froms of a common ancestral form. The driving force behind, it is adaptations to newly
involved habitat and the prevailing environmental conditions there. As the original
population increases in size, it spreads out from its centre of origin to exploit new habitas
and food resources.

In time this results in a number of populations each adapted to its particular habitat,
eventually these populations will differ from each other sufficiently to become new species.

A good example of this process is the evolution of the Australian marsupials into species
adapted as carnivores, herbivores, burrowers, fliers, etc, Another example is that of
peritadactyl limb in mammals.

The flipper of a seal, wing of a bat, forelimb of a male, front legs of horse and the arm of a
man perform different functions, but exhibit the same structural plan including same
pentadactyl pattern of bones.