Exam 2
According to the Scitable article based on Krebs' exclosure studies, the changes in hare density in the lynx hare system are actually due to Question 11 options: A) The interaction between several predators and the nutritional quality of hare food plants B) the severity of the winter on hare offspring. C) mostly the lynx D) almost entirely the availability of food for hares.
A
According to the article, beavers are considered Question 2 options: A) a keystone modifier species because they alter the environment determining the presence of other species. B) Keystone competitors because they rapidly saturate a watershed C) keystone predator because they eliminate the aspen trees in many locations. D) Keystone prey item because the wolves and foxes depend upon them
A
Finches on the Galapagos show what pattern according to the article? Question 6 options: A) species occupying the same island have very different size beaks B) Finches migrate to new islands if there are too many species on their island. C) when species coexist on islands, they drive each other to extinction. D) Species living alone on islands more specialized bills compared to islands they share with other species.
A
In the trophic model of keystone predation, otters have what kind of effect on kelp? Question 9 options: A) An indirect positive effect B) A direct positive effect C) An associative positive effect D) An indirect negative effect
A
Islands are useful as study units because Question 2 options: A) all of these answers are examples of why islands are useful for scientists. B) they have fewer species than continents C) they can allow replication of experiments D) Island patterns may provide insight for habitat fragmentation on continents.
A
The rate of colonization decreases with species richness on the island because Question 6 options: A) More species means more occupied niches and less niche space for new colonizers so competitive exclusion keeps them out. B) When there are fewer species on the island it is less likely new species will colonize C) these islands are closer to the mainland where there is a greater chance of colonization D) The more species on an island the closer it is to the mainland
A
The reason keystone predators in the diversity model actually maintain diversity is because without them there would be Question 8 options: A) competitive exclusion B) a less peaceful ecosystem C) more prey D) more competition
A
What predators are reintroduced to a habitat after having been extirpated, which of the following thought to be an additive top down effect? Question 14 options: A) Prey spend more time watching for predators and less time eating so populations grow more slowly. B) Prey run more often, causing signficantly more disturbed soil and reducing forage. C) Prey make more offspring because they sense they may not live long. D) Prey items eat faster in the presenc of predators causing the population to grow faster.
A
Why is diversity lost in the absence of a keystone predator in the diversity model? Question 6 options: A) Prey items compete for limited resources and due to Competitive Exclusion Principle one drives the others to extinction. B) Because if new species don't evolve, diversity is lost. C) Prey items experience an unbalanced ecosystem and extinction occurs at many levels. D) Because one less predator is one less species. That is less diversity.
A
Wolves have which of the following? Question 5 options: A) An indirect positive effect on Aspen trees. B) A negative effect on spruce trees which caused a positive effect on aspen trees. C) No effect on Aspen trees. D) A direct positive effect on aspen trees.
A
A chronosequence is Question 7 options: a "space-for-time" substitution where ecologists can see evidence temporal changes in space instead of time. the pattern of growth of a plant the pattern of extinction in a community the measure of time it takes a tree to mature
A "space for time" substitution where ecologists can see evidence temporal changes in space instead of time
The Ips beetle outbreak in the Colorado National Monument is the result of Question 4 options: a long term winner of co-evolutionary interaction a native species with outbreaks accelerated by warming climate an invasive species that causes regular harm an escaped ornamental species
A native species with outbreaks accelerated by warming climate
In 1969 Paine showed that Starfish (Pisaster) had what effect on other species? Question 1 options: A) Pisaster assured the sharing of resources and prevented extinction by making sure the other species shared resources evenly. B) Pisaster was easily out competed but its diversity increased in the presence of a keystone predator. C) as a predator Pisaster exerted top-down influence on the other species like barnacles and mussels and prevented superior competitor species from monopolizing critical resources. D) Pisaster acted as a top competitor herbivore that used up all the resources in the intertidal zone and drove many species to extinction.
As a predator piaster exerted top-down influence on the other species like barnacles and mussels and prevented superior competitor species from monopolizing critical resources
According to the Scitable article, what do predators do when their food supply becomes scarce? Question 12 options: A) move to new habitats B) switch to other less-desireable sources of food that are more costly to obtain. C) switch to eating each other D) increase their reproductive abillity in a last ditch effort to survive.
B
Ant-plant associations are expected to be more specialized when environmental conditions are _______ and resources are _______ Question 4 options: A) unstable, abundant B) stable, scarce C) stable, abundant D) unstable, scarce
B
Pollen grains Question 8 options: A) is a treasure trove of nutrition for all eukaryotes B) cannot be digested by most organisms C) is a sought after food source for most insects D) is very easily digested by mammals
B
The article states that experiments have shown that extinction has what effect on ecosystem processes? Question 7 options: A) increases the importance of ecosystem processes B) decreases ecosystem processes C) decreases the profitability of ecosystems D) increases the value of ecosystems
B
What does the Yucca Moth feed its babies? Question 9 options: A) caterpillars B) Baby Yucca seeds C) nectar D) Pollen
B
What is a symbiosis in ecology? Question 2 options: A) When two species are in a mutualism and living in close quarters B) When two species live together in the same structure. C) When two species are helping each other to survive D) When one species benefits from an interaction but not as much as in a mutualism.
B
Latex in milkweeds has which of the following properties? Question 9 options: Is primarily a nutritional defense against herbivores is mostly a chemical defense against herbivores is mostly a physical defense against herbivores is both a chemical and a physical defense against herbivores
Both chemical and physical
According the article, who killed the last two wolf pups in Yellowstone National Park in 1924? Question 4 options: A) A Grizzly Bear B) Hunters C) Park Rangers D) Trappers
C
As latitude decreases, species richness on islands Question 5 options: A) decreases B) stays the same C) increases D) we don't have enough data to know.
C
As the area of an island increases, the number of species on the island _____. Question 3 options: A) decreases B) may increase or decrease depending on the amount of colonization and extinction C) increases D) stays the same but niches become smaller
C
Compared to islands that are further away from the mainland, slands that are closer to the mainland tend to have Question 4 options: A) no pattern associated with distance to mainland. B) about the same number of species because it mostly depends on size and habitat number. C) more species D) fewer species
C
Extinction increases with the number of species because Question 7 options: A) islands closer to the mainland have less extinction. B) larger islands have lower extinction rates C) more species means more competition for resources and more competitive exclusion. D) there are more predators when there are more species and predators eat other species.
C
How would you describe flower nectar? Question 7 options: A) Mostly protein with a little sugar B) Mostly fats and oils C) mostly sugar with a little protein D) Just the right amount of protein for insects
C
In ant plant associations like the Acacia ant plant association described in class, ants live inside a ________ and trees produce ______ and _____. Question 3 options: A) the trunk, nectar, food bodies B) roots, leaves, sugar C) domatia, nectar, food bodies D) leaves, fruit, sap
C
In the Lovejoy study they showed that small rainforest fragments had Question 9 options: A) about the same % of species as larger fragments B) more insect species but fewer birds. C) fewer species than large fragments D) a healthy ecosystem but at a smaller scale
C
In the diversity model of keystone predation from lecture, what is the relationship between the predator and the species losing out the most in competition? Question 7 options: A) indirect negative. B) direct positive effect C) indirect positive effect D) direct negative
C
Leaf cutter ants eat Question 5 options: A) trees B) insects C) Fungus D) Leaves
C
The 100 year pattern of lynx and hare population cycles was collected from Question 10 options: A) biologists using exclosures to measure species interactions B) an EPA grant to study predator prey cycles C) the Hudson Bay fur Trading company D) ecologists at the turn of the century 1900
C
What is biogeography? Question 1 options: A) The study of the adaptations different species have to different habitats. B) the study of the history of the world and the species that have occupied it. C) the study of variation in species composition and diversity among geographic locations D) the study of the effect of geography on gene flow in populations
C
When two or more species partition a resource Question 4 options: A) it increases the size of niches B) it reduces intraspecific competition C) It reduces interspecific competition D) It changes the number of potential niches in the ecosystem
C
Which of the following must be true in order for a keystone predator to maintain diversity? Question 15 options: A) Prey must be showing logistic growth B) Predators must be focused on eating only the bad species of prey. C) The Competitive Exclusion Principle must be occuring for the prey species. D) Predators must be at carrying capacity
C
Question 1 (1 point) Based on the scitable article on herbivory, what do calcium oxalate crystals do to herbivores? Question 1 options: cause an immune response act like a poison cause muscle cramps cause painful kidney stones
Cause painful kidney stones
In plants, secondary compounds are Question 7 options: compounds that are only used for defence against herbivores compounds that are not recognized as having a role in primary metabolism compounds that are smaller than primary compounds compounds that are used only after the primary compounds are used up
Compounds that are not recognized as having a role in primary metabolism
According to the articke, species like the Saguaro Cactus in the Sonorran desert and the fig trees in the tropical rainforest are Question 3 options: A) Called keystone prey because lots of things feed on them. B) Driving many of the less common species to extinction via competitive exclusion. C) declining because of competition. D) Called keystone hosts because they provide habitat for a variety of other species.
D
Assume you observe that there are 3 species of woodpecker in a forest and they each have a different size bill and feed on different sized trees. Which of the following are plausible explanations for how this came to be? Question 8 options: A) The birds once had bills that were the same size, but due to competition, they specialized into niches and this allowed their coexistence preventing extinction via CEP. B) The birds immigrated from elsewhere and already had different sized bills. Because they already partitioned resources they didn't compete and didn't drive each other to extinction via CEP. C) Many species colonized the forest and had a diversity of bill lengths. Those species that had similar bill lengths competed and drove many to extinction. Only those that didn't compete persisted. Now the only ones that persist were those that were not in competition. D) all of the above are plausible.
D
Competition theory suggests that coexistence can occur when Question 3 options: A) two species occupy the exact same niche B) interspecific competition is stronger than intraspecific competition C) The logistic growth equation is in full effect. D) intraspecific competition is stronger than interspecific competition
D
Consider an example where 2 closely related species of warbler exist in the same forest. One of them forages on branch tips with its tiny bill, and other forages on the tree trunks with a much larger stout bill. What do we have evidence to support of the following statements? Question 9 options: these species are specialized because it reduces competition. the two species are better off because of competition The two species were once one species but speciated due to a need for reduced competition there is reduced competition between the two species due to niche specialization
D
The article suggests plants may not show resource partitioning as much as animals because Question 5 options: A) Plants are not likely to show resource partitioning because they cannot move. B) Plants are more likely to show resource partitioning because they can't move. C) Plants actually show more resource partitioning than animals because they are involved in more interactions. D) They all require a limited suite of resources so there isn't much room for partitioning.
D
The bacteria that grows on the leaf cutter ants has what kind of effect on the fungus they harvest? Question 6 options: A) direct negative B) direct positive C) indirect negative D) indirect positive
D
The definition of a mutualism in ecology is Question 1 options: A) It is best described as a give an take where one species gives and expects the other to take something. B) An interaction in which at least one species has a reduction in survival and reproduction so that another species may co-exist C) An interaction in which two species sacrifice themselves to help each other D) An interaction in which both species receive a net benefit from the interaction
D
The edge effect is what happens when Question 10 options: A) Species on the coastal edge of islands fall off into the ocean and don't return B) Species share a territory boundary and share the niche. C) Studies are performed in very small plots and researchers fail to notice the boundary line. D) Forest on the edge of a reserve is influenced (often degraded) by biotic and abiotic factors.
D
The rate of extinction increases with the number of species on an island because Question 8 options: A) More species are found in the tropics and tropical species can't persist as easily on islands B) more species means more niches and many of those niches will disappear with changing climate. C) more species means greater environmental stochasticity which reduces the survivorship of all species. D) More species means smaller populations of each species and increased demographic stochasticity and allee effect
D
Would you consider the Yucca/Yucca Moth interaction to be Question 10 options: A) commensal B) facultative C) Parasitic D) Obligate
D
The Piper plant in the Ecuador research had some compounds that were fed to caterpillars from the US. What happened to the caterpillars? Question 6 options: they grew faster than expected they grew slower than expected They died they developed an immune response
Died
Ecological Succession is Question 6 options: the order of organisms from most abundant to least abundant directional, predictable change in community structure over time parents making offspring that inherit their traits
Directional, predictable change in community structure over time
Tilman's Resource Ratio Hypothesis Predicts that Question 10 options: soil organisms are the most important part of succession resources are limiting only in late succession early successional plants compete for nutrients but late successional plants compete for light mycorrhizae are the most important part of succession.
Early successional plants compete for nutrients but late successional plants compete for light
Based on the Scitable article on herbivory, what do some plants do to avoid apparency? (I'm not sure I really agree with this one so please be skeptical. Nonetheless... Question 2 options: Grow very large grow in large numbers grow in isolated locations grow with bright colors
Grow in isolated locations
The BobTail Squid allows only Vibrio fisheri into its organ using what technique? Question 4 options: it secretes a chemical cocktail that is hostile to all but V. fisheri. it uses pinocytosis and a cell signalling protein to recognize them it has tiny pores in its skin that are exactly the size of the V. fisheri It eats all kinds of bacteria and its immune system kills everything else.
It secretes a chemical cocktail that is hostile to all but V.fisheri
When mange parasites reduced the red fox population in Sweden, what happened to their prey the voles? Question 13 options: A) Voles continued cycling unchanged B) voles decreased in population size C) voles increased in population size D) voles stopped cycling altogether and became stable at K.
NOT: voles stopped cycling altogether and became stable at K. OR voles increased in population size
The Competitive Exclusion Principle states
No two species can occupy the same niche indefinitely, one will drive the other to extinction
What category would you place trichomes? Question 3 options: nutritional defence latex defence chemical defence physical defence
Physical
Facilitation is when Question 8 options: species alter the environment making it better for other species to colonize species help one another succeed one species loses competition and another wins a species "gives up" its spot to another species
Species alter the environment making it better for other species to colonize
Niche
The resources a species requires for survival and reproduction
If one considers the different parts of plants Question 8 options: toxins and nutrition are generally unrelated They vary in the nitrogen available to herbivores toxins are fairly evenly distributed they are all pretty much the same nutritionally
They vary in the nitrogen available to herbivores
Researchers investigating the Piper plant in Ecuador found which of the following? Question 5 options: a new species of millipede that eats leaves the same chemical compounds that are found in oak trees in the US Three new chemical compounds to science roots with extraordinarily small rootlets in rainforest soil
Three new chemical compounds to science
The realized niche is always smaller than the fundamental niche. Question 10 options:TrueFalse
True
Which of the following are likely to increase the intensity of Ips beetle outbreaks? Question 10 options: shorter warmer winters drought longer warmer summers all of these answers can increase the intensity of Ips beetle outbreaks
all
In general, how does diversity change as succession progresses? Question 9 options: diversity decreases diversity increases diversity is independent of successionary stage
diversity increases
The video suggests the greatest risk of mortality to BobTail Squids is Question 2 options: viruses Predation bacteria starvation
predation
The Bobtail Squid uses a light organ Question 3 options: that makes small amounts of light that attract bacteria that only produces light when if it is occupied by bacteria that makes more light if it has bacteria, but still works without them. that kills bacteria to make a glowing light
that only produces light when it is occupied by bacteria
Which of the following describes the effects of the bacteria on the light organ? Question 5 options: the bacteria occupy the organ but don't cause it to change The bacteria cause necrosis, opening a pale hole in the skin. The bacteria occupy the organ and cause a single light producing tissue to be made the bacteria cause a multi-tissue light organ to develop
the bacteria cause a multi-tissue light organ to develop
The BobTail Squid is about the size of Question 1 options: a car an orange a walnut a basketball
walnut
