Natural selection
Natural selection is the differential survival and reproduction in some individuals
over others due to the possession of certain genotypic and phenotypic traits. It is
responsible for the evolution of new species with more advanced traits.
The characteristics of the theory of natural selection are:
• Variation: Random mutations that occur in the genome of an organism due
to interaction with its environment are responsible for the variations.
Individual variation in an organism's appearance and behavior can be seen in
populations of organisms. The variances that confer adaptive morphological,
physiological, or behavioral characteristics to survive in an environment are
favored by natural selection.
• Inheritance: The mechanism by which certain characteristics are passed on
from parents to children is referred to as heredity and the passing on of
genetic material from parents or ancestors to offspring or descendants is
called inheritance. The qualities of the "fittest" phenotypes that survive
must be passed down to the successful descendants for natural selection to
occur and for evolution to proceed. Individuals that are capable of
transmitting their traits to their progeny are favored in natural selection.
• High rate of population growth and competition: Competition is an
interaction between organisms where the presence of one organism
reduces the fitness of another. This could be a result of the fact that both
depend on a finite amount of a resource like food, water, or land.
Competition may occur inside a species or between species, and it may also
be covert. Since competition plays a significant part in natural selection,
species that are less adapted to compete should, in theory, either adapt or
become extinct. According to Darwin's theory of natural selection, a
population needs competition to evolve. Natural selection will not take place
if every member of a population has the same chance of surviving. Any
offspring with favorable traits is more likely to survive and have more
offspring than those with less-favorable traits. The fittest offspring in terms
of their adaptation to the environment will survive and reproduce.
• John Ray and Carolus Linnaeus were both 18th-century naturalists who made
significant contributions to the field of taxonomy, the classification, and
naming of living organisms.
