Tag: natural selection

Questions Related to natural selection

The species which were not able to adapt to their environments through genetic changes to their skeletons were not able to survive. The given statement is an example of 

zoology variation examples of natural selection selection natural selection

  1. Skeletal Adaptations

  2. Coloration

  3. Physiological adaptations

  4. All of the above

Show answer
Correct Option: A
Explanation:

The given adaptation in lizard is an example of skeletal adaptation of natural selection. According to this adaptation, the individual who didn't develop the skeletal changes died. This type of adaptation can be seen in some species (lizards, giraffes) of animals who adapted themselves to the environment through genetic changes in their skeletons. For example, development of long neck in giraffes to reach food sources of the upper part of the trees. It is said that those died who didn't develop the long neck. Another example is development of longer leg bones in lizards to help them to climb up during periods of flood and to escape predators in the ground. Those lizards who didn't develop long leg bones, died. So, the correct option is A.

Which of the following has a natural selection as principle mechanism?

zoology variation examples of natural selection selection natural selection

  1. Adaptive radiation

  2. Convergent evolution

  3. Genetic variation

  4. None of the above

Show answer
Correct Option: A
Explanation:

Principle Mechanism:-

  • Variation. Organisms (within populations) exhibit individual variation in appearance and behavior.
  • Inheritance. Some traits are consistently passed on from parent to offspring.
  • High rate of population growth.
  • Differential survival and reproduction. 
  • Adaptive radiation:- A process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, creates new challenges, or opens new environmental niches.  So,the correct answer is "Adaptive radiation".

The animals having several adaptation and are able to adapt is given by theory of 

zoology variation examples of natural selection selection natural selection

  1. Evolution

  2. Natural selection

  3. Variation

  4. None of the above

Show answer
Correct Option: B
Explanation:

The Central idea of Darwinism is Natural Selection. He stated that nature selects the best-suited organisms that have a greater chance to become parents for the next generation who have adapted themselves. Thus, the correct answer is option B.

The peppered moths rested became blackened by soot, giving the dark-coloured moths

zoology variation examples of natural selection selection natural selection

  1. Advantage in hiding from predators

  2. Advantage in hiding from primary consumers

  3. Advantage in hiding from secondary consumers

  4. None of the above

Show answer
Correct Option: A
Explanation:

Due to changes in the environment, the dark coloured moths had a better survival chance as compared to the light coloured moths, which could be easily spotted. Hence, dark coloured moths got an advantage in hiding from predators. Hence dark coloured moths were able to leave the greater number of progeny. In other words, dark coloured moths were naturally selected and they were reproductively successful as compared to light coloured moths.

Thus, the correct answer is option A.

Peacock females pick their mate according to the males tail. The ones with the largest and brightest tails mate more often. The given example can be related to

zoology variation examples of natural selection selection natural selection

  1. Adaptive radiation

  2. Natural selection

  3. Convergent evolution

  4. None of the above

Show answer
Correct Option: B
Explanation:

The male peacock has a lot of showy feathers.However, peacocks use their feathers to attract peahens (female peacocks). The peacocks with the showier feathers are able to attract mates, so they are the ones that have offspring, and pass on the fancy-feather genes to the next generation.

So, the correct answer is  "Natural selection".

Read the passage and answer the following question.

A total of 12 bird species having distinct diets, behavior, coloration and beak shapes inhabit a large volcanic island in the South Atlantic 500 miles from the Coast of Africa not found on the mainland. Two species are flightless herbivores. A bird found on the mainland is related to these bird species but it does not fly over water but can occasionally survive at sea in a storm. There are no reptiles, mammals or amphibians on the island, although there are many insect and plant species.

The evolution of two flightless bird species on the island indicates

zoology variation examples of natural selection selection natural selection

  1. Flight improved the ability of the species to escape predators, but impaired food gathering on the ground.

  2. Flight originally evolved only to escape predators.

  3. Mimicry is a highly effective evolutionary strategy.

  4. The species had greater fitness without the ability to fly.

  5. Flight is not an effective means to escape predators.

Show answer
Correct Option: D
Explanation:

According to Charles Darwin, Natural selection is a tool of nature to impose the survival of the fittest. As some species fight to become the fittest, they adapt. Many organisms due to this, evolved, got adapted as they chose to survive in that habitat. Adaptation is the biggest drive to evolution and the pinpointed conclusion of the natural selection. 

So, the correct option is 'The species had greater fitness without the ability to fly'.

Read the passage and answer the following question.

A total of 12 bird species having distinct diets, behavior, coloration and beak shapes inhabit a large volcanic island in the South Atlantic 500 miles from the Coast of Africa not found on the mainland. Two species are flightless herbivores. A bird found on the mainland is related to these bird species but it does not fly over water but can occasionally survive at sea in a storm. There are no reptiles, mammals or amphibians on the island, although there are many insect and plant species.

Two of the bird species on the island are herbivores that both inhabit the same species of tree and eat the fruit the tree produces year-round. Which of the following helps both species to inhabit the tree without competing for resources?

zoology variation examples of natural selection selection natural selection

  1. One species lives in the top 30 percent of the tree and the other species lives in the lower 70 percent.

  2. One species is nocturnal and the other is active during the day.

  3. Reproductive isolation exists.

  4. The species have differing beak shapes.

  5. One species must become extinct.

Show answer
Correct Option: A
Explanation:

This phenomenon is called Resource partitioning. When the resources in a niche are limited, so as to avoid the competition species divide the resources accordingly.

According to R* rule of limited resources of ecology, If two species are living in a resource limiting space, the species which can survive in the lowest equilibrium of resource will only resist the extinction. Coexistence is only possible if each species have the low R* on that resource.
So, the answer is 'One species lives in the top 30 percent of the tree and the other species lives in the lower 70 percent'.

Replacement of the lighter-coloured variety of peppered moth (Biston betularia) to its darker variety (Biston carbonaria) in England is the example of

zoology variation examples of natural selection selection natural selection

  1. Natural selection

  2. Regeneration

  3. Genetic isolation

  4. Temporal isolation

Show answer
Correct Option: A
Explanation:
In England, before industrialisation in $1860$, it was observed that there were more white-winged moths on tree trunks than dark-winged or melanised moths. But after industrialisation in $1920$, there were more dark-winged moths in the same area. Before industrialisation, the tree trunks were covered by white-coloured lichens. In that background, the white-winged moths survived but the dark-winged moths were eaten by predators. During post industrialisation period, the tree trunks became dark due to industrial smoke and soot. Therefore, the white winged moths could not survive due to predators but dark-winged moths survived, i.e., the moths that were hidden in background survived. Thus, industrial melanism supports evolution by natural selection.

So, the correct answer is 'Natural selection'.


The adaptation shown by the bacterium Pseudomonas for metabolization of nylon is an example of

zoology variation examples of natural selection selection natural selection

  1. Genetic variation

  2. Natural selection

  3. Neo-Lamarckism

  4. None of the above

Show answer
Correct Option: B
Explanation:

Pseudomonas is the genus of a bacterium. This bacterium was placed in the medium where only nylon was present. This resulted in the development of the bacterial species which was able to metabolize the nylon. The nylon was the only source of food available so, the organism adapted itself to feed on the nylon. This is an example of natural selection.

Thus, the correct answer is option B. 

Read the following statements and select the correct option.
(i) Increase in melanised moths after industrialisation in Great Britain is a proof for natural selection.
(ii) When more individuals of a population acquire a mean character value, it is called disruption
(iii) Changes in allelic frequency in a population will lead to Hardy-Weinberg equilibrium.
(iv) Genetic drift changes the existing gene or allelic frequency in future generations.

zoology variation examples of natural selection selection natural selection

  1. Only (ii) is correct

  2. Only (iv) is correct

  3. Both (i) and (iv) are correct

  4. Both (i) and (iii) are correct

Show answer
Correct Option: C
Explanation:

When more individuals of a population acquire a mean character value, it is called stabilising selection. No change in allelic frequency in a population will lead to Hardy-Weinberg equilibrium.

So, the correct option is 'Option C'.