Which of the following variations might provide a survival advantage? (You may select more than one)
A.
White fur
B.
Sharp eyesight
C.
A great sense of smell
D.
A longer tail
A, B, and C
A random genetic mutation results in white fur. What would you expect this population to look like after several hundred years
A.
Mostly wolves with normal fur
B.
Mostly wolves with white fur
C.
An equal combination of the two
D.
The wolves would go extinct
B. Mostly wolves with white fur. Over time, the white fur allele would spread throughout the population through natural selection if it provided a survival advantage in their environment.
Fill in the blanks.
In a pine forest, a population of grey ______ live among the trees and hop from tree trunk to tree trunk. A random _______ results in a brown fur color which closely matches the brown tree trunks. After several hundred years the fur color becomes the most ______ because it provides the ______ of camouflage and it is difficult for ________ to see them.
In a pine forest, a population of grey squirrels live among the trees and hop from tree trunk to tree trunk. A random mutation results in a brown fur color which closely matches the brown tree trunks. After several hundred years, the fur color becomes the most common because it provides the advantage of camouflage and it is difficult for predators to see them.
A bottleneck event can be caused by (mark all that apply)
A.
Environmental disasters
B.
Disease epidemics
C.
Habitat destruction
D.
Over exploitation (including things like hunting and fishing)
A, B, C, and D.
All of 'em?
Yes, all of them: environmental disasters, disease epidemics, habitat destruction, and overexploitation can lead to a bottleneck event.
A small population of deer live on an island. A natural disaster kills a large portion of their population.
Why is this a challenge to this population?
A.
Because now there is not enough food for all the deer
B.
Because now the gene pool is reduced and even disadvantageous traits will be passed to offspring
C.
Because it is very sad for the deer population
D.
Because now the deer population will be threatened due to low genetic variation
D. Because now the deer population will be threatened due to low genetic variation. With a reduced population, the genetic diversity of the population is also reduced. This means that there is a higher chance of inbreeding and a greater possibility of harmful genetic mutations being passed on to future generations. Therefore, the small population is at risk of genetic drift, in which the frequency of rare alleles might change drastically over time, leading to a homogenization of their gene pool and the potential loss of genetic information that could be key to their adaptation and survival in the long run.
There is a population of lizards that differ in size and in diet. The large sized lizards eat plants while the small sized lizards eat insects. Climate change is affecting the habitat of these lizards. Excessive rains have been helpful for the plants but have drowned many of the insects and killed their larvae. What is the selective pressure that is affecting this population of lizards?
A.
The large body size of the lizards
B.
The small body size of the lizards
C.
The plant population
D.
The insect population
D. The insect population. The excessive rains and subsequent flooding have negatively impacted the insect population, which is the main source of food for small lizards. This creates selective pressure on the lizards with a smaller body size, as their survival is threatened by the loss of their primary food source. On the other hand, the large lizards that eat plants have a more stable food source with the increase in plant population due to the excess rain. However, this may indirectly impact their survival if the population of small lizards declines, which would lead to a decrease in their food source, as well as a still further reduction of the available insects for other insect-eating animals in the ecosystem.
Can you explain WHY the correct answer for the previous question was ‘The insect population?”
A.
Because the abundant numbers of plants are causing some lizards to die
B.
Because the low numbers of insects are causing some lizards to die
C.
Because the environment is not in balance
D.
I have no idea
The correct answer is B. Because the low numbers of insects are causing some lizards to die. Climate change has affected the habitat of these lizards, leading to excessive rains that have killed many of the insects and their larvae. This creates a selective pressure on the lizards with a smaller body size, as their survival is threatened by the loss of their primary food source. The decrease in the insect population also affects other insect-eating animals in the ecosystem, resulting in potential declines in populations of these animals, too. Therefore, shifts in the availability of resources like insects can create selective pressure in the populations that depend on them, altering the balance of the ecological community over time.
There is a population of lizards that differ in size and in diet. The large sized lizards eat plants while the small sized lizards eat insects. Climate change is affecting the habitat of these lizards. Excessive rains have been helpful for the plants but have drowned many of the insects and killed their larvae. Which set of lizards will be the most impacted by the low availability of insects?
A.
The large lizards
B.
The small lizards
C.
Both sets of lizards
D.
Neither set of lizards
B. The small lizards. The low availability of insects due to excessive rain will affect the population of small lizards the most since they depend mostly on insects for their food. In contrast, the large lizards, which primarily eat plants, would do better because the plants grow better due to the excessive rain. Therefore, the small lizards are expected to suffer a higher mortality rate than the large ones because the loss of their primary food source directly affects their growth, survival, and reproduction.
Fill in the blanks.
On a distribution curve if the ______ of the peak is to the ______ that indicates that the ______ got An example of this could be the shift in ______ size of ancient ______ to modern day ______.
On a distribution curve, if the shift of the peak is to the left, that indicates that the population got smaller. An example of this could be the shift in body size of ancient humans to modern-day humans.
Fill in the blanks.
On a distribution curve that is shifted to the ______ we can tell that the ______ got an example of this is the shift in the neck ______ of ancient ______ to modern day ______.
On a distribution curve that is shifted to the right, we can tell that the population got larger. An example of this is the shift in the neck length of ancient giraffes to modern-day giraffes.
Select the TRUE statements from the following:
A.
Nature and humans have both created very similar types of organisms
B.
Nature selects for variations that help an organism survive
C.
Humans select for variations that help an organism survive
D.
Humans select for variations that provide an advantage for humans
B. Nature selects for variations that help an organism survive, and C. Humans select for variations that help an organism survive, are true statements from the options.
A. Nature and humans have both created very similar types of organisms: This statement is not true because nature and humans have different mechanisms of creating organisms.
D. Humans select for variations that provide an advantage for humans: This statement is not entirely true because humans don't always select variations that provide an advantage for humans, rather they may select traits that are desirable for certain purposes, such as aesthetics or convenience, which do not necessarily provide a direct advantage for humans in a rigorous sense.