Ecology Exam 2 Part 2

when both species are benefited

mutualism

when only one species is benefitted and the other is not affected

commensalism

when one species is benefitted and the other is harmed

exploitation

when both species are hurt

competition

when one species is not affected and the other is hurt

amensalism

types of exploitation

allelopathy, herbivory, predation, parasitism

competition with members of own species is what type of competiton

intraspecific

competition between individuals of two species (reduces fitness of both) is what type of compeition

interspecific

direct aggressive interaction between individuals observed short term

interference

type of competition where no need for individuals to interact directly and outcome determined by how efficiently each competitor use the resource

resource

interactions in which most of all of the life cycle of one organism occurs inside or on another

symbiosis

when there is a limited supply of suitable space for a species

resource limitation

ecological principle describing how plant mortality occurs in crowded, even-aged monocultures due to intense competition for limited resources like light, water, and space

self-thinning (3/2) rule

first to study competition in 1917

Arthur Tansley

observed closely related species occurring together often grow in different habitat and asked if interspecific competition led to separation of two species on plants on different soil types

arthur tansley

arthur Tansley looked at bedstraw species in what habitats

bedstraw grown on acid soil and alkaline limestone hills

what did Tansley find about Galium grown on the two soil types

they grew on both soil types so plants not limited to a certain soil type

results of only G. saxatile on acid vs. basic soil

results of only G. sylvestre on acid vs. basic soil

results of both species planted together on acid vs. basic soil

did better on acidic soil / did better on basic soil / the basic adapted G. sylvestre grew better than the G. saxatile on basic soil and vice versa but both grew

Tansley discovered that species were adapted to (__), which is the ecological space where species are specialized upon. There was a clear (__) of native species in soil they are adapted for

realized niche / competitive dominance

first attempted to model interspecific competition was (__), based models on (__) equation which is a model of (__) competition

lotka and volterra / logistic / intraspecific

in the logistic equation, the term N/K measures

effect on growth of population by adding new member of same species (intraspecific competition)

what is the modified logistic growth formula for interspecific competition by lotka and volterra

dN/dt = r₁N₁ ([K₁-N₁-α₁₂N₂]/K₁)

proposes that two species with identical niches cannot coexist indefinitely, which leads to the prediction that coexisting species will have different niches

competitive exclusion principle

since the effect of one species on the growth of another would not likely be identical to a species effect on its own growth, (__) must be made to analyze both inter and intra specific competition

competition coefficient

alpha, competitive effects of competing species

competition coefficent

what does α₂₁ mean

effect of species 1 on species 2

what does α₁₂ > 1 mean

competitive effect of species 2 on species 1 is greater than effect of individual of species 1

based on lotka and volterra equation, when do we know populations of both species stop growing

when dN/dt equals 0

equations for straight lines where everywhere along the lines population growth is stopped

isoclines of zero population growth

above an isocline of zero growth, the population of a species is (__). below it, the population is (__)

decreasing / increasing

what happens when N1= K1

environment is completely filled by species 1 and no species 2

the Lotka-Volterra model predicts that one species will exclude the other when the isoclines

do not cross

if the isocline for species 1 lies above that of species 2, species 1 will

eventually exclude species 2

coexistence between species is only possible when the isoclines

cross

the lotka-volterra model predicts that species coexist when…

intraspecific competition is stronger than interspecific competition

at K1, species (__) wins, population size equals (__). (__) strength is stronger for species (__)

1 / K1 / interspecific / 1

at K2, species (__) wins and population size equals (__). (__) strength for species (__) is stronger

2 / K2 / interspecific / 2

there is (__) strength when they cross. eventually, (__) wins. coexistence eventually drives one species (__)

equivalent / species 1 or 2 / extinct

how many outcomes of competition by lotka and volterra are there

4

Gause used (__) to model Lotka-Volterra competition

P. aurelia and P. caudatum paramecium

studied would one of these two species drive the other to extinction if grown together in microcosms where they were forced to compete with each other for a limited food supply

Gause

difference between P. aurelia and P.caudatum

P. aurelia is smaller, has 2 micronuclei and posterior end is more round whereas P.caudatum has cylinder cigar shape and one micronucleus

Gause demonstrated resource (__) by growing pure populations in presence of two different food concentrations. He observed (___) growth with obvious (__) at both full and half strength concentrations of food. when food availability was halved, the carry capacity was (__). thus when grown alone, carrying capacity was determined by

limitation / sigmoidal / carrying capacities / reduced / intraspecific competition

when grown together, what did Gause find

P. aurelia survived but P. caudatum declined

what did Thomas Park study to show outcome of competition depends on environment, they infest stored grain products

flour beetles

Thomas Park found that in hot-wet environments, species of flour beetles grow separately had what growth? what about when grown together?

both species had healthy and persistent populations / only one species sustained

under such intermediate conditions, the species establishing itself in greater numbers first generally wins out in competition, a phenomenon known as

priority effect

with flour beetle experiment, outcome (___) assured because (__) conditions and winner was (__)

not / intermediate / unpredictable

if the competitive exclusion principle is in place, how do species coexist?

natural selection reduces competitive pressure by specialization into realized niche

what did Robert MacArthur show with warbler species about competition

resource partitioning. warblers coexist on same resource by subdividing niche

competition can have short term ecological effects on niches of species by restricting them to (_) yet these species may retain their capacity to inhabit the fuller range of environments called (__)

realized niche / fundamental niche

t or f: if competitive interactions are strong and pervasive enough, they may produce an evolutionary response in competitor population, an evolutionary response that changes fundamental niche

t

Connell discovered that (__)plays a key role in determining the lower limit of Chthamalus barnacles within the intertidal zone

interspecific competition

interspecific competition can lead to (__), the circumstance in which two species differ more from each other in geographic areas where they occur together than wehre their distributions do not overlap

character displacement

resource partitioning and niche specialization caused by competition leads to

niche differentiation

ecological space where competition is most severe where two species occupy mutually exclusive microhabitats in nature

niche overlap

niche overlap due to combination of

competition and difference in fundamental niche

two species living in separate geographical ranges

allopatric

two species occuring together

sympatric

when species are allopatric, their beak sizes are (__), but beak sizes are (__) when species are sympatric

similar / different

what was found on Santa Maria, San Cristobal where G. fuliginosa and G. fortis coexisted?

what was found on Los Hermanos where G. fuliginosa was allopatric?

what was found on Daphne where G. fortis was allopatric?

no overlap between beak sizes / its beak size could get larger because no competition from other species / its beak size could be smaller because no competition from other species

what do emerald jewel wasps do to cockroach and what type of relationship is this

inject pasasitoid venom that paralyzes cockroach and lays egg on roach. larvae burrow into cockroach and feed off of it / exploitation

populations of a wide variety of predators and prey are not (__) but rather (__) in abundance over periods of days to decades. increases/decreases between predator and prey (__) each other and fluctuations are (__). (__) always cycles higher

static / fluctuating dynamically / mirror / regular / prey

Lotka Volterra assumes host population grows (__) and population size is limited by (__)

exponentially / predators

explain the meaning of lotka-volterra host population growth equation

dN_h/dt = r_hN_h - pN_hN_p

rate of host population change equals exponential rate of increase by host population (per capita rate of increase times number of hosts) minus number of prey or hosts killed by predator (number of hosts times predation rate times number of predators)

explain the meaning of lotka-volterra predator population growth equation

dN_p/dt = cpN_hN_p - d_pN_p

rate of predator population change equals rate at which hosts are converted to predator offspring (host to predator conversion rate) minus number of predator deaths

a rise in prey population is followed by (__) in predation. an increased number of predators causes a (__) in prey population. as prey population falls, it will support (__) predators. with fewer predators, the prey population (__) again. this create a cycle of (__)

rise / decrease / less / rises / oscillations

during Gause’s experiments with paramecium and protist didinium, in the absence of refuges and immigration, what happened to the populations.

predator quickly consumed all paramecium and both went extinct

during Gause’s experiments with paramecium and didinium, adding a refuge like (__) affected prey how? predator how?

sediment / gave paramecium somewhere to hide so population persisted / predator became extinct

during Gause’s experiments with paramecium and didinium, cycles maintained only when simulated (__) of (__)

immigration / predator

situations in which members of an exploited population have some protection from predators and parasites

refuges

was Huffaker able to see the oscillations in his experiment on mites and oranges

only after making it complex and using 120 oranges

how does complexity of environment affect stability and interactions and species

complexity increases stability and helps maintain interactions and number of species

how does availability of refuges affect p in Lotka equation

p (rate of predation) is lower when more refuges

t or f: numerical response eventually levels offa t the point where further increases in prey density no longer produce increased predator density

t

occasional protection in large numbers over short time that prevents predators from building up

predator satiation

list the variety of refuges utilized by prey

spatial, flight, size, large groups, habitat, behavioral

list an example of crypsis

moth resembles dead leaf on forest floor in Costa Rica

(__) store two chemicals (hydroquinone and hydrogen peroxide). when threatened, the two chemicals are (__) and undergo violent reaction. boiling foul smelling liquid becomes a (__) and expelled with popping sound. this is an example of (__) defense

bombardier beetles / mixed / gas / chemical

list ways prey avoid predators

refuges, crypsis, chemical defense, mechanical defense, mimicry, behavior

poison arrow frogs utilize (__), which is an example of (__) defense. they have a brilliant advertisment of toxicity. golden dart frog native to columbia currently considered most poisonous vertebrate also utilizes this.

aposematic coloring / chemical

example of mechanical defense

porcupine needles, turtle shell

what makes up the mimicry complex and explain parts

model (dangerous organism that is copied), mimic (nondangerous organism copying model), and dupe (predator being fooled)

list an example of batesian mimicry

caterpillar backside looks like venomous snake head or non-venomous snake looks like venomous snake

how do two snake populations have to live for batesian mimicry to occur

sympatric

playing dead is a behavior used to avoid being eaten by predators because many predators like fresh meat. this is called

catalepsis

the eastern hognose snake uses (__) to avoid predators. they (__) necks and (__) loudly. if that doesn’t work, they (__) by rolling over with tongue out and remain limp. if that doesn’t work, they may (__)

intimidation / inflate / hiss / play dead / bite

synchronous widespread seed and fruit production is known as

masting

how do oak trees use predator satiation (swamping)

produce many acorn fruit only occasionally so cicadas cannot specialized on resource

relationship that increases fitness of one species while reducing fitness of other

parasitism

(__) consume tissues or body fluids of organism on which it lives called the (__). they typically harm but do not (__) the organism they eat

parasites / host / kill

t or f: parasites are found in all kingdoms

t

bacteria, fungi, and protists, usually microscopic organisms that cause diease

pathogen

number of host species that a single species of parasite can infect

host range

do parasites have a large of small amount of possible host species? this is called?

small / host specificity

host range limits due to (__) processes that evolve in (__) with hosts. as frequency of parasite trait increases, it will select for gene (__) to parasite in host. (__) is always a step ahead and (__) is trying to keep up

coevolutionary / parallel / resistant / parasite / host

species must constantly adapt and evolve against co-evolving opposing species just to survive and maintain their relative fitness is called the

red queen hypothesis

when you remove the ability to keep changing and evolving, such as if a population gets small and loses diversity, the population will be pushed to

extinction

for an evolutionary system, continuing (__) is needed to maintain fitness. why are cavendish bananas at risk of extinction?

development / the banana is triploid and cannot sexually reproduce so more susceptible to Panama Disease since no diversity

list an example of parasites altering host behavior

worm goes into arthropod. usually arthropod resides at bottom on pond, but the worm causes it to go up towards the light, leading to a higher chance of being eaten by a duck and allows it to produce more worms