Biol 313 Final material Flashcards
(123 cards)
1
Q
Define predation
A
one organism feeds on another, thereby killing & consuming some portion (or all) of it
2
Q
Define prey/victim
A
is organism that is killed
3
Q
Define herbivory
A
Loss of tissue in plants, due to grazing by herbivores, the plant does not need to be fully killed in herbivory
4
Q
Why are prey numbers negatively impacted by predation?
A
predator impacts the prey negatively by killing prey, more predator results in low prey abundance
5
Q
How does the interaction of prey killing predator impact prey in terms of selection?
A
This causes selectional pressure on prey and causes prey to do evolutionary adaptations in order to avoid predation
6
Q
How does the interaction of prey killing predator effect predator in terms of selection?
A
The predator needs prey to get energy, more prey is more energy, in response to prey having adaptations to reduce probability of predation the predators also adapt to overcome these defenses
7
Q
What do we expect from lynx and hare cycles in the hudson’s bay data collection?
A
We expect that when hare popln is high lynx popln is also high as there’s more prey for lynx to sustain themselves on
8
Q
What are the three characteristics of lynx and hare cycles?
A
They have regular cycles, the cycles match between species, and the cycles of populations decline and then start again around every 10 years
9
Q
What was charles elton’s theory as to why the classic lynx and hare cycle behaved this way?
A
sunspots- said that spots on the sun that produce less light and therefore less light intensity on the earth will effect plant growth which will then cause decline is hare reproduction, which will then cause decline in lynx popln
10
Q
Was charles elton’s sunspot theory correct?
A
No, because the sunspot cycle did not match up with the lynx and hare cycle
11
Q
What was keith’s overpopulation theory?
A
that when the hare population gets very compact diseas is easily spread, and physiological stress increases will results in hare popln crashing and lynx popln follows due to starvation
12
Q
Was keith’s overpopulation theory supported by data?
A
No, he suggested later on that we should have long term studies instead of more theories
13
Q
What was Krebs lynx and hare experiment
?
A
He started a study that involved all three trophic levels, this experiment had three controls, one for each group. For the second treatment he gave hares food and then plant nitrogen, for the third treatment he included predation by placing an electrical fence, he also put bare food and a fence and then also added nitrogen to plants
14
Q
How is the hare lynx cycle impacted from both the bottom and top of the food web?
A
Hares eat the best food first, this leads to depletion of it , then they go to their second choice of food, as hares increase in density they deplete food, soon the pop declines as the quality of food decreases (bottom up control)
Hares when they peak in popln, predators do as well cause they have more food, then hares decrease as predators increase, overtime as hares decrease predators also decrease as no food for them (top down control)
15
Q
What species are snowshoe hares prey to?
A
lynx, coyote, great horned owls, mink
16
Q
At hares peak density what percentage does predation account for their mortality?
A
60-90%
17
Q
why does the hare population decline?
A
because they have low food (due to high popln) and high predation
18
Q
Why is there a lag in the hare and lynx cycle, why do hares decline first?
A
This is because as hares decline lynx catch them easy have a delay in response, also because as hares decline it doesn’t instantaneously effect the lynx population and lynx can still have children from the previous nutrients they got before the hares declined
19
Q
How does the hare and lynx cycle start back up again?
A
plant population will grow as prey decreases, this well then cause prey to increase and then cause lynx to increase- takes about 10 years to compete this cycle
20
Q
If there’s more victims, what’s the effect on prey?
A
positive
21
Q
If we had prey with no predator what would the eqn be and why?
A
would be dV/dt= rV
where V= prey abundance
r= rate of growth of pop
this is because if we had prey with no predator we would expect the prey popln to grow exponentially
22
Q
If we include predators in our prey growth eqn, what would the eqn be and why?
A
dV/dT= rV-alphaVP
alpha= capture efficiency
V= prey abundance
P= predator abundance
r= rate of pop growth
include predator and victim in the output of prey as when they both increase, interactions between them increase, and more predation occurs
23
Q
Describe the growth eqn for predators on their own?
A
dP/dt= -qP
this is because the predator will have no food source so the pop will exponentially decline
24
Q
describe the a growth eqn for predators with prey factored in
A
dP/dt= BVP- qP
B= conversion coefficient (is energy that prey gives predator through consuming converted into how many predator offspring are born)
V= victim (prey) abundance
P= predator abundance
q= rate of decrease
For our out of predator need both prey and predator so that why we multiply them
25
What does p^ and V^ stand for?
p^ is the number of predators at the prey equilibrium. When dV/dt is 0.
Equals
p^= r/alpha
V^ is the prey number at the predator equilibrium. When dP/dt= 0
V^= q/B
26
if we’re below line for P^= r/alpha, what happens to prey? what if we’re above?
If we’re below line then we have less predator then at equilibrium so orey increases, above line more predators so prey decrease
isocline is predator count where prey remains constant
27
If we’re below isocline for V^= q/B what happens? What about if we’re above?
If we’re below line then we have less prey so predator decrease, if we’re above isocline more orey so predator increase
the value of isocline is the number of victims needed to keep the predator popln at equilibrium
28
does the lotka-volterra predator prey model have the same cycle as the hare and lynx cycle
yes
29
Explain how gause tested the predator-prey cycles experimentally?
Put predator (didinium nasutum) and prey (Paramecium caudatum) together and they eventually went extinct, the he added refuge for prey which allowed them to surivive but predator still just went extinct, the added immigration by adding new prey which allowed us to see the looks colters model cycles expected. Prices we need open systems for environments with orey and predators to work.
30
Describe Huffakers experiment and how it aided to the understanding of the lotka volterra model?
huffaker made habitat more conked by adding different patches, some were source patches with no predators, he observed the experiment overtime and w the complexity in the system he saw cycles as population renewed themselves with source patches and then sunk near predators.
31
L23 What is the red queen hypothesis?
represents an evolutionary arms race, predator has to adapt to catch prey, prey adapt to avoid predator and the cycle continues again and again.
Red queen hypothesis basically states that for species to stay coadapting they will do coevolution, evolution in response to each other.
Coevolution is big outcome of interaction between species.
32
What is the first step of prey capture? How can it be avoided?
The first steep is encounter, to avoid this prey can leave the area, enter a refuge, or do behavioural changes like being active at a different time of day
33
Whats the second step of prey capture? How do you avoid this?
Detection, to avoid this prey can decrease their conspicuousness Prey can play with predator by moving in strange ways to confuse predator as to whether it’s a prey, it also might hide in a big group forcing predator to be overwhelmed or not see it as a prey. Overwhelmed as in the predator might reach it’s feeding capacity- limit to how much prey the predator can eat over time, if the predator has a type two or three functional response
34
What is masting?
Trees produce seeds and cones over the same interval of time, have big production over one period of time so that even if a few seeds are consumed success of reproduction will still be high as there's so much of them
35
What is the third step in the process of prey capture? How do you avoid this?
Identification, predators need to recognize the prey as prey, to avoid identification they go through crypsis, aposemitism and mimicry
36
What is crypsis?
ability of prey to avoid identification by blending in the background (camouflage)
37
How do organism avoid predation by playing dead?
Allows them to be perceived by the predator as something they should not eat, lizards will play dead to avoid identification as food as snakes don’t eat dead things
38
What is aposematism?
Is the opposite of crypsis, advertises a warning, So organism will ingest toxins that renders them bad tasting
If they have weird colors or funky patterns will show off the fact that they are toxic for ex: lionfish w big spikes.
Is honest advertising
39
What is a form of mimicry that is similar to aposemitism but not actually it?
This is batesian, in which where a species mimics an actually unpalatable one, The mimic is actually godo to eat but relies on previous encounters that predators may have had w the model in order to make the predator avoid them.
40
Are viceroy and monarch butterflies an example of mimicry?
No as they are actually both toxic, is instead aposematism
41
What is mullerian mimicry? Provide an example?
Here we have different species that are not relate d gentically but look simiarly toxic and are both toxic, is an example of aposematism.
Example of this is both bees and wasps, both sting and have bright colors but they avoid predator encounters because the predator can encounter a wasp and know to avoid both bees and wasps.
42
What is the fourth step in the process of prey capture?
Approach, predator needs to get close enough to capture prey, to avoid this, prey can outrun the predator or hide
43
What is the life-dinner principle?
The prey is running for its life, a lot more at stake for prey vs predator so therefore this step causes more selective pressure on prey
44
What is the fifth step of prey capture?
subduing prey, to avoid this prey can fight it off, can produce mucus and slime to slippery and avoid being grabbed, or can detach a part of its body (automy)
45
What is an example of autotomy?
scorpions, after detachment the tail is still active which distracts predator and gives scorpion time to run, downside for scorpion is it can't sting anymore or defecate soem organism can regenerate missing limb which is better
46
What is an example of prey fighting off a predator?
the bombardier beetle, which releases benzoquinones are toxins, release this when caught by predator to fight it off. Can see this associated w consumption as well and prey can release toxins once in predator and them come out.
47
What is the 6th step in the process of prey capture, how can you avoid it?
Consumption, having toxins that prey relases after it dies could be helpful for it's feelow species as predator will now avoid em
48
Define herbivory?
Herbivory = consumption of plant or plant parts by animals
49
What are herbivores also referred to as?
Herbivores are primary consumers because they’re at primary consumers, plants are primary producers.
This a plus minus interaction because herbivore gets plants but plants get death or partial death.
50
What is a metaanalysis?
A meta analysis is a paper that takes many studies and compiles them
51
When herbivores are present what happens to plant fitness?
in general, lowers
52
Can herbivores promote plant growth?
Plants respond to herbivor by increasing productivity so yes, through overcompensation
53
Can herbivores promote plant growth?
Plants respond to herbivor by increasing productivity so yes, through overcompensation
54
How can herbivores control the distribution and abundance of plant species and alter plant community structure and composition?
Herbivores present can control distribution and abundance of plant species and in turn impact the plant community.
In what proportion do we see each plant in the community be represented? This is impacted by herbivores.
For ex if they’re specialists they will affect one plants rep a lot but generalists will lower all plants popln.
55
Give an example of generalist herbivore and a specialist herbivore
specialist- koala
Generalist- deer
56
Give an example of a herbivore that prefers to feed on dominant species, how does that alter plant communtiies?
Bison feed on tall grass, leaves a lot of sun tp hit fields and gives rise to new plants
57
Do you expect low or tall grass where cattlles graze?
Low grass and uniform grass as cattle is a generalist herbivore so the community structure is fairly homogenous.
58
What is a practical application of herbivores?
Using herbivores to control invasive plant species
59
Whats an example of using herbivores to control an invasive species?
prickly pears were released in australia and began taking over in 1925, this plant became invasive and pushed away native plants, so what happened was predator release. Cactus moth was the predator for it, so w out the herbivore they were able to grow in very very large numbers.
Australians then introduced the cactus moth in 1925.
60
What is another example of herbivores controlling invasive plant species?
Klamath weed, this plant poisoned local species, used two leaf bettlbeetle to reduce abundacne of st johns worth weed
61
What is an example of an unsuccessful biological control
Cane toads were introduced in Australia to protect sugar cane from beetles, wanted toad to prey on beetles.
Worked at first, but cane toads did not stop eating beetles, they also produce toxins so they have no natural predators in Australia the way they did in Hawaii. Ate eveyrhting and put native wildlife like reptiles at risk.
62
Why is there still an abundance of plants despite alot of herbivores?
Predators and population numbers and kept in check by disease parasites, plants can also defend against herbivory.
63
What is the assumption of the green world hypothesis?
That most terrestrial organisms have three major trophic levels (plants, herbivores, and carnivores)
64
What is the green world hypothesis?
Herbivores don’t consume all of the food resources (plants) because predators keep their numbers in check.
65
How is top down control and the GW hypothesis connected?
call it top down control because it comes from top of food web and influences everything below it.
66
How is top down control and the GW hypothesis connected?
call it top down control because it comes from top of food web and influences everything below it.
67
What is an example of the GW hypothesis in action?
dams in islands caused flooding which created a series of islands, predator free islands had a decimated understory
68
What are the three ways plants fight back?
Have mechacnical (structures on plants), biotic (animal guards), and biochemical (synthesis of toxins) defenses
69
Explain how plants defend themselves mechanically?
for ex trichomes, plants have structure which can njure predators, trichome are little hairs on plant which can catch predators.
another example is passifloraceae which are fed upon by larve butterflies the plants with trichomes do not get damged by this larvae but species w out do.
70
What is an example of a biotic and mechanical defense?
acacia trees and ants, ants defend tree by fighting off predators and making the tree unpalatable.
71
L26 Define symbiosis
long-term and close interaction between at least two species
72
What are the three types of interactions in the mutualist-parasite continuum
mutualism (both benefit), commensalism (one benefits and the other doesn't), and parasitism (one benefits and the others harmed)
Interaction fall along this spectrum
73
Define parasite
spends all or part of its life cycle in or on another organism, which suffers some reduction in fitness.
(doesn't have to die)
74
What is the correlated life history between parasites and host?
the parasite usually develops extreme specialization that allows for them to successfully get a host, also has frequent coevolution as host evolves to remove it and parasite evolves to stay on it
75
What are types of parasites?
Split up by size, micro and macro.
Micro- is small, has short generation time, typically reproduces within host, usually is a disease, virus, bacteria, protozonas, and protists
Macro- Larger/longer generation time
Usually doesn't complete its life cycle within the host (ex flatworms, roundworms, fleas, ticks)
Location:
endo- is inside host
ecto- is outside host
76
What are the properties of parasites that allow them to feed off a host?
mechanism of attaching (persisting within) to hosts for long periods of time
Modified limbs, hooks, barbs…
ex: hookworms
withstand host’s defensive responses
Animals – Immune Responses
Plants – Chemical Responses
contend with natural enemies
Parasites of parasites!
77
What is an issue parasites face?
Can't reproduce and issemninate because they're stuck staying on their host
78
What problems cause parasites to need to specialize?
Problem for all parasites is the same:
meet all nutritional demands on host or die
cannot leave initial host and choose new individual
compare to free-living organisms that can “nibble and leave”
Conditions of previous properties are usually specific to hosts
Therefore, specialization is a necessary outcome
79
What is the cymotha exigua?
is called the tongue eating crustacean, is parasite, crawls inot fish mouth through gills, consumes fish tounges, and replaces the tongue and stay for as long as the fish is alive
80
What are hookworms?
larvae enter through the skin of feet, migrate to lungs and trachea, and then reside in the small intestine feeding on blood
81
What are naegleria fowleri?
Are called brain eating amoeba, they neter through the nasal passage at the flagellate stage and then migrate to brain via olfactory nerves and consumes nervous tissue, eventualky enters floor of cranium and causes fatal hemoraghing, called an accidental parasite bcuz they aren't specialized to eat brain and normally eat bacteria
82
What is brood parasitism?
a female finds the nest of a ‘host’ and lays her egg when the host is absent; host then raises the offspring.
83
How parasites avoid host realizing her egg got kicked out for a parasites?
They adapt to make them lookm the same
84
How is brood parasitism helping parasite?
parental care requires energy, parasite saves energyy and host loses it
85
How successful is the parasitic lifestyle?
Very, has high species richness and evolves constantly
86
Define parasitoids
similar to parasites where they are in or on host but have larvae develop on host which causes death to the host
87
what species are parasitoids?
hymenopterans (bees and wasps) but also flies and some beetles
88
Describe the ichneumon wasps
adult wasp put eggs inot butterfly, eggs turn into larvae, these larvae consume host, leave the nervous system and essential organs till last to keep the host alive as they turn inot adults.
89
What's a human use of parasitoids?
encarsia formosa (wasp) used to control pests of tomatoes (whiteflys)
90
L27 Describe host parasite coevolution?
Have a potential for arms race where one parasite build on other.
See coevlution where a change in one influences a change in noather, is arms race because some change sin host can have to do w avoiding parasite, but some change sin host can happen due to other selective pressures.
91
Define reciprocal speciation?
When parasite follows its host in evolving leading to speciation in response to host speciation
92
What is niche partitioning, describe via an experiment?
lice and pigeon were in a cage for four years, lice are easier to pick away from if there's a contrast in color, so lice adapted by having darker lice be aroudn neck and lighter ones around feather, helped them avoid competiton with other lice and blend so pidgeon wouldn't shove them off.
93
What is direct transmission?
Parasite needs to be at right place and right time to stay closely linked to that host, direct transmission is when parasite goes from one host to another.
94
What is direct transmission?
Parasite needs to be at right place and right time to stay closely linked to that host, direct transmission is when parasite goes from one host to another.
95
What is the definition of of a primary host?
the reproduction and offspring of parasite eggs happens here
96
What is the definition of an intermediate host?
is an organism required for a developmental stage of the parasite
Goal of using na intermediate host is to get back to the definitive host.
97
What is an accidental host?
hosts that are accidnetllay effected but parasites don't die here.
98
What are the two ways parasites are transferred?
Direct transmission or transferred via a vector
99
What is a vector?
Vector usually not harmed by the parasite
Vector generally have a life cycle that facilitates transfer to suitable host
ex: mosquitoes for the transmission of malaria and West Nile virus
100
Give examples of how parasites cause behavioural modifications in hosts?
Microphallus piriformes – Fluke (flatworm)
Causes IH (periwinkle snail) to move to the surface in the intertidal zone so it can be eaten by sea gulls (DH)
Euhaplorchis californiensis – Fluke (flatworm)
Causes IH (killifish) to perform a complex ‘dance’ at the surface of the water, making it up to 30x more likely to be eaten by birds (DHs)
Spinochordodes tellinii - Worm
Adults live & breed in water so grasshoppers & crickets ingest larvae when they drink the water
Larvae develop inside the host, release chemicals which alter the CNS, causing host to jump into the nearest body of water and drown
101
Give examples of how parasites cause behavioural modifications in hosts?
Microphallus piriformes – Fluke (flatworm)
Causes IH (periwinkle snail) to move to the surface in the intertidal zone so it can be eaten by sea gulls (DH)
Euhaplorchis californiensis – Fluke (flatworm)
Causes IH (killifish) to perform a complex ‘dance’ at the surface of the water, making it up to 30x more likely to be eaten by birds (DHs)
Spinochordodes tellinii - Worm
Adults live & breed in water so grasshoppers & crickets ingest larvae when they drink the water
Larvae develop inside the host, release chemicals which alter the CNS, causing host to jump into the nearest body of water and drown
102
explain how flatworms cause behavioural chnages in IH snail to get to DH bird
parasite eggs within bird feces are ingested by snail (IH)
hatch and penetrate host tissue, develop into sporocyst with conspicuous colours
sporocysts protrude into snail tentacles and move rhythmically to attract birds (DH)
103
What is the cordyceps fungi in zombie ants?antsts?
endo parasitoids
104
What commensalim, list two examples?
commensalism is a plus neutral effect, examples are remora which feed on big whales leftovers and egret which feed on bugs on cattle.
105
L28 Define mutualism
= mutually beneficial interactions
between members of different species
106
What is reciprocal exploitation?
both species are exploiting eachother in a controlled parasitism, but the benefits of exploiting eachother outway the costs, this is mutualism
107
Explain how mutualism plays a fundamental role in ecosystems?
For ex mutualism with n fixing bacteria and legumes, bacteria take nitrogen and convert it usually form for legumes
108
Explain how mutualism plays a fundamental role in ecosystems?
109
What is facultative mutualism?
Is not necessary for survival of species, here two species provide fitness benefits to eachother.
110
What is an example of facultative mutualism?
Example of this is ants and aphids, ants get food and aphids get protection but both can still live w out eachother
111
What is obligate mutualism?
Two species provide fitness benefits to each other and require each other to persist
ex: of this is lichen which is fungus + alga
112
Describe the mutualism-exploiter continuum?
The benefits of mutualism weight out the harm, however it’s not a friendly interaction, and can switch from parasitic to mutualistic depending on the environment, is dynamic ie a continuum
113
Can mutualistic relationships become commensual?
Yea for example when one of the species adapts to counter the negative impacts of the other taking from them and then has no effect, the relationship can become commensal
114
What is a resource resource relationship?
Is a type of mutualism where nutrition is traded for another, examples are mycorrhizae and fungi (plants get p and n and fungi get sugars) or N fixing bacteria and legumes (legumes get N and bacteria get sugars)
115
How is the relationship between orchids and fungi an obligate mutualism?
This is because the orchid seeds cannot gerninate and grow w out fungi as fungi gives it all of its food, this has caused mutualistic convolution of orchids and fungi in order to be able to surivive better with eachother
116
What are service-resource relationships?
Are a type of mutualism, for ex pollinators trade get nectar and pollen from plants and plants get their pollen dispersed
117
How does pollination evolve in terms of coevolution and reciprocal selection?
Plants will evolve to have better pollen to attract pollinators more, pollinators will then pollinate the plants more which gives better plant dispersal and survival. Pollinators will in turn evolve to have better structure for pollinating for ex longer nectar spurs
118
What is runway evolution?
Adaptation is matched by another adaptation, for ex plants will evolve to get a longer nectar spur in order to match the moths long proboscis (nectar getter) and then moth will in turn evolve to get a longer probacis in order to be able to avoid being eaten and get nutrients easier so you get selection for long proboscis
119
What is zoochory?
Is dispersal of seeds by animals, is a service resource type of mutualism, plants give high sugar food to animals as resource and in return the service is dispersal of seeds
120
What are service service relationships?
Type of mutualism, rare to find strict cases of this for ex clownfish and anemones, clownfish and anemone both get protection but hard to classify as fish eats morsels of other fish that are caught by the anemone so also resource?
121
What happens when mutualism is exploited?
Exploiters gain benefits of mutualism without incurring any of the costs, one of the partners in the relationship cheats of low levels it’s sustainable but if too much mutualism becomes parasitic
122
Give some examples of occasional cheating in mutualism?
cleaner wrasses occasionally feed on host tissue and host fish will occasionally eat cleaner wrasse
tobacco plant don’t produce nectar but still get pollinated
123
What is persistent cheating in mutualism?
has a third species that ruins mutualism between two partners, for ex orchids that mimic nectar producing ones to attract insects but never produce nectar, or nectar robbers that feed on plant to get nectar instead of pollinating flower
