Question

Read the sources given and answer any four from the questions given below:

Princeton University researchers B. Rosemary Grant and Peter Grant have been studying the evolution of Darwin's finches, for the last four decades, on the Galápagos Islands which are situated on the west coast of South American mainland. They have found that a new species of Darwin's finches developed in as little as two generations. This provides direct genetic evidence in which the new species arise. Their research has shown that the droughts on the island can drive evolutionary changes in the finches. Drought diminished the supplies of easily cracked nuts but permitted the survival of plants that produce larger, tougher nuts. Drought thus favoured birds with strong, wide beaks that can break these tougher seeds, This led to producing populations of birds with these traits. The Grants have estimated that if droughts occur about once every 10 years on the islands, a new species of finch would arise in only about 200 years.

1. According to the research study by Grants, appearance of new species points towards
   1. disuse of organs
   2. natural selection
   3. mutation selection
   4. artificial selection
2. The Grants study found that,the drought on Galapagos Islands led to
   1. depletion of easily cracked nuts
   2. depletion of large strong nuts
   3. finches migrating from main land
   4. reduced population on finches
3. During droughts in the island, survival of following types of plants was observed
   1. grasses with thin leaves
   2. plants with small nuts
   3. plants with tough nuts
   4. plants with small leaves
4. New species of Darwin's finches as observed by the research group were
   1. large and strong
   2. similar to main land
   3. had narrow, small beaks
   4. had strong, wide beaks
5. The study by Grants points towards the following evolutionary change
   1. droughts can occur on islands
   2. new species due to evolutionary changes
   3. scarcity of food on island
   4. migration of finches to main land

Answer 1

1. natural selection
2. depletion of easily cracked nuts
3. plants with tough nuts
4. had strong, wide beaks
5. new species due to evolutionary changes