Biology Review: Evolution + Classification
Individuals who shaped evolution:
 ___________________________: Created the Theory of Use and Disuse and Inheritance of Acquired
Characteristics. He stated the more an organism uses a structure, the more developed it will become. If
they are not using the structure, it will eventually disappear. He then stated that any trait/characteristic
acquired in ones lifetime will pass onto their children.
o Example: Giraffes didn’t always have long necks. He hypothesized that they stretched their necks
to reach the leaves on the higher branches. The stretched neck then was passed onto their
offspring. Needless to say, he was incorrect.
 ___________________________: He is better known as the father of evolution and created the Theory of
Natural Selection. This theory is better known as “Survival of the Fittest”. Fittest means the best adapted
organism or the one with the most desirable traits. Be careful….Fittest doesn’t always mean the biggest
and strongest. It could mean smallest, slowest, etc. BEST ADAPTED FOR THEIR ENVIRONMENT.
The following describes the role of each of the following in developing the current theory of evolution.
 Anatomical comparisons (comparative morphology): Comparing anatomy and finding similarities,
leads scientist to believe that some organisms have a common ancestor.
o ______________________structures: Structures found in organisms that have a common
ancestor. They have evidence of similar structures, the forelimb bones in several organisms.
They have evolved to become their own organism over time.
o ______________________ structures: Structure present in organisms that have no current use,
but are thought to have been used at one time. For example, the pelvic bone on snakes and
whales. Shows common ancestry.
 ______________________________: When comparing fossils for a particular organism (for example, the
horse) change over time is observed.
 _____________________________: When comparing amino acid sequences and base sequences in
DNA, organism with similar sequences are thought to have similar ancestors. For example, humans and
chimps. DNA sequence is very similar.

_________________________________: Formation of a new species due to gene pools being separated
and becoming reproductively isolated. There are several ways in which a population can become isolated:
o ___________________ isolation: populations separated by geographic barriers (water, land, etc)
o ___________________isolation: populations separated by different courtship dances or other
reproductive behaviors.
o __________________ isolation: populations separated by different reproductive times.


______________: study of evolutionary relationships among organisms
______________: Diagram showing the evolutionary relationships among various organisms. Oftentimes
focusing on very specific characteristics.
a. The most primitive organism will be the first branch
of the cladogram: _____________________
b. The most complex organism will be located at the
top or end: _________________
c. The words listed on the lines are defining
characteristics for the organisms. Once a
characteristic is listed, all organisms after that will
have that trait: ___________ – perch, salamander,
lizard, pigeon, mouse, and chimp
d. Which groups have claws or nails?
e. The more closely related organisms will be closer
on the cladogram: mouse is more closely related to
a _______________ than a salamander.

____________________ is the process in which organism are grouped together by similarities.

Seven-level classification systems: Kingdom, Phylum, Class, Order, Family, Genus, Species
o Remember the sentence:
 __________________ is the broadest category and species is the most specific
 ___________________________________ is the universal system used in naming organisms:
o 1) Each organism has two words in Latin which describe their most distinguishing features; these
two are the genus and species
o 2) The genus must be capitalized and the species is lower case
o 3) the genus and species must be underlined or written in italics.
o Example: Homo sapiens, Apis mellifera
 Dichotomous keys are tools used to identify organisms. Always start with #1 and examine the
characteristics listed. Continue with key until organism has been identified.
Kingdoms of Life
Archaebacteria
Eubacteria
Protista
Fungi
Plantae
Animalia
Eukaryotic or
prokaryotic
Multicellular
or Unicellular
Autotrophic or
Heterotrophic
Examples
Prokaryotic
Prokaryotic
Eukaryotic
Eukaryotic
Eukaryotic
Eukaryotic
Unicellular
Unicellular
BOTH
BOTH
Multicellular
Multicellular
BOTH
Extremophiles,
Halophiles,
Thermophiles
BOTH
BOTH
Amoeba,
Euglena,
Paramecium
Heterotrophic
Autotrophic
Moss, Fern,
Pine tree,
Daisy
Heterotrophic
Earthworm,
Whale,
Insects
E. coli,
Stretpococcus
Mushroom,
Yeast
In the following chart, describe the role of each of the following in developing the current theory of evolution.
Discussion of importance to evolutionary theory
Anatomical comparisons
Patterns in fossil evidence
Lamarck’s ideas about
inheritance
of acquired characteristics
Biochemical comparisons
(DNA and proteins)
The role of sexual
reproduction
The role of geographic
isolation
Darwin’s Theory of Natural
Selection
Discuss the steps in Darwin’s theory of evolution by natural selection.
a. Populations of organisms have many genetic variations. Where do these come from?
b. Organisms could reproduce exponentially but they don’t. Why not?
c. Genetic variations lead to different adaptations. What are adaptations?
d. Some adaptations have better survival value in certain environments. What does this mean?
e. Those organisms with adaptations that better fit them to an environment will survive, reproduce and pass on
their genes. What does it mean to be “fit” to an environment?
f. When this process continues over millions of years, it can lead to speciation. What is speciation?
Classification
a. What is the current seven-level classification system?
b. What is binomial nomenclature?
c. How are DNA and biochemical analysis, embryology, and morphology used to classify organisms?
a. To the left is a phylogenetic tree of some organisms.
According to this tree, which pairs of organisms are
most closely related?
b. Which organism is most closely related to the
rayfinned fish?
c. Which organisms are the mammals most closely related
to?
Use the following key to identify the tree branch to the
left.
1. a. leaf is needle-like….go to 2
b. leaf is broad……… go to 5
2. a. needles are short ....go to 3
b. needles are long…...go to 4
3. a. underside of needles green…hemlock
b. underside of needles silver ..balsam
4. a. 3 needles in bundle….pitch pine
b. 5 needles in bundle….white pine
5. a. edge of leaf round.go to 6
b. edge of leaf serrated…go to 7
6. a. minty odor…… wintergreen
b. no minty odor…..laurel