Hugo de Vries gave the mutation theory to explain the mechanism of evolution. He conducted his experiments on ...... .

Which organisms are considered the most adapted in the environment?

The frequency of an allele in an isolated population may change due to

When we say 'survival of the fittest',does it mean that $(a)$ those which are fit only survive,or $(b)$ those that survive are called fit? Comment.

Mutation theory explaining organic evolution was proposed by Hugo de Vries. He worked on

$A$ scientist who worked on rats cut their tails up to $21$ successive generations,but at last,he found that the tails remained normal. Which scientist's theory is disapproved by this experiment?