define variation in context of development of species - Science - Heredity and Evolution

Question

define variation in context of development of species

Mushtaq Ahmed · Accepted Answer

Variation is certain noticeable difference in characteristics
between the organisms of same group or species For e g; difference
in skin colour in humans, hair colour, eye colour, height etc
Variations accumulate to produce an organism more evolved than his
ancestors
Consider the following example:

A small population of beetles live in a bushy area with green
leaves Crows eat these beetles As a result, variation occurs in
these beetles due to sexual reproduction

Case I: Due to the occurrence of variation, the
colour of one progeny beetle changes from red to green
What is the advantage of this variation to green
beetles?
The green beetle can hide itself in leaves to escape from being
eaten by crows Thus, the variation provides a survival advantage to
the beetle
Hence, the red beetles are rendered more vulnerable Their
chances of survival to reproduce are lesser in comparison to green
beetles This leads to an increase in the population of green
beetles This type of variation, which increases the survival value
of an organism, is naturally selected and results in the formation
of new species

define variation in context of development of species.