Ecology Final 2024 TXST

Heirarchy of ecological systems

individual, population, community, ecosystem, biosphere

Which of the following systems is composed of assemblages of organisms together with their physical and chemical environments?

Ecosystem

Dynamic steady state

State in which there is no net change between inputs and outputs

Interaction in which both species involved are negatively impacted

Competition

Why is the bottom of a temperate lake typically close to 4C year-round

Water is densest at 4C

Energy of incident solar radiation reaching the surface of Earth declines toward the poles from its maximum in equitorial regions. Which of these is NOT a reason for this

Tilt of the Earth increases the reflection of solar radiation

Where is the solar equator

between 23.5º S and 23.5º N of the equator, depending on the season

On a climate diagram, the growing season of a biome occurs when the

Tempurature is above 0C

What process creates new alleles in a population

mutation

Stickleback fish exhibit variation in a morphological trait known as gill rakers. Fish with long gill rakers are very good at eating plankton, and fish with short gill rakers are good at eating deep-water invertebrates. However, fish with intermediate-length gill rakers are poor at eating either type of food. Fish that are better at consuming food have higher survival and reproduction rates than poorer consumers. Based on this information, what type of selection is likely acting on stickleback gill raker length?

disruptive selection

Which is correct about the founder effect?

I: Founder effect occurs when infividuals are transplanted to a new location

II: Founder effect produces new alleles

III: Founder effect may see a firther reduction in genetic variation

I and III

When a phenotype is under disruptive selection, which parts of the phenotypic distribution are expected to have the highest fitness?

individuals when both extremely large and extremely small values of the phenotype

Grime proposed that combinations of life history traits in plants are mainly determined by three factors. What are these three factors?

Disturbance, competition, stress

Consider a species with a slow potential growth rate, reproduction at a relatively late age, allocation of a small proportion of net production to seeds, and reliance of vegetative spread. According to Grime's classification of life history traits, this speceis fits the profile of a

Stress tolerator

Having a large number of offspring potentially affects a parent's fitness for subsequent breeding seasons. Which of the following outcomes is the LEAST likely?

Competition with offspring for food could reduce energy for future reproduction

Red foxes mature after their first year of life and may live for 5 to 10 years. Foxes often reproduce many times over their life. The term to describe this aspect of their life history is

iteroparous

In honeybees, drone arise from ---- eggs, and workers arise from ---- eggs

unfertilized haploid; fertilized diploid

The production of offspring from the nonsexual tissue of a parent is called

vegetative reproduction

Which statement best describes Red Queen hypothesis

Sexual reproduction allows organisms to increase survival by keeping up with the evolution of parasites

Which describes a plant species with with perfect flowers?

Individual plants have flowers that contain both female and male structures

Difference between herbivory and predation

Herbivory keeps the plant alive while predation kills

Why must communities in intertidal zones be adapatable to a wide range of conditions

Tempurature and salt concentration are ever changing

Bogs vs. Marshes vs. Swamps

Bogs: acidic, mossy, nutrient poor

Marshes: grassy, nonwoody vegetation, shallow, tidal

Swamps: forested, emergent trees, stagnant water

Similarities and differences between tropical rainforests and tropical seasonal forests

Similarities: steady tempuratures, growth season throughout the year

Differences: rainforests have high precipitation levels, thick canopy, and highest biodiversity, seasonal forests have lots a grazing and predatory mammals and a dry season

Why is monogamy more frequently seen in birds than mammals?

Males offer the same care as females in bird species but not in mammal species

Animals that live in groups have a reduced probability of predation. This is known as

the dilution effect

Large groups are particulartly vulnerable to parasites and pathogens because they

can rapidly become infected by a single individual

Why is altruistic behavior an evolutionary problem?

it does not lead to an increase in direct fitness

An endangered frog species lives in only a few forest patches found throughout the Pacific Northwest of the United States. The Pacific Northwest is its _____ and the forest patches are its _____.

geographic range, realized niche

The orange-breasted sunbird (Anthobaphes violacea) lives only in the fynbos region in the Western Cape of South Africa. This is an example of

endemic species

Ants should live in _____ populations, and rhinoceroses should live in _____ populations.

high density, low density

According to an exponential growth population model, when the number of births is less than the number of deaths,

r < 0

Which illustrates a negative relationship between population density and the average size of individuals over time?

a self-thinning curve

The larvae of a carnivorous species of salamander inhabit ponds. When the pond contains few larvae, they mostly eat small invertebrates and have a high survival rate. When there are many salamander larvae in a pond, the larvae will also cannibalize each other and have a low survival rate. This is an example of

negative density dependent population regulation

In the logistic growth model, which term determines how quickly a poopulation will initially grow from low density?

r

In population dynamics following the logistic model, an overshoot occurs when

N > K

In the logistic growth model that includes delayed density dependence, the term m indicates the

length of the time delay

For populations growing under the logistic growth model with delayed density dependence, which of the following combinations of parameter values is most likely to lead to damped oscillations

0.37 < rτ < 1.57

Which statement correctly identifies the relationship between population size and extinction rate?

Small populations are most likely to go extinct

Which of the following is NOT a factor that determines whether a patch is likely to be occupied by a species?

history of extinction in the patch

In Lotka-Volterra predator-prey models, prey populations decrease when

P > r/c

At the joint equilibrium point,

both predator and prey populations have zero growth

Which characterizes the rate of infection between suseptible and infected individuals in an S-I-R model

b x I x S

White-nose syndrome in North American bats is an example of a parasite that was likely transmitted by

horizontal transmission

What is the overall message of "From Ants to Grizzlies: A General Rule for Saving Biodiversity"

A larger, more connected area will support more species

The range of abiotic conditions a species can persist in

fundamental niche

Animals living packs, such as wolves, establish an order that dictates social behavior. This is an example of

dominance heiarchy

A hummingbird guarding a hummingbird feeder is an example of

territory

In some parts of the United States, pathways for wildlife are built over or under highways to allow animals to cross safely. This is an example of a

habitat corridor

That individuals are more likely to find mates and reproduce when populations are larger compared to when populations are smaller might be termed the

allee effect

Consider moose that breed in the fall and give birth in the spring. During breeding, the moose population is below carrying capacity, but once the young moose are born, the moose population far exceeds carrying capacity. This is an example of

delayed density dependence

The females of a certain species of fish produce on average 1,000 eggs each year. By chance, some females produce a few more eggs than average, and others produce slightly fewer eggs than average. This is an example of

demographic stochasticity

Human activity can affect metapopulation by affecting colonization and extinction. Under the basic model of metapopulation synamics, when humans make it easier for infividuals to travel between patches, the probability of ____ ____ and the proportion of occupied patches ______

colonization increases, increases

Human activity can affect metapopulations by affecting colonization and extinction. In the basic model of metapopulation dynamics, if humans imporve habitat quality (and thus carrying capacity) of subpopulations, the probability of ____ ____ and the proportion of occupied patches ____

extinction decreases, increases

The ability of a host to prevent infection by parasites is called

Resistance

The age structure of a population is often represented by a pyramid. What does an age structure pyramid with a broad base and a narrow top indicate about a population? What is happening to the population?

The population is growing

Endoparasites seem to lead an ideal life in the interior of the host, protected from naturalenemies and the external environment while having a continual supply of nutrients. What are the challenges endoparasites face

Host immune system and difficulty spreading between hosts

Unlike predators, most parasites do not kill their hosts. Why is this beneficial

Parasites require their hosts to live

What is the difference between fundamental and realized niche

Fundamental niche does not include biotic factors

What is the difference between positive and negative density dependence

Positive: higher density, higher growth

Negative: higher density, lower growth

Patch A has 200 individuals. Patch B has 600 individuals. Patch C has 50 individuals. Which is most likely to go extinct

Patch C

What is the difference between Batesian and Mullerian Mimicry

Batesian: paletable organism copying unpaletable organism

Mullerian: nonpaletable organism copying unpaletable organism

Why are parasites that use horizontal transmission suseptible to environmental stochasticity

The parasite must be exposed to the environment for some amount of time in order to perform horizontal transmission, meaning they can be affected by random changes in the environment

What did the Wildlife Trust of India do in order to relieve the conflicts between migrating elephants and human residents?

They relocated the residents out of the elephant migration corridors

Intraspecific competition occurs when

Individuals of the same species compete with each other

What is an example of a nonrenewable resource

space

Leibig's Law of the Minimum fails to consider what

fails to consider competition for resources

If you removed mutualistic ants from acacia trees, there would be

more herbivorous insects on the acacia

If ants are removed from aphids when and they are in a mutualistic relationship, what will likely happen

More aphids will be eaten

The association between bees and flowering plants is a well known mutualism. What benefit do bees proide flowering plants

Bees spread pollen from one flower to the next

How does an ecologist determine the presence of an ectone

Measure the abundance of plant species over space and abrupt changes in species competition

What communtiy measure does Shannon's index quantify

species diversity

What is an example of an ecosystem engineer

beavers, which build dams on streams

How would radioactive carbon bubbled into an aquarium travel through trophic levels

producers -> herbivores -> carnivores

What is a major distinction between direct and indirect effects in a community

indirect effects always include more than two species; direct effects do not

A pioneer species is ____ species to arrive at a site

the first

Why were wind- and sea-dispersed seeds that first to colonize and survive on Krakatau

In the early days of colonization, there were no forests to attract animals that could disperse seeds

Which of the following is NOT an example of a habitat that could undergo primary succession

tree-fall gap

The equilibrium theory of island biogeography states that the number of species on an island reflects a balance between

colonization of new species and extinction of existing species

Which of the folling is NOT an effect of fragmentation of a large contiguous habitat

the amount of edge habitate decreases

In which biogeographic region is Egypt

Palearctic

Provisioning service are those that

humans use, including lumber, fur, meat, crops, water, and fibers

In the study of stream sucession following a major flood event at Sycamore Creek in Arizona, what was the first organism to recolonize the stream

Diatomes

When seeds of early and late succession species were raised under low light conditions similar to those found in the understory of a mature forest, researchers found that species with ____ seeds has ____ seedling survivorship in shade

A long-lasting influence of historical processes on the current ecology of an area is called a ____ effect

legacy

As habitat heterogeneity ____, species diversiy ____

increases, increases

The development of communities in habitats that are initially devois of plants and organic soil is known as ____ succession

primary

In Lotka-Volterra population models, a12 and b21 are referred to as

competition coefficients

Imagine that an acacia tree in the anti-plant mutualism is introduced to an island without ants. Over evolutionary time, natural selection from the lack of ants would probably lead to acacia trees that produce ____ nectar

less

Biotic ____ is the process by which unique species compositions originally found in different regions slowly become more similar as a result of the movement of people, cargo, and species

homogenization

The goal in protecting a habitat is commonly the preservation of a large enough area to support a ____ ____ population.

minimal viable

According to the IUCN (2017), which group is the most threatened or near-threatened with the risk of future extinction globally

amphibians

What is guano and why was it valuable. Why must the biodiversity of the region be studied prior to extraction

Guano has a high concentration of nitrogen and is difficult to extract. Ecologists must make sure that nothing in the region relys on the guano.

How can predation increase prey species richness and eveness in a community

Predators can cull highly competitive herbivores

What are omnivores and how does a high presence of them affect food webs

Animals that consume plants and animals, make food webs more complex

What is the findings of the goldenrod fields