Question

How many of the following develops as a result of divergent evolution i.e. the same structure developed along with different directions due to adaptation to different needs?

(a) Sweet potato and potato
(b) Thorn of Bougainvillea and tendril of Cucurbita
(c) Flippers of penguin and dolphin
(d) Wings of bat and flippers of the whale
(e) Eyes of octopus and mammals
(f) The sting of honey bee and scorpion

• A. Two
• B. Three
• C. Four
• D. Five

Answer 1

Answer: (B)

Three

(a) Sweet potato is a root modification and potato tuber is a stem modification but they show convergent evolution because both of them are unrelated and perform the functions similar to the storage of food and vegetative reproduction.

(b) The thorns of Bougainvillea and tendrils of Cucurbita are homologous organs- Divergent evolution.

(c) Dolphins evolved from mammals that walked on land, whereas, penguins evolved from birds that flew in the air. Both organisms developed similar structures (i.e. flippers because they both can swim in the water). This is an example of convergent evolution.

(d) Bat wings consist of flaps of skin stretched between the bones of the fingers and arm. Birds wings consist of feathers extending all along the arm. They don't have a common ancestor. So it is convergent evolution.

(e) Eyes of octopus and mammals show analogy that is structurally different but functionally the same. So they are an example of convergent evolution.

(f) The sting of honey bee and scorpion are homologous organs and so they show divergent evolution.

So, the correct answer is '2'.