Question

Which of the following changes for man in the course of evolution is probably useless?
          (A) Loss of tail.
          (B) Development of opposable thumb.
          (C) Development of being erect.
          (D) Development of cranial capacity.

Answer 1

Hint:
evolution is the change in the characteristics of a species over several generations. It is based on the process of natural selection.

Complete step by step answer:
Humans don’t have a tail now after evolution and this happened not once but two times. After evolution, when humans evolved from four to two legged, the tail created problems instead of help. Though it wasn’t that much useful earlier either. And each body part needs energy to grow so the energy which would have been used upon the tail is useless completely.
Tails are an almost standard issue in the animal kingdom. Fishes use them as propulsion., lizards use them as decoys, for crocodiles it is as fat reserves.
Moreover, tail plays an important role for animals as it helps them to maintain balance. But, when it comes to humans it doesn’t help in balance as humans have two legs and hands for maintaining balance.
Apart from this, the development of erectness is very useful as compared to tail and it is due to the major changes in the muscle skeletal system. The size of skull and volume of cranial cavity increased in order to accommodate the complex and large brain.
The evolution of the fully opposable thumb is usually associated with Homo habilis. This is the evolution from homo erectus.
Hence, the correct answer is option (A). Loss of tail.

Note:
‘Charles Darwin’ is known as the father of Evolution. He was born in 1809 and became a naturalist, biologist and geologist who widely contributed to the science of evolution.