Charles Darwin And Natural Selection


     Charles Darwin revolutionized biology when he introduced The

Origin of Species by Means of Natural Selection in 1859. Although Wallace had
also came upon this revelation shortly before Origins was published, Darwin had
long been in development of this theory. Wallace amicably relinquished the idea
to Darwin, allowing him to become the first pioneer of evolution. Darwin was not
driven to publish his finding, which heíd been collecting for several years
before Wallace struck upon it, because he had "never come across a single
[naturalist] who seemed to doubt to permanence of species" (Ridley, pp. 70).

What follows are the key points of Darwinís Theory of Natural Selection taken
directly from the two chapters concerning it in his book Origins. In chapter III
of Origins Darwin sets up his discussion on Natural Selection by establishing
the struggle for existence in nature. By this he means not only an individuals
need to fend of enemies and survive its environment but also itís ability to
create living, healthy, successful offspring. The first factor concerning this
struggle is the ratio of increase in any given species. Darwin explains how this
struggle must be occurring otherwise a single species would dominate the entire
earth because every single one of itís offspring would survive. This is due to
the fact that every species reproduces exponentially, a rate that would soon
produce astonishing numbers if left unchecked. This does not happen however,
because nature has a system of checks and balances. Although we may not be able
to detect these checks, we can see their effects by the indisputable fact that
one species doesnít completely dominate the planet. These checks consist of
enemies eating the young or even adults, the rigors of weather or environment,
and countless others. In this way birds, for example, cannot populate beyond
their food supply, and the grains they feed on are held in check, because even
though they may produce thousands of seeds only a few are able to reach
maturity. Darwin goes on to show how all plants and animals compete and relate
to each other in this struggle for existence. He does so by relating various
personal observations that show the introduction of a different species of plant
or animal can have a direct effect on the present survival of the indigenous
species and even allow other foreign species to proliferate. This leads to
interspecies survival, which Darwin considers the hardest struggle of all, and
the one that may have the greatest effect on the evolution of a species through

Natural Selection. It springs forth from the similarity in "habits and
constitution". Plants and animals of the same species must compete for the
same food and the same space to live in. Also, the original make-up of a plant
or animal may give it an advantage to thrive in an ever-competitive environment.

This brings us to Natural Selection and survival of the fittest that Darwin is
most known for. Darwin begins chapter IV by comparing human selection to
natureís ability to select, dubbing his theory Natural Selection, and
explaining how imperceptible it is for us (at least science in his time) to
examine the minute changes slowly taking place in nature. Variations in a
species now come into play, and how these adaptations concern Natural Selection.

Slight differences in an individual of a species will give rise to two
situations. One is that it will be an injurious variation, which will definitely
lead to the death of the individual because of the aforementioned struggle for
existence. The other is a favorable adaptation in the individual's ability to
gather nutrients, survive its enemies, survive its environment, etc. The chance
of this individual surviving is greater than its less adapted competitors,
however slight, which gives it a better chance of leaving progeny. These progeny
will also have these abilities, increasing their chances of survival. Changes in
the young can also bring about changes in the adult, as the individual
approaches maturity, due to the difference in its original constitution. Once
again, it will possibly leave new traits to itís progeny (if they are
advantageous and this variation doesnít die out), spreading the variation
throughout the community and continuing the cycle of evolution. This is also
known as ordinary selection because it begins with one individual and itís
constitution and habits. Another method of Natural Selection is sexual
selection. Sexual selection arises from interspecies cross breeding. This,

Darwin explains, deviates from the struggle for existence and becomes the
struggle for progeny. Advances in an individual will often allow it a better
chance to procreate. A males ability to woo the female by singing, shows of
strength, or decoration have definite effects as to whether or not he will be
able to mate. The same goes for the femaleís ability to attract the maleís
attention. Some of these techniques or differences can also sometimes be used in
the struggle for existence giving that particular variation the advantage.

Lastly, Darwin explains extinction and divergence of character in relation to

Natural Selection. With extinction Darwin shows it is necessary for the adapted
variation to proliferate. As the adapted variation begins to increase in numbers
because of its greater ability to survive conditions, it's obvious the older
variety must become rarer. Rarity is the first sign of extinction, because with
smaller numbers, there is a smaller chance of propagating, and a smaller chance
of adapting. This will eventually lead to complete extinction. Darwin places
much importance on the divergence of character within a species, also. It
explains how such a slight variation can lead to distinct species. It resides on
the basis that each of the variations is added generation upon generation. These
favorable adaptations when all put together make variations that are markedly
different from the original progenitor. All of this combines to form new,
distinct, better adapted life forms which have, since the beginning of life on
earth, been evolving into the diverse, lush, beautiful variety we experience
everyday. The Theory of Natural Selection Charles Darwin revolutionized biology
when he introduced The Origin of Species by Means of Natural Selection in 1859.

Although Wallace had also came up on this revelation shortly before Origins was
published, Darwin had long been in development of this theory. Wallace amicably
relinquished the idea to Darwin, allowing him to become the first pioneer of
evolution. Darwin was not driven to publish his finding, which heíd been
collecting for several years before Wallace struck upon it, because he had"never come across a single [naturalist] who seemed to doubt to permanence of
species" (Ridley, pp. 70). What follows are the key points of Darwinís

Theory of Natural Selection taken directly from the two chapters concerning it
in his book Origins. In chapter III of Origins Darwin sets up his discussion on

Natural Selection by establishing the struggle for existence in nature. By this
he means not only an individuals need to fend of enemies and survive its
environment but also itís ability to create living, healthy, successful
offspring. The first factor concerning this struggle is the ratio of increase in
any given species. Darwin explains how this struggle must be occurring otherwise
a single species would dominate the entire earth because every single one of
itís offspring would survive. This is due to the fact that every species
reproduces exponentially, a rate that would soon produce astonishing numbers if
left unchecked. This does not happen however, because nature has a system of
checks and balances. Although we may not be able to detect these checks, we can
see their effects by the indisputable fact that one species doesnít completely
dominate the planet. These checks consist of enemies eating the young or even
adults, the rigors of weather or environment, and countless others. In this way
birds, for example, cannot populate beyond their food supply, and the grains
they feed on are held in check, because even though they may produce thousands
of seeds only a few are able to reach maturity. Darwin goes on to show how all
plants and animals compete and relate to each other in this struggle for
existence. He does so by relating various personal observations that show the
introduction of a different species of plant or animal can have a direct effect
on the present survival of the indigenous species and even allow other foreign
species to proliferate. This leads to interspecies survival, which Darwin
considers the hardest struggle of all, and the one that may have the greatest
effect on the evolution of a species through Natural Selection. It springs forth
from the similarity in "habits and constitution". Plants and animals of the
same species must compete for the same food and the same space to live in. Also,
the original make-up of a plant or animal may give it an advantage to thrive in
an ever-competitive environment. This brings us to Natural Selection and
survival of the fittest that Darwin is most known for. Darwin begins chapter IV
by comparing human selection to natureís ability to select, dubbing his theory

Natural Selection, and explaining how imperceptible it is for us (at least
science in his time) to examine the minute changes slowly taking place in
nature. Variations in a species now come into play, and how these adaptations
concern Natural Selection. Slight differences in an individual of a species will
give rise to two situations. One is that it will be an injurious variation,
which will definitely lead to the death of the individual because of the
aforementioned struggle for existence. The other is a favorable adaptation in
the individual's ability to gather nutrients, survive its enemies, survive its
environment, etc. The chance of this individual surviving is greater than its
less adapted competitors, however slight, which gives it a better chance of
leaving progeny. These progeny will also have these abilities, increasing their
chances of survival. Changes in the young can also bring about changes in the
adult, as the individual approaches maturity, due to the difference in its
original constitution. Once again, it will possibly leave new traits to itís
progeny (if they are advantageous and this variation doesnít die out),
spreading the variation throughout the community and continuing the cycle of
evolution. This is also known as ordinary selection because it begins with one
individual and itís constitution and habits. Another method of Natural

Selection is sexual selection. Sexual selection arises from interspecies cross
breeding. This, Darwin explains, deviates from the struggle for existence and
becomes the struggle for progeny. Advances in an individual will often allow it
a better chance to procreate. A males ability to woo the female by singing,
shows of strength, or decoration have definite effects as to whether or not he
will be able to mate. The same goes for the femaleís ability to attract the
maleís attention. Some of these techniques or differences can also sometimes
be used in the struggle for existence giving that particular variation the
advantage. Lastly, Darwin explains extinction and divergence of character in
relation to Natural Selection. With extinction Darwin shows it is necessary for
the adapted variation to proliferate. As the adapted variation begins to
increase in numbers because of its greater ability to survive conditions, it's
obvious the older variety must become rarer. Rarity is the first sign of
extinction, because with smaller numbers, there is a smaller chance of
propagating, and a smaller chance of adapting. This will eventually lead to
complete extinction. Darwin places much importance on the divergence of
character within a species, also. It explains how such a slight variation can
lead to distinct species. It resides on the basis that each of the variations is
added generation upon generation. These favorable adaptations when all put
together make variations that are markedly different from the original
progenitor. All of this combines to form new, distinct, better adapted life
forms which have, since the beginning of life on earth, been evolving into the
diverse, lush, beautiful variety we experience everyday. Bibliography: Darwin,

Charles, The Origin of Species by Means of Natural Selection. New York, Random

House Inc, 1859. Ridley, Mark, The Darwin Reader. New York, W. W. Norton and Co,

1987.

Bibliography

Darwin, Charles, The Origin of Species by Means of Natural Selection. New York,

Random House Inc, 1859. Ridley, Mark, The Darwin Reader. New York, W. W. Norton
and Co, 1987.