According to Hugo de Vries,speciation due to mutation is saltation,which means-

Which of the following phenomena supports Darwin's theory of natural selection in organic evolution?

The concept that "Population tends to increase geometrically while food supply increases arithmetically" was put forward by:

To be evolutionarily successful,a mutation must occur in the

In a population of plants,some were extremely tall,and the remaining were extremely dwarf. No plants of the population showed intermediate height. The type of operation of natural selection in the above case is

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.