Which evidence advocates the fact that monkey and man have common ancestry ?

 Ans. 1. Some organisms possess non-functional structures which in other organisms have essential functions. These structures called as vestigial organs. 

2. Man does not possess a tail like a monkey. 

3. However, he does have, a rudimentary tail-bone composed of four fused vertebrae in the same position. 

4. There are also some rudimentary muscles attached to the tail-bone. 

5. These muscles are like that of the muscles of the monkey which it uses to swing the tail. 

6. This evidence advocates the fact that monkey and man have common ancestry.