Evidence for Evolution
Webquest
Proof of evolution from fossil records, anatomical
evidence, embryology, and biochemistry
Yrbenka Arthus
Period 2
March 29th, 2010
Fossil Evidence
“The proof is in the pudding.”
Well in this case, the proof is in the fossils. Fossils are remains of organisms (animals and plants) that
lived long ago. There are five main types of fossils: trace fossils, casts, molds, petrified fossils, and amberpreserved fossils. Each type of fossil has its own way of telling paleontologists a story of an organism of very
long ago. A paleontologist is a scientist that studies ancient life, especially fossils. They use these remains in
order to discover the kinds of organisms that lived long ago, and are sometimes able to depict that organism’s
behavior. Fossils are most normally found under layers of rocks. Lower layers, those further down, are the
oldest—the newer layers are found on top. Over time, nature erodes soil and layers build on top of each other,
burying fossils deep underground. Though hard to come by, fossils are very good clues to finding out life’s
history. “Fossils can tell us about growth patterns in ancient animals.” Through fossils, paleontologists are able
to determine and understand life forms of long ago. Through stories like Jurassic Park and children’s’ cartoons
like Land Before Time, kids are able to learn about dinosaur—unimaginable creatures of millions of years ago.
Using the fossil record, scientists learn that “there has been a tremendous variety of living things.” The evidence
shows that life forms of long ago differentiate extremely from the species of today. Besides the prehistoric
aspect of them, fossils are nothing new. Until this day, fossils have been turning up everywhere. Entire
organism-outlines of fossils have been found; others remain jigsaw puzzles. Oftentimes, there appears to be
“gaps in the fossil record are due to incomplete data collection.” These so-called “missing links in the chain of
evolution” make piecing together entire structures of fossils difficult. The most common organisms that fossils
are found of are dinosaurs (reptiles of the past) and plants that existed long ago. By piecing together ancient
organisms, paleontologists have come to find fossils as evidence that species have changed over time. Handled
very carefully, fossils are an essential tool in the study of evolution and life throughout Earth’s history. Because
it comes to many people’s interest, fossils not being studied by archeologists are able to be admired by the
public in museums. “It [fossil evidence] shows that the earliest organisms were simple living things. They lived
in water. Fossils show that these organisms evolved into more complex organisms over millions of years.”
"Examining the Fossil Record." The Biology Corner. N.p., n.d.
Web. 21 Mar. 2010.
<http://www.biologycorner.com/worksheets/fossilrecord.html>
.
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2010. <http://bioweb.cs.earlham.edu/912/evolution/HTML/live.html>.
"Early Theories of Evolution." Evolution. N.p., 12 Mar. 2010.
Web. 30 Mar. 2010.
<http://anthro.palomar.edu/evolve/evolve_3.htm>.
Anatomical Evidence
“Evolutionary ER”
Anatomy, an interesting study, can be used in many ways. Doctors use it to observe patients; television
uses it to disgust and entertain, and scientists use it as evidence of evolution. Anatomy is the study of the parts
of living things. Evolutionary biologists view similarities in structure as evidence that organisms evolved from a
common ancestor. These structures many be similar in arrangement function, or both.This does not. Scientist
study different body structures of different organisms, seeking for drastic, or even the simplest of similarities
and differences. By doing this, they are able to determine how closely related two or more species are. This
doesn’t necessary mean two species are related. There are three main types of structures biologists look at when
studying anatomically: Homologous structures, analogous structures, and vestigial structures. Homologous
structures are most common—they are different structural features with a common evolutionary origin. For
example, a whale forelimb, crocodile limb, and bird wing are very similar, but the organisms are obviously very
different. Analogous structures are those that do not have common evolutionary origins, but have similar
function, such as bird and insect wings. Lastly are vestigial structures. These structures are in present day
organisms but have no distinct purpose, though it probably served a purpose to an early ancestor. A perfect
example of a vestigial structure is the human appendix once used to digest rough substances. “Ninety-nine
percent of the proteins, carbohydrates, fats, and other molecules of living things are made form only six of the
nine-two most common elements.” These proteins make DNA, the genetic code. “DNA contains chemically
coded recipes for creating proteins.” By discovering the genetic make-up of a species and comparing it to that of
another species, paleontologists are able to see the major chemical similarities between living things. These
common characteristics lead scientists to assume that they “either share a common ancestry or they came into
existence as a result of similar natural processes.”Different parts of the body of different organisms are
observed and compared. For example, scientists would look at two different types of tropical birds on two
similar islands. These birds would have similar traits, but would have adaptations called variations in order to
help the birds adapt to certain situations. These variations, changes, help to prove the theory of evolution. “If
evolution has occurred, there should be many anatomical similarities among varieties and species that have
diverged from a common ancestor.” In this line of evidence, the species with the most recent common ancestor
would share the most traits. Those who share the most traits are thought to be the most closely related species.
The anatomy of organisms has led scientists to some unexpected similarities amongst species—by examining
the human hand and comparing it to a bat’s wings, scientists uncovered the possibility of humans and bats being
evolutionarily related.
"Anatomy and Evolution of the Woodpecker's Tongue." The Talk Origins Archive.
N.p., 2003. Web. 31 Mar. 2010. <http://www.talkorigins.org/faqs/
woodpecker/woodpecker.html>. Koentges, Georgy. "Evolution of anatomy and gene
control." Nature. N.p., 2008.
Web. 31 Mar. 2010. <http://www.nature.com/nature/journal/v451/n7179/full/
451658a.html>.
Embryological Evidence
“The pre-mature and the pre-historic”
Eating eggs is tampering with evidence of evolution! Embryological evidence is another method used to
explain evolution. Scientists do this by comparing the embryos of different things in order to see if they are
alike. An embryo is an organism in its very early stages of development. Almost all organisms have evolved
from embryos. The zygotes, the result of fertilization, are the fastest series of visible evolution that will occur in
the organism’s life time. Observing an embryo is like watching real-life evolution. Embryology is the study of
embryos while they are developing. It is in the embryonic stages that new sequences form. Variation may occur
at an early developmental stage. In the early stages, embryos seem to develop almost identically; “such physical
similarities indicate that are genetic similarities between the organisms.” This evidence shows the high
probability of the organisms descending from one common ancestor. For example, the embryos of a fish, turtle,
chicken, pig, and human are studied. The fish embryo was extremely different than the other three, mainly
because it is a marine animal. The turtle’s embryo develops its own shell, in the later stages.
Embryos that are most alike are the most closely related. The study showed the similarity in the embryos
of pigs and humans; though the adult structure is extremely different. The similarity of some organisms, such as
the pig and human, shows their ancestors could have been the same. Different species in the same class are
oftentimes quite different from one another. Darwin’s theory that species change over time, adapting to their
environments by a series of variations is proved by the study of embryos. The embryos of more common
species are studied and it is shown that they grow at relatively the same rate, and adapt features that are very
similar. Though the similarities are most significant, the differences are there. The minor differences in
relatively close species show the variations that evolved in order for that species to properly function—this is
proof of Darwin’s theory. Ernest Haeckel was the most prominent researcher embryonic evidence in evolution.
He had the idea that natural selection and evolution mean the same thing. Haeckel was an evolutionist, but not
so much a Darwinian in that he didn’t believe many of Darwin’s theories. The studies of these variations
amongst different organisms help prove the theory of speciation and homology. Speciation is the evolution of
new species, and is proven by the different evolutionary branches, including embryology.
"Embryology and Evolution." The Creation Research
Society. N.p., 2000. Web. 31
Mar. 2010.
<http://www.creationresearch.org/crsq/articles/36/36_2/
embryology.html>.
"Ernst Haeckel ." UCMP. N.p., 2006. Web. 31 Mar. 2010.
<http://www.ucmp.berkeley.edu/history/haeckel.html>.
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N.p., n.d. Web. 26 Mar.
2010. <http://bioweb.cs.earlham.edu/9-
12/evolution/HTML/live.html>.
Biochemistry as Evidence
“Where bio meets chem. And chemistry meet evolution”
Throughout modern history, scientists have been coming up with crazy theories and many different
experiments. These theories and experimental tests and research labs have helped discover a lot of information
otherwise unknown. “The idea of biochemistry started with the idea of chemical evolution developed by J.B.S.
Haldane, a British scientist, and his theory of chemical evolution is life transpires as the natural process of the
evolution of inorganic matter.” Scientists uncover genetic make-up of organisms by identifying the chemicals in
certain proteins. By detecting the similarities in proteins, scientists can see what organisms are closely related.
Blood proteins, for example, can show evolutionary relationships. “There are a variety of different avenues of
biochemical evidence for evolution, but most of them are either examinations of genetics or of proteins —
genetic homologies and protein homologies.” Similar gene sequences point to similar ways during development.
When viewing gene sequences, scientists and researchers can find gene mutations. A gene mutation is an error
in the genetic code, or DNA. The more closely related a species are, the more alike their genetic material. This,
too, proves the origin of new species (speciation). Scientists look also at psuedogenes to as evidence that
supports evolution. “Psuedogenes are genes that are part of an organisms DNA but that have evolved to no
longer have important functions.” Another example from biochemistry that supports the theory of evolution is
called the universal cytochrome. Cytochrome C is present in almost all life forms, and is essential for aerobic
respiration. A compound’s presence is various life forms show a common ancestor, also helping to prove the
theory of evolution. Carbon-dating is also another form of biochemistry used to prove evolution. Using complex
sequences and equations, scientists are able to date substances based on age of isotopes. This is mostly used to
age fossils in archeological sites and is mostly done on fossils. By knowing the age of materials, scientists can
see and compare them to present day materials. Biochemistry also plays a role in determining the origin of life.
Simple sugars and alpha-amino acids combined under the gases of Earth’s condition to create a life form—but
his is merely a theory. This plays a key factor in the study of evolution. Homology refers to any similarity
between characteristics of organisms that is due to their shared ancestry. Together, embryology, anatomy and
fossil evidence all come together to prove the theory of evolution and how life began on this planet.
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n.d. Web. 31 Mar. 2010.
<http://techcenter.davidson.k12.nc.us/spri
ng026/biochem.htm>.
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