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Farid Gazizov Impact of Evolution on Human Thought Evolution


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Farid Gazizov

Impact of Evolution on Human Thought

Evolution

Evolution by definition of Webster dictionary is a gradual development
of simple matters into more complex. When most of the people hear
“evolution” it associates with development or history of the earth.
History of the earth compiles of gazillions of steps. The very first
step in our history is a birth of the earth, which took place over 4
billion years ago.

“Powerful telescopes reveal new stars coalescing from galactic dust,
just as our sun did more than 4.5 billion years ago. The earth itself
formed shortly thereafter, when rock, dust, and gas circling the sun
condensed into the planets of our solar system. Fossils of primitive
microorganisms show that life had emerged on earth by about 3.8 billion
years ago (Teaching about evolution and the Natural of Science, ch. 1).”

Many people throughout the centuries have been trying to find
explanations to the questions like: Why are surrounding us things the
way they are?; why some type of animals resemble another one? It was
hard to answer these questions without proper tools, experience and
background knowledge. Even nowadays, not all questions are answered.
Darwin was the first human who succeeded in responding to these
questions. He was the first one who put discovered facts and knowledge
available by his time in one big picture. In attempts to explain the
history Darwin created the most outstanding achievement of human beings
that had enormous impact of our thinking—evolutionary thinking. Ernest
Mayer, in his book “One Long Argument” says following about impact of
Darwin’s work on human thinking.

“It is almost impossible for a modern person to project back to the
early half of the nineteenth century and reconstruct the thinking of
this pre-Darwinian period, so great has been the impact of Darwinism on
our views (E. Mayr, pp. 1)

For our further discussion, one should explicitly distinguish between
evolution and evolutionary theory. Evolution (history) is a serious of
facts that occurred since the birth of the earth, while evolutionary
theory is the best way available nowadays to explain why evolution
happened the way it happened, but not otherwise. Both evolution and
evolutionary theory make series of claims. Some of them are secondary
and some are primary. Primary claims if proved wrong, would change
entire theory.

Primary Claims of Evolution

The earth is over 4 billion years old. In the past when technology was
not very developed it was hard to prove age of the earth. Scientists
had been aging by measuring the rate of sedimentation. Another method
of defining age, which was used in 1800s, is noticing what kinds of
fossil rocks have. Currently it is done by chemical analysis of
composition of fossil.

“Some elements such as uranium, undergo radioactive decay to produce to
produce other elements. By measuring the quantities of radioactive
elements and elements into which they decay in rocks, geologists can
determine how much time has elapsed since the rock cooled from initially

determine how much time has elapsed since the rock cooled from initially
molten state (Teaching About Evolution and the Nature of Science).”

Life on the earth did not appear right after appearance of the earth.
The first sings of life were dated about 550 million years ago according
to the oldest fossils. This fact does not specifically mean that where
was not life forms before that time. Life forms were very simple and
lacked hard parts like bones or shells and could rarely preserve in the
fossils.



“However, a few pre-Cambrian organisms left traces of their existence.
Some ancient rocks contain stromatolities—the remnants of bacteria that
grew in columns like stacked pancakes (Teaching About Evolution, ch. 3,
pp. 2)

Extinction is a major feature of biological evolution. It is in a tight
connection with natural selection. Natural selection works only by
means of surviving of changes, in some sense useful, and therefore,
striking root. In the consequence, fast increase of the numbers of all
organic matters in geometrical progression, every natural habitat
already filed to the limits by its habitants. From this it follows
those more adapted forms will increase in numbers and less adapted, will
decrease in numbers and become rare. Rarity of the form is a
predecessor of the extinction. Every form represented by small numbers
of individuals has big chances for a complete extinction in consequence
of significant climatic swings within a year or in consequence of
temporary increase of enemies. Species, most abundant of individuals,
have the biggest chances for appearance at any particular time of
favorable changes. Rare individuals will at any particular time change
and perfect at a slower pace and in consequence of that will be defeated
in a life struggle with changed and improved descendants of more common
individuals. From this it follows that since with a passage of time
natural selection “creates” new species, than other species become more
rare, and finally extinct.

For example, during laying eggs season, sea turtles hay hundreds of
thousands eggs. While hatching and getting to the ocean most of the
generation becomes easy pray of sea birds. Since just hatched turtles
do not have a hard cover that could protect them, many of them dye in
the ocean. By maturity time only about one out of thousand turtles stay
alive. Currently there are billions of living organisms that inhabit
the earth, but they represent only around one percent of all living
organisms that have ever lived on the earth since its birth. Ninety
nine percent dyed out.

Another example that mechanisms of evolutionary change are observable
and verifiable is the one described by Henry Walter Bates.



“In 1862, Henry Walter Bates made brilliant use of the Darwinian
mechanism of natural selection asking why it is that some species of
butterfly very closely mimic species of butterfly, essentially quite
different, Bates proved beyond doubt that the answer lies in adaptive

r lies in adaptive
advantage brought about by natural selection. The mimicked insects are
highly distasteful to birds who think that they belong to distasteful
species. Bates showed experimentally that birds learn to avoid
distasteful insects, and that the closer the mimic, the less change
there is that the insect will be eaten.”

Secondary Claims of Evolution

When the earth appeared for the first time it was very different from
its current conditions. The surface of the earth was represented by
bare bedrock. At the time of its birth, the earth represented cold
matter, close by its composition to meteorites. Material it was mad of,
contained radioactive elements. In consequence of the heat excretion
while radioactive decomposition of the core and gravitational
compression. However, because of continuous loss of heat through he
surface and lack of radiation heat complete melting of the earth did not
happen. In result of earth’s melting, water and different gases were
brought up to the surface. This water began formation of hydrosphere.

Location of continents and oceans were very different. According to
Wegener’s hypothesize, which he later supported by evidence, earth’s
continents used to be a single land, which was called Pangea. About
two hundred million years ago Africa and South America slowly began
their movement toward their current location. Wegener supported his
hypothesize by geological and biological evidence. At the place where
the continents were aligned, were found fossilized animals and plants
dated more than two hundred million years old. Besides, if Africa and
South America had always been separate continents as they are now, both
of them would have had very different flora and fauna, which are not.

Starting at 1950 up to 1970 evidence begin exposing to the world that
support hypothesis of continent’s slow movement. Sonar mapping of the
ocean floor showed winding, continuous ridges system around the planet.
The ridges appeared where molten matter was coming up from the earth’s
inside.



Not only topography of the earth has changed, but composition atmosphere
has changed as well. Current atmosphere contains a lot of oxygen,
which is result of existence of life. During photosynthesis, green
plants consume water and dioxide and release oxygen in atmosphere. This
is considered to be a secondary claim because even if the earth would
not developed as it considered, it would have no impact on evolutionary
theory.

Origin of human being was an interest of human more than origin of plant
and animals. Attempt to understand and explain origin of humans is
expressed in religions, legends of all kind of trails and folks. For a
long period of time science knowledge were abrupt and incomplete in
order to solve a problem of human origin. Only in 1857 Darwin expressed
hypothesis, and in 1871 in his book “The Origin of man and relation to
sex,” convincelly proved that humans originate from pre-existing
humanlike, but were not created by intelligent designer. Role of social

t were not created by intelligent designer. Role of social
factors, which was pointed out by Darwin, was detailly described by
Fredrik Engels in his book “Role of labor in the process of turning ape
into humans.” (1896)

Human and vertebrates commonness is strongly supported by similar
arrangement of internal organs: skeleton, nerve system, blood system,
respiration, and digestion.

Rudiments and atavisms are very important evidences of human relatedness
to animals. There are about 90 rudiments in human body: coccyx bone
(remaining of the reduced tail); folds in the corner of the eyes
(remaining of the blinking tympanum; thin body hair (remaining of the
hair). All these rudiments are inherited from an animal ancestor. An
external tail, which sometimes people are born with, is related to
atavisms. Another atavism is abandon hair on the face and body.

Common details of the body arrangement are evidence of close
relativeness of human and anthropoids: wrist with flat nails, shape of
eyes and years, the same number of canine and molar teeth, complete
change of baby teeth, and so forth. Physiological commonness is very
important: the same blood groups, diseases (tuberculosis, fly,
smallpox, cholera, AIDS, pneumonia) and parasites (louse). Besides
numerous common features, there is a number of explicit differences
evidencing that its current stage, human is considered to be different
species. Only human has ability of upright walking and related to that
peculiarity of structure of the S-shaped backbone with explicit neck and
lumber bend, low extended pelvis, and etc. Human skull is higher and
more rounded without superciliary arch; brain part of skull is in most
part dominated by facial; high forehead, weak jaws with small canine.
Human brain is about two and half times bigger than one of humanlike
apes, and 3-4 times heavier.

Human being evolved from other pre-existing species. Even in ancient
times it has been noticed that humans have a lot of in common with a
other animals just like other animals human had the same internal organs
(heart, lungs, liver etc.). Ancient Greeks had a scale of living
organisms known by their time. Human being was placed at the end of the
scale. Below were higher animals like houses, sheep and so forth, but it
is hard to believe that humans were next step in the biological
evolution of living organisms right after higher animals. Only by the
eighteenth century ape-like being became known to Europe. This discover
shed light on a huge gap between higher animal and humans (Darwinism
defended, Ruse, pp. 230). After that some scientists (for example
Huxley) assumed that humans descended from apes. Later, having examined
all differences between apes and humans, Huxley came to conclusion that
humans and apes descended from a common ancestor. One would probably
ask why our common ancestor did split into two branches, apes and
Australopithecus afarensis (which is considered to be an ancestor of all
hominids). There is a scientific explanation, which relates to climatic

. There is a scientific explanation, which relates to climatic
changes in Africa. Our ancestor was used to live in the area of heavy
precipitation. With a passage of time climate started turning into dry
one and forestlands began retreating, leaving behind Savannah’s. Some
species stayed in dwindling forests. Others (our ancestors) started
advancing toward opened spaces.

With a change of place of inhabitation, there were some changes in diet
of our ancestor. Anthropologists suggested that tooth reduction took
place because our ancestor started to use grass seeds and the like as a
food source (Darwinism Defended).

Major Claims of Evolutionary Theory

Natural selection is the major moving factor of the evolution of the
living organisms. Almost at the same time, several English naturalists
arrived at the idea of existence of natural selection (P. Mathew (1831),
A. Blight (1935), A. Wallace (1858), C. Darwin (1858)), but only Darwin
succeeded in exposing of the meaning of this phenomenon as the major
factor of evolution and created the theory of natural selection. On the
contrary, to artificial selection held by humans, natural selection is
conditioned by influence of surrounding environment upon the organisms.
According to Darwin natural selection is survival of the most
accommodated organisms, in consequence of which, on the basis of
undefined inherited changeableness in the series of generations
evolution occurs.

In process of natural selection species more accommodated to surrounding
environment survive, those who do are not, go extinct. Explicit example
of that is our ancestors that had advantage of standing upright to look
out and look for possible object of prey. Natural selection does not
specifically have to lead to perfection. It leads only to surviving of
species that can survive. If entire kind of particular animals can not
survive in changed environment, entire kind will dye out.

“Organisms in nature topically produce more offspring that can survive
and reproduce given the constraints of food, space, and other resources
in the environment. These offspring often differ from one another in
ways that are heritable—that is, they can pass on the differences
genetically to their own offspring. If competing offspring have traits
that are advantageous in a given environment, they will survive and pass
on those traits. As differences continue to accumulate over
generations, populations of organisms diverge from their ancestors.”

Process of natural selection consists of two steps: the first one is
reproduction of genetically different species; the second step is
surviving of the most adopted individuals in surrounding environment. An
example can be nest of birds in which some nestlings have a little bit
different coloring than others. If this coloring better matches the
tree these birds in habit, this will give them advantage of better
hiding from predators, which leads to increase in changes of
reproduction. Below are example that Wallace, Alfred Russle uses in his

re example that Wallace, Alfred Russle uses in his
book “Contributions to the theory of Natural Selection” to demonstrate
natural selection.

“The Duke of Argyll, in his “Reigh of Law,” has pointed out the
admirable adaptation of the colors of the woodcock to its protection.
The various browns and yellows and pale ash-color that occur in fallen
leaves are all reproduced in its plumage, so that when according to its
habit it rests upon the ground under trees, it is almost impossible to
detect it. In snipes the colors are modified so as to be equally in
harmony with the prevalent forms and colors of marshy vegetation. Mr.
J.M.Lester, in a paper read before the Rugby School Natural History
Society, observes: --“The wood-dove, when perched amongst the branches
of its favorite fir, is scarcely discernible; whereas, were it among
some lighter foliage, the blue and purple tints in its plumage would far
sooner betray it. The robin redbreast too, although it might be thought
that on its breast made it much easier to be seen, is in reality not at
all endangered by it, since it generally contributes to get among some
russet or yellow fading leaves, where the red matches very well with the
autumn tints, and the brown of the rest of the body with the bare
branches.”

Core of natural selection is variation within the kind. If variation
does not exist either entire kind will survive and stay unchanged or it
will go extinct. But what it a source of variation? The ultimate source
of variation is mutations in genes. If new traits gained through
mutation leads to successful survival and reproduction than new traits
will be inherited and spread within the population. Mutation is random,
but natural selection is not.

All living organisms that currently inhabit the earth share common
ancestry. Through the history by means of natural selection and
variation first, simple forms of life were evolving into different, more
complex forms. How to prove it?



“The discovery of the structure of DNA by Francis Crick and James Watson
in 1953 extended the study of evolution to most fundamental level the
sequence of the chemical basis in DNA both specifies the order of amino
acids in proteins and determines which proteins are source of both
change and continuity in evolution. The modification of DNA through
occasional changes or rearrangements in the base sequences underlies the
emergence of new traits, and thus of new species, in evolution. At the
same time, all organisms use the same molecular codes to translate DNA
base sequences into Protein amino acid sequences. This uniformity in
genetic code is power evidence for the interrelatedness of living
things.” (Teaching About Evolution and the Nature of Science, ch. 2, pp.
4)

Another powerful argument that supports common ancestry is a fact that
man is developed from an ovule, about the 125th of an inch in diameter,
which does not differ from the ovules of other animals. At a very early
period, the embryo can hardly be distinguished from another member of

can hardly be distinguished from another member of
vertebrate kind.

In order to convince one that evolution happened the way evolutionary
theory describes it evidences must be presented. Major evidence and
argument of evolutionary theory is that all of the mechanisms of
evolutionary theory change are currently observable. Let us take for
example main mechanism of evolutionary change—natural selection.
Nowadays our society is facing serious public health problem. Bacteria
that medicine used to successfully fight with antibiotics is becoming
more resistant to one. This means that week bacteria go extinct and
only strong (more resistant to antibiotics) bacteria survived. (Teaching
about evolution, ch. 2, pp. 5) “continued use and overuse of
antibiotics has had the effect of selecting for resistant population
because the antibiotics give these strains and advantage over
non-resistant strains”

Bibliography

“Long Argument,” Ernest Mayr, Harvard University Press, 1991.

“Darwinism defended,” Michael Ruse, Addison-Wesley Publishing Company,
1982.

“The Descent of Man and Selection in Relation to Sex,” Charles Darwin,
1974.

“Wonderful Life,” Stephen Jay Gould, W.W. Norton & Company, 1989.

“Contributions to the theory of natural selection,” Wallace, Alfred
Russel, AMS Press, 1973.

Teaching about Evolution

A. afarensis

A. africanus

H. habilis

A. robustus

H. erectus

H. sapiens


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