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>
.
"Evolution:Evidence From Living Organisms." BioWeb. N.p., n.d.
Web. 26 Mar.
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. Scientist study different body structures of different organisms, seeking for drastic, or even
simple similarities and differences. By doing this, they are able to determine how closely related two or more
species are. “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.”a These proteins make DNA, the genetic code.
“DNA contains chemically coded recipes for creating proteins.”b 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.”c 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 similarties among varieties
and species tha have diverged from a common ancestor.”d 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. This 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. The anatomy of organisms to determine evolutionary patterns is the most direct type of
evidence.
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.”a Almost all organisms have evolved
from embryos. Embryology is the study of embryos while they are developing. In the early stages, embryos
seem to develop almost identically; “such physical similarities indicate that are genetic similarities between the
organisms.”b 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 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. 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.
Embryological evidence as not as easily seen as other types of visual evolution.
Biochemistry as Evidence
“Where bio meets chem. And chemistry meets 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. 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 can show evolutionary relationships.”a Similar gene sequences point to similar ways
during development.b 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.
Scientists look 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.”c 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. Carbondating 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. This plays a key factor in the study of evolution.