Question

can you answer these
In the African savanna, more wildebeests are born than the environment can support. Which is most likely to happen over a period of years as a result?
The chances for survival of the population are reduced.
New food sources are discovered and become the regular diet.
Individuals that are well suited to the environment reproduce, and those that are not well suited die before they reproduce.
The environment adapts by providing more resources to the growing population, increasing the chances of survival for individuals within the habitat.

During a trip to the Galapagos Islands, which observation led Charles Darwin to suspect that organisms change over time?
Island finches were able to breed with mainland species.
Island finches resembled mainland finches, but were not the same species.
Island finches resembled extinct species from other islands around the world.
Island finches did not have beaks of the same size and shape.

Charles Darwin observed a unique beak size and shape in the finch population of each of the Galapagos Islands that he visited.

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Which is the most likely cause of the observed variation?
differences in the climate among the islands
competition among individuals for available food sources
competition among individuals for desirable mates
differences in egg size among the populations

Which organism exhibits behavioral adaptation?
an owl with large pupils and eyes that enable it to see better at night
a possum playing dead to increase its chances of survival
an insect that mimics its environment to hide from its predators
a desert plant that sheds its leaves to lessen water loss during the dry season

A population of rabbits has individuals with fur coloring that ranges from white to brown. The population lives in a temperate deciduous forest where the summers are mild and average about 50°F. The winters are often below freezing.

If warmer temperatures last longer into the fall and the average temperature in the winter is getting warmer, what do you expect to happen to the population?
The percentage of the population with brown fur will decrease.
The percentage of the population with white fur will decrease.
The population will increase in size, but the color percentages will remain unchanged.
The population will decrease in size, but the color percentages will remain unchanged.

Answer 1

1) Individuals that are well suited to the environment reproduce, and those that are not well suited die before they reproduce.
- Reason: When more offspring are produced than resources allow, natural selection favors traits that increase survival and reproduction.

2) Island finches did not have beaks of the same size and shape.
- Reason: Darwin noticed beak differences correlated with island diets, suggesting change over time.

3) competition among individuals for available food sources
- Reason: Different food availability on each island favored different beak shapes (adaptive divergence).

4) a possum playing dead to increase its chances of survival
- Reason: Playing dead is a behavior that increases survival—so it’s a behavioral adaptation.

5) The percentage of the population with white fur will decrease.
- Reason: Warmer winters reduce snow cover, so white fur (snow camouflage) becomes disadvantageous and browner individuals are favored.