Download Evolution - Nikhil Madhav

Evolution
By Nikhil Madhav, Sophia Kirkland, and Clayton Wilks
Evolution
 Evolution, originally labeled as descent with modification, is a process by
which a species adapts to its current environment. Through the selection of
“fit” genes to pass onto offspring, organisms become more specifically
adapted to their environment.
 While the environment that a species lives within can handle a certain
number of individuals within a population, it cannot sustains every
individual. This is reason for the selection of “fit” individuals. Those that can
survive to adulthood usually pass on their genes to the offspring, continuing
the process. Those who are “unfit” to survive in their environment rarely, if
ever, pass on their genes to the next generation.
Populations
 Each population in a species has its own genetic variation within itself,
giving rise to different physical appearances or attributes. Those within the
population that have more useful characteristics usually continue to
reproduce. These individuals pass on these genes to their offspring,
continuing their genes for an extended period of time. This progression of
“fit genes” leads to a stronger population.
Gene Flow and Mutations
 As populations move, they can, and do, breed with other individuals of the
same species. This gene flow can increase variations within a species, such
as colors in the population skin or variation within morphology
 Another mechanism by which evolution can occur is through mutations. A
mutation is a change within the genetic makeup of an individual. While a
mutation can be detrimental to an individual, it can be a neutral or even a
positive attribute. This can give rise to new populations
Sexual Selection and Allopatric Patterns
 Sexual selection can also have a part in the evolution of populations.
Individuals in a population, either male or female, can choose to mate with
individuals that they see fit, while those who the individuals they see
“unattractive” may not reproduce at all. Although these individuals may
reproduce, they may not be the most fit to live.
 Populations can change due to other changes in the environment. When
change in the environment occurs, an allopatric pattern occurs. This occurs
when a population is separated, forcing the breeding of individuals which
gives rise to new populations. Individuals with different genes breed with
others in the same area, while the population in another area breeds with
others of that same area.
Evolution
 Evolution is a mechanism with which new lifeforms occur from others. This
process is observed as taking an extended period of time, usually thought
as being several million years. Although this time is unobservable due to
human lifespan, we can see current species and how they may relate to
other individuals.
Critiques
 While many believe that the theory of evolution ties much of science
together, the theory has many shortcoming and errors that could
potentially disprove the theory.
Critique #1-The Miller-Urey Experiment
 Many theorists believe that life arose about 3 to 4 billion years ago due to
chemical reactions. The production of a primordial soup would have been
one of the first parts of the origin of life. In 1953, an experiment was made to
try and produce these chemical building blocks in conditions similar to
Earth’s early atmosphere, mostly reducing gasses (Bontemps, 2014).
Critique #1-The Miller-Urey Experiment
 However, it is now believed by geochemists that the early atmosphere of
earth did not contain as many of these gasses as we originally thought they
did, meaning that there is no evidence that a primordial soup ever existed
(Rana, 2007).
 Earth’s early atmosphere was thought to have been produced by
outgassing from volcanoes, whose gasses are related similarly to Earth’s
inner mantle. Studies have found that the properties of Earth’s mantle
would have been the same as they are today but volcanic gasses are not
currently reducing (Luskin, 2012).
Critique #2-Dehydration Synthesis
 In order to form polymers, dehydration synthesis is required (Luskin). If Earth’s
atmosphere was like a primordial soup, then it would have been vastly
water-based (Luskin, 2012). In this vastly water-based environment, many
monomers cannot join together to form polymers (Shanti and Saraswat).
Instead, larger molecules would have broken down into monomers.
Critique #3-The Cambrian Explosion
 The Cambrian explosion was when hundreds of animals suddenly
appeared in the evolutionary scene around 530 million years ago (Miller 2).
There is evidence that supports this from the Cambrian layer of the
geologic column.
Critique #3-The Cambrian Explosion
 However, many scientists have now begun to believe that it is impossible for
so many species to have evolved in such a short amount of time (Robert).
 The proof that is available for this theory is that the layers below the
Cambrian layer have virtually no fossils (“Cambrian”).
 So supposedly, only God could have caused all of those animals to have
evolved so quickly.
Critique #4-The Fossil Record
 Charles Darwin had a theory that the fossil discoveries would confirm his
theory of evolution. His theory was that countless transitional forms must
have existed, and that they would adapt from one step to the next,
eventually evolving into a highly evolved being (“Darwin’s).
Critique #4-The Fossil Record
 Scientists have not been able to discover that there are no transitional
fossils of any species (Wallace).
 If transitional fossils do indeed exist, then the gaps between adaptations
are far too large to use as evidence (Foard, 1996).
Critique #5-RNA World
 Scientists have believed that one of the most crucial pieces to the origin of
life is that more and more complicated molecules began to self-replicate
(Luskin, 2012). They believed that this happened by chance. One of these
molecules that was thought to have developed was RNA. The RNA world
hypothesis states that some of the first organisms used RNA to fill the
functions done by DNA and proteins (Jain 2).
Critique #5-RNA World
 However, this hypothesis has many flaws. If RNA had existed at the time of
the first organisms, then it would have had to arise by unguided, nonbiological chemical processes (Bernhardt, 2012). RNA cannot assemble
without the help of a skilled laboratory chemist guiding the process.
 Chemist Robert Shapiro shared his thoughts on this hypothesis by saying,
“The flaw is in the logic-that this experimental control by researchers in a
modern laboratory could have been available on the early Earth.”
Our Consensus
 Before this project, we were all for evolution and we didn’t doubt the
theory or have any significant questions or concerns about it.
 After we all did our separate research in regards to the project, our
viewpoints began to change a bit.
Our Individual Views
 After the project research, we each reached our own viewpoints.
 Sophia was still for evolution because she believed it was able to tie many
parts of science together.
 Clayton did not support evolution but at the same time was not completely
against it. He believed that organisms are able to adapt but could not
evolve into completely new species.
 Nikhil had a similar viewpoint of Clayton’s. He also believed in certain parts
of evolution but did not believe in others.
Our Decision
 We had a discussion together to try and reach a decision on how we all
stand as a group on evolution. Clayton and Nikhil shared similar viewpoints
while Sophia was for evolution.
 Each person shared their thoughts and views on the matter during the
discussion. Once everyone did this, we all shared our final thoughts. Nikhil
and Clayton’s views did not change while Sophia’s view changed. Other
than organisms being able to adapt, Sophia did not feel as strongly as
evolution as she did before.
 At the end of this project, none of the group members felt strongly about
evolution and all of the group members were able to learn about
important facts and pieces of evidence over why evolution could be false.
Citations

Bontemps, Johnny. “New Study Revisits Miller-Urey Experiment at the Quantum Level.” Astrobiology Magazine. 9
September 2014. Web. 9 February 2015.

Luskin, Casey. “Top Five Problems with Current Origin-of-Life Theories.” N.p. 12 December 2012. Web. 19 February
2015.

Rana, Fazale. “Biology Textbooks Get It Wrong on Life’s Origin.” Reasons to Believe. 2 August 2007. Web. 21
February 2015.

Luskin, Casey. “Top Five Problems with Current Origin-of-Life Theories.” N.p. 12 December 2012. Web. 19 February
2015.

Luskin, Casey. “Problems with the Natural Chemical Origin of Life.” Idea. N.d. Web. 21 February 2015.

Shanta, Bhakti, and Sri Saraswat. “Chemistry Never Made The Transition To Biology.” Science and Scientist. N.d.
Web. 21 February 2015.

Miller, Keith. “The Fossil Record of the Cambrian Explosion: Resolving the Tree of Life.” N.p. June 2014. Web. 19
February 2015.

N.a. “Cambrian Explosion Disproves Evolution.” Learn the Bible. N.d. Web. 19 February 2015.

Carroll, Robert. “Cambrian Explosion.” The Skeptic’s Dictionary. N.d. Web. 20 February 2015.
Citations

N.a. “Darwin’s Failed Predictions.” Judging PBS. N.d. Web. 20 February 2015.

Wallace, T. “Five Major Evolutionist Misconceptions about Evolution.” The True Origin. N.d. Web. 20 February 2015.

Foard, James. “Fossils: History Written in Stone.” The Darwin Papers. 1996. Web. 20 February 2015.

Luskin, Casey. “Top Five Problems with Current Origin-of-Life Theories.” N.p. 12 December 2012. Web. 19 February
2015.

Berhardt, Harold. “The RNA world hypothesis: the worst theory of the early evolution of life.” NCBI. 23 July 2012.
Web. 20 February 2015.

Jain, Mahesh. “Origin of Life: What is Wrong with RNA World Hypothesis.” N.p. 14 January 2014. Web. 20 February
2015.

N.a. “Tracking SARS back to its source.” Berkely. July 2013. Web. 20 February 2014.

N.a. “What Is Mutation.” Learn Genetics. N.d. Web. 20 February 2015.

Reece Jane B., Urry Lisa A, etc. Campbell Biology Ninth Edition, Chapter 24, Pg. 15-16