

monophagous

eat one thing, rare, no competition for food

optimal forage

predicts fitness, maximum energy intake

aposematic coloration

species taht have toxins and brightly colored

mullerian mimicry

similar color pattern shared by unpalatables

batesian mimicry

palatable looks like unpalatable

crypsis

camouflage to hide from predators

lotka-volterra predation model

dN/dt=rN-aNP

dP/dt=baNP-mP

MSY

maximum sustainable yield

compensation

removal of plant tissues stimulates plant to make more tissues

social parasitism

A type of parasitism where the parasite is partially dependent on the social system of its host.

top down

limit abundance of population by consumers

bottom up

limit abundance of population by nutrient/food supply

keystone species

strong interactor that has effect on energy flow and community structure

life history

record of major events relating to organisms growth/development/reproduction/survival

precocious puberty

the term used to describe the very early onset and rapid progression of puberty

r-selected

a measure of how rapidly the population can grow. refers to the selection for higher population growth rates.

k-selected

pressure for slower rates of increase

1.A estimate population size

lincoln peterson: N=Mn/m M=# of first marked m=# of marked 2nd n=# capture 2nd total sample=M+m

Schnable N=Sigma(CtMt)/Sigma(Rt) Ct=total fish in sample Rt=total marked Mt=total marked at alrge

Delury depletion CPUE=-0.199(cumulative catch)+512.7

1B atributes of a population

density and dispersion

1C different types of disperion patterins in populations

uniform, random, clumped

1D use of cohort and static life tables

cohort life tables used for plants and sessile organisms because they can be followed easily.

static life tables used on organisms that are highlly mobile/ long life spans.

Multiple cohorts, must be able to estimate ages

1E importantce of Rnaught, calculate r, lambda, Rnaught from life table

x=age lx=survivorship Fx=frequency Nx=number alive

Rnaught=sum(lxfx)

T=sum(xlxfx)

r=ln(rnaught)/T

lambda=Rnaught^1/T

2A geometric population growth

have discrete time periods. Population changes in size by a constant proportion from one time period to the next

N(t+1)=lambdaN(t) N(t)=lambda^(t)N(naught)

N(t)=population size after t generations

t=discrete time periods

lambda=any number 0

2B Exponential population growth

continuous reproduction changes in size by constant proportion

dN/Dt=rN and N(t)=N(0)e^rt (P=pe^rt)

N(t)=population size at each instant in time (t)

dN/dt= rate of change in population size

r=population growth rate

compare geometric and exponential: lambda=e^r, r=ln(lambda)

2C Describe shape of graph based on magnitude (r)

lambda<1 r<0 exponential decrease

Lambda=1 r=0 no increase or decrease

lambda>1 r>0 exponential increase

2E Logistic Population growth

s-shape population growth

dN/dt=rN(1-N/K)

dN/dt=rate of change in population size

r=population growth rate

N=population density

K=carrying capacity

(1-N/K)

Similar to exponential growth but slightly slower

at increased density--large difference in exponential and logistic

2G Types of competition

intraspecific-same species

interspecific-different species

scramble-limited resources equally rationed, leads to decreased survival rates

contest-winner/loser, leads to extinction

3A How does competition affect growth and development?

growth of individual less because less resources and nutrients

as density increases and resources remain the same, growth decreases--Density dependent

3B competition affects mortality

reduced survival at increased popoulation density. Higher mortality leads to less competition which leads to more growth. Self thinging to to lack of resources

3C Density Impacts Stress

Limited space, crowding=increased stress

hormonal changes (delayed puberty)=suppressed immune system=immature mortality

dispersal- adult aggression, males drive out other males, move from population, has advantage- less inbreading/ population expands/max survival and reproduction

3D Social rank/territorality impact

social rank: fighting, bluffing, threatening. Direct fighting-wolves. Bluffing-ramming. threat-bird fluffing.

territory: defend home range and habitat resources. Use songs, markings, or attacking.

Density dependent- as density increases, attacking increases

4A types interspecific competition

natural selection

competition leads to specialization and divergence

1.overgrowth= plants grow over competition

2.generate= chemical for negative impact

3.territorial= keep out other species

4.Encounter= physical encounter, negative impact

5.consumption= use up resources

6.preemption= take nesting site

4B Lotka volterra Model

Mathematically describes interaction of 2 species

Species 1 dN1/dt=r1N1(K1-N1-alphaN2/K1)

Species 2 dN2/dt=r2N2(K2-N2-betaNa/K2)

AlphaN2=effect species 1 on 2

BetaN1=effect species 2 on 1

zero growth inclines

dN/dt=0, zero growth

dN/dt<0,

represents combined values of Species 1 and 2

4C 4 outcomes of Lotka-Volterra

1. species 1 inhibits species 2

2. species 2 inhibits species 1

3. depends on starting opint

4. coexistance

4D Describe and examples of Gause's law

2 species competing for same resources cannot coexist if conditions remain constant

if 1 populations increases a bit faster than other population, they go extinct