C. drought
The main selective pressure in this scenario is the drought, as it is directly impacting the availability of resources for the bird population. The drying up of ponds and decline in fish populations is causing a shift in the availability of food sources for the birds, leading to potential changes in the survival and reproduction of individuals with different traits (such as leg length and diet preferences). This change in environment is likely to drive natural selection in favor of individuals best adapted to the new conditions.
Consider the following scenario:
A drought hits the habitat of a semi-aquatic bird population. All ponds dry up, and fish populations decline. There are two groups of birds in the population that differ in leg length and diet. Long-legged birds eat fish, while short-legged birds eat insects. The drought has little effect on insect populations.
What is the main selective pressure in this scenario?
A. fish population
B. leg length
C. drought
D. insect population
11 answers
Which statement is accurate about variations?
A. Organisms with variations that give an advantage are more likely to survive.
B. Organisms with variations are less likely to pass these variations to their offspring.
C. In all cases, variations become more common in a population.
D. In all cases, variations affect how likely it is that an organism reproduces.
A. Organisms with variations that give an advantage are more likely to survive.
B. Organisms with variations are less likely to pass these variations to their offspring.
C. In all cases, variations become more common in a population.
D. In all cases, variations affect how likely it is that an organism reproduces.
A. Organisms with variations that give an advantage are more likely to survive.
This statement is accurate as it reflects the concept of natural selection, where individuals with advantageous variations are more likely to survive and reproduce, passing those beneficial traits to their offspring. Over time, this can lead to the spread of these advantageous variations within a population.
This statement is accurate as it reflects the concept of natural selection, where individuals with advantageous variations are more likely to survive and reproduce, passing those beneficial traits to their offspring. Over time, this can lead to the spread of these advantageous variations within a population.
Consider the following scenario:
In a muddy lake environment, some fish have brown scales. Most fish, however, have silver scales. Predators have a harder time seeing the fish with brown scales.
Which term best describes the brown scales?
A. inactivated gene
B. new mutation
C. advantageous trait
D. predominant phenotype
In a muddy lake environment, some fish have brown scales. Most fish, however, have silver scales. Predators have a harder time seeing the fish with brown scales.
Which term best describes the brown scales?
A. inactivated gene
B. new mutation
C. advantageous trait
D. predominant phenotype
C. advantageous trait
The brown scales would be considered an advantageous trait in this scenario because they provide a camouflage advantage to the fish, making them less visible to predators in the muddy lake environment. This trait increases the likelihood of survival for the fish with brown scales, making it advantageous in terms of natural selection.
The brown scales would be considered an advantageous trait in this scenario because they provide a camouflage advantage to the fish, making them less visible to predators in the muddy lake environment. This trait increases the likelihood of survival for the fish with brown scales, making it advantageous in terms of natural selection.
How did the Industrial Revolution impact the population of peppered moths in Britain?
A. The Industrial Revolution caused the proportions of each color morph in the population to become equal.
B. The light-colored moths became more common.
C. The dark-colored moths became more common.
D. The Industrial Revolution caused the proportions of each color morph in the population to become unequal.
A. The Industrial Revolution caused the proportions of each color morph in the population to become equal.
B. The light-colored moths became more common.
C. The dark-colored moths became more common.
D. The Industrial Revolution caused the proportions of each color morph in the population to become unequal.
C. The dark-colored moths became more common.
During the Industrial Revolution in Britain, pollution from factories darkened the tree trunks, which provided better camouflage for the dark-colored peppered moths. As a result, the dark-colored moths became more common in the population as they had a higher survival rate than the light-colored moths against predation. This phenomenon is often cited as an example of natural selection in response to environmental changes.
During the Industrial Revolution in Britain, pollution from factories darkened the tree trunks, which provided better camouflage for the dark-colored peppered moths. As a result, the dark-colored moths became more common in the population as they had a higher survival rate than the light-colored moths against predation. This phenomenon is often cited as an example of natural selection in response to environmental changes.
There are two varieties in a population of squirrels: short tails and long tails. Long-tailed squirrels are better at jumping and balancing in trees. Scientists observe that over the span of 100 years, the proportion of the population with long tails increases from 10% to 60%. Which statement is most likely?
A. The proportion of long-tailed squirrels may have increased due to increased food availability.
B. The proportion of long-tailed squirrels may have increased due to a decrease in trees.
C. The proportion of short-tailed squirrels may have decreased due to an increase in trees.
D. The proportion of short-tailed squirrels may have decreased due to decreased food availability.
A. The proportion of long-tailed squirrels may have increased due to increased food availability.
B. The proportion of long-tailed squirrels may have increased due to a decrease in trees.
C. The proportion of short-tailed squirrels may have decreased due to an increase in trees.
D. The proportion of short-tailed squirrels may have decreased due to decreased food availability.
A. The proportion of long-tailed squirrels may have increased due to increased food availability.
If long-tailed squirrels are better at jumping and balancing in trees, they may have easier access to food sources like fruits and nuts in trees compared to short-tailed squirrels. This advantage could lead to increased survival rates and reproductive success for the long-tailed squirrels, ultimately resulting in a higher proportion of long-tailed individuals in the population over time.
If long-tailed squirrels are better at jumping and balancing in trees, they may have easier access to food sources like fruits and nuts in trees compared to short-tailed squirrels. This advantage could lead to increased survival rates and reproductive success for the long-tailed squirrels, ultimately resulting in a higher proportion of long-tailed individuals in the population over time.
Why is the cheetah gene pool small today?
A. lack of advantageous traits
B. multiple bottleneck events
C. poor adaptability
D. inbreeding in zoos
A. lack of advantageous traits
B. multiple bottleneck events
C. poor adaptability
D. inbreeding in zoos
D. inbreeding in zoos
The cheetah gene pool is small today primarily due to inbreeding in zoos. In captive breeding populations, there is often a limited number of individuals, which can result in inbreeding when closely related individuals are bred together. Inbreeding can lead to a reduction in genetic diversity, an increased expression of deleterious traits, and a higher susceptibility to diseases. In the case of cheetahs, inbreeding in zoos has contributed to the small gene pool and genetic issues seen in the population.
The cheetah gene pool is small today primarily due to inbreeding in zoos. In captive breeding populations, there is often a limited number of individuals, which can result in inbreeding when closely related individuals are bred together. Inbreeding can lead to a reduction in genetic diversity, an increased expression of deleterious traits, and a higher susceptibility to diseases. In the case of cheetahs, inbreeding in zoos has contributed to the small gene pool and genetic issues seen in the population.
2 answers