Question 1

Following their respective breeding seasons,several species of hummingbirds occur at the same locations in North America and several hummingbird flowers bloom simultaneously in these habitats.These flowers seem to have converged to a common morphology and color.Birds are most visually sensitive to the color red.Hummingbird flowers are pollinated by hummingbirds.Which of the following features of these flowers would indicate they have coevolved with hummingbirds? (Check all that apply)

Accepted Answer

The long tubular shape of the flowers is an adaptation to the long, narrow beaks of hummingbirds, allowing them to reach the nectar deep within the flower. The blooming time coinciding with the hummingbird arrival suggests a coevolutionary relationship, where the birds are driving the timing of the flowers' reproduction. The high volume of nectar and sugar in the flowers is also an adaptation to the high metabolic demands of hummingbirds, who require a lot of energy to sustain their high levels of activity. The color violet and blue is not as important since birds are most visually sensitive to the color red, which is the color of many hummingbird-pollinated flowers. The height of the flowers is not as important since hummingbirds are capable of hovering in mid-air to reach flowers at different heights.

Question 2

Interspecific competition can affect the phenotypic characteristics of organisms.

Accepted Answer

Interspecific competition involves two different species competing for the same resources, which can affect the phenotype of the competing individuals as they evolve to have traits that help them better compete.

Question 3

Geographical allopatry between species is definitive evidence of interspecific competition.

Accepted Answer

Geographical allopatry simply means that two species inhabit separate areas and do not overlap. This by itself is not definitive evidence of interspecific competition. Other factors such as differences in niche utilization or physical barriers may also play a role in determining species distributions.

Question 4

Adaptation that enables organisms to blend into their environment thereby avoiding predation.

Accepted Answer

The answer of Adaptation that enables organisms to blend into...

Question 5

Garlic mustard is an invasive plant species in North American temperate forests.Garlic mustard secretes an allelochemical that interferes with relationships between native tree roots and their mycorrhizal fungi.This would be an example of

Accepted Answer

Garlic mustard secreting an allelochemical that interferes with the relationships between native tree roots and their mycorrhizal fungi is an example of interference competition, as it directly interferes with the ability of other plant species to establish and maintain relationships with mutualistic fungi. Exploitative competition involves one species getting access to resources faster, leaving less for other species, but in this case, garlic mustard is actively inhibiting other species' access to resources.

Question 6

Following their respective breeding seasons,several species of hummingbirds occur at the same locations in North America and several hummingbird flowers bloom simultaneously in these habitats.These flowers seem to have converged to a common morphology and color.Birds have the most visual sensitivity to the color red.Following their breeding season,these species of hummingbirds are

Accepted Answer

The fact that several species of hummingbirds occur at the same location and several hummingbird flowers bloom simultaneously in these habitats suggests that they are sympatric, meaning they share the same geographic location and coexist. The convergence of flower morphology and color could be a result of coevolution with the hummingbirds, who have visual sensitivity to the color red, and their presence in the same habitat.

Question 7

Which of the following statements about mimicry are true? Check all that apply.

Accepted Answer

Option C is true as in Müllerian mimicry, both the participants act as models and mimics. Option D is also true as in Batesian mimicry, the participants can either be mimics or models. Option A is false as the number of mimics in a Müllerian mimicry system can be greater than the number of models. Option B is false as both Batesian and Müllerian mimicry depend on the predator's ability to learn. Option E is a false and irrelevant statement.

Question 8

Which of the following statements about symbiotic relationships are true? Check all that apply.

Accepted Answer

A) Plant-pollinator interaction is an example of mutualism as both the plant and the pollinator benefit from the interaction.
B) This statement is partially true. Coevolution may lead to the development of both mutualisms and commensalisms, but not all of them arise from this process.
C) It can be challenging to determine whether a specific relationship is mutualism, commensalism, or parasitism because the benefits and harm vary among organisms.
D) Parasites can alter a host's behavior to support their life cycles, such as causing them to behave in ways that increase the likelihood of transmitting the parasite.
E) Mutualists can evolve to become parasites if they derive more benefits from exploiting their partner than from maintaining a mutually beneficial relationship.

Question 9

In general,communities in early succession will be dominated by fast-growing species with r-selected life histories.

Accepted Answer

This is because these species have a high reproductive rate, short life span, and are able to quickly colonize and establish themselves in new habitats. As succession progresses, slower-growing and more competitive species with K-selected life histories may become dominant.

Question 10

Which of the following statements about the intermediate disturbance hypothesis are true? Check all that apply.

Accepted Answer

The answer of Which of the following statements about the...

Question 11

Chemical compounds produced by plants that are not components of major metabolic pathways.

Accepted Answer

The answer of Chemical compounds produced by plants that are...

Question 12

In which habitat would you expect to encounter community assemblages that are most similar?

Accepted Answer

Freshwater streams in North America and Europe would have similar environmental conditions such as water temperature, flow, and nutrient levels, which would lead to similar biological communities. In contrast, the other habitats listed have drastically different environmental factors that would lead to very different community assemblages.

Question 13

Forests,like other ecological systems,are subject to the species succession process.Which of the following would be characteristics of pioneer plant species facilitating the early stages of forest succession? (Check all that apply)
A)slow-growing
B)pollinated by animals
C)seedling growth requires direct sunlight
D)seeds germinate in the shade
E)plants produce great quantity of seeds

Accepted Answer

The answer of Forests,like other ecological systems,are subject to the...

Question 14

Mimicry is a form of camouflage.

Accepted Answer

Mimicry is a form of camouflage where an organism camouflages itself by looking like another organism or inanimate object.

Question 15

Resource partitioning would be most likely to occur between allopatric populations of species with similar ecological niches.

Accepted Answer

Resource partitioning typically occurs between sympatric populations of species with similar ecological niches, as they live in the same geographic area and directly compete for resources, leading to niche differentiation.

Question 16

Communities with a high level of bacterial diversity are found in many habitats including soil and aquatic environments.Recent studies indicate this diversity is crucial to the functioning of these communities.The same studies have also found that phage abundance plays a critical role in the maintenance of the bacterial diversity within these communities.Are phages a density-dependent or a density-independent regulating factor?

Accepted Answer

Density-dependent regulating factors are those in which the impact of the regulating factor depends on the density of the population. In this case, phages are considered density-dependent because they have a greater impact on bacterial diversity and community functioning when the bacterial population is higher.

Question 17

When there are high levels of disturbance in a community,the number of K-selected species should increase along with the overall diversity of the community.

Accepted Answer

High levels of disturbance typically favor r-selected species, which have high reproductive rates and can quickly colonize disturbed habitats. K-selected species, which have slower reproductive rates and are adapted to stable environments, may struggle to compete in disrupted ecosystems. Therefore, the number of r-selected species may increase while the number of K-selected species may decrease in disturbed communities. Overall diversity may also decrease as disturbance can lead to the loss of specialized species and the dominance of generalist species.

Question 18

It is a situation in which a palatable organism resembles another kind of organism that is distasteful or toxic.

Accepted Answer

The answer of It is a situation in which a...

Question 19

Which of the following statements about predation are true? Check all that apply.

Accepted Answer

The answer of Which of the following statements about predation...

Quiz 55: Community Ecology