The cause of aging in mammals,including humans,is:

Define and explain divergent evolution,convergent evolution,and mutation.

Normally,gametes are disease-free in human beings or even in other animals because:

In recent years,$DNA$ sequences (nucleotide sequence) of $mt-DNA$ and $Y$-chromosomes were considered for the study of human evolution,because

Scientists believe that evolution is gradual. However,extinction,which is a part of the evolutionary story,is often 'sudden' and 'abrupt' and also group-specific. Comment on whether a natural disaster can be the cause of the extinction of species.

The greatest evolutionary change enabling land vertebrates to be completely free from water was the development of