1 Running head: LITERARY REVIEW 4 LITERARY REVIEW Natural selection maintains functional characteristics in ant species Ashley Contreras July 21, 2017 Henry Vo Natural selection maintains functional characteristics in ant species. The purpose of this review is to identify if natural selection plays a part in maintaining the status quo among ant populations. While it was initially thought that Random Genetic Drift could have a hand in maintaining functional characteristics, evidence shows that this is unlikely. Random Genetic Drift is an evolutionary process where genetic variations occur over time in a random manner. This process occurs under weak selection, affecting certain characteristics. This means that this process would be unimportant in maintaining functional characteristics. It is, therefore, thought that stabilizing selection, which is a form of natural selection, is responsible for maintaining functional characteristics. (Fisher, 2013). Comment by Contreras, Ashley M: Should be at the end of this paragraph. Start with an intro to natural selection Comment by Contreras, Ashley M: Describe the link between this selection and ant population then details can be discussed in the body Some of the most important functional characteristics of ant species include a pair of leg spurs. These consist of a comb and a brush used for grooming. Grooming is essential for the ant as it helps in cleaning the highly sensitive antennae. With dirty antennae, the insect cannot follow a trail, smell food or even communicate with others. The font spur removes different sized particles from the antennae. The spur is covered with different types of hairs which make it resemble a lobster claw. When the antennae are pulled through this spur, particles of different sizes are removed and the insect can communicate effectively and as well, follow trails. The role of natural selection in maintaining the functional characteristics of the ant species can be identified by observing the genetic variations related to these parts. In most of the ant species, an insect has two pairs of spurs; a front spur, and a hind spur. Observing the genetic variation of these pairs of spurs could help in identifying the force at play in maintaining these functional characteristics. If both the front and the hind spurs are maintained by one force, then it can be expected that they do not show any genetic variations. (Freedman, 2007). Comment by Contreras, Ashley M: These three should be rewritten to become one topic sentence Comment by Contreras, Ashley M: Should be the topic sentence Comment by Contreras, Ashley M: Discuss genetic variations? You have only talked about their phenotypic variations A research conducted on two molecular-phylogenetically indiscriminate ant species suggested that there could be different selective forces acting at different parts of the body of the ant species. The ant species used in this research had spurs projecting from the legs. The f ...

1. 1
Running head: LITERARY REVIEW
4
LITERARY REVIEW
Natural selection maintains functional characteristics in ant
species
Ashley Contreras
July 21, 2017
Henry Vo
Natural selection maintains functional characteristics in ant
species.
The purpose of this review is to identify if natural selection
plays a part in maintaining the status quo among ant
populations. While it was initially thought that Random Genetic
Drift could have a hand in maintaining functional
characteristics, evidence shows that this is unlikely. Random
Genetic Drift is an evolutionary process where genetic
variations occur over time in a random manner. This process
occurs under weak selection, affecting certain characteristics.

2. This means that this process would be unimportant in
maintaining functional characteristics. It is, therefore, thought
that stabilizing selection, which is a form of natural selection, is
responsible for maintaining functional characteristics. (Fisher,
2013). Comment by Contreras, Ashley M: Should be at the
end of this paragraph. Start with an intro to natural selection
Comment by Contreras, Ashley M: Describe the link
between this selection and ant population then details can be
discussed in the body
Some of the most important functional characteristics of ant
species include a pair of leg spurs. These consist of a comb and
a brush used for grooming. Grooming is essential for the ant as
it helps in cleaning the highly sensitive antennae. With dirty
antennae, the insect cannot follow a trail, smell food or even
communicate with others. The font spur removes different sized
particles from the antennae. The spur is covered with different
types of hairs which make it resemble a lobster claw. When the
antennae are pulled through this spur, particles of different
sizes are removed and the insect can communicate effectively
and as well, follow trails. The role of natural selection in
maintaining the functional characteristics of the ant species can
be identified by observing the genetic variations related to these
parts. In most of the ant species, an insect has two pairs of
spurs; a front spur, and a hind spur. Observing the genetic
variation of these pairs of spurs could help in identifying the
force at play in maintaining these functional characteristics. If
both the front and the hind spurs are maintained by one force,
then it can be expected that they do not show any genetic
variations. (Freedman, 2007). Comment by Contreras, Ashley
M: These three should be rewritten to become one topic
sentence Comment by Contreras, Ashley M: Should be the
topic sentence Comment by Contreras, Ashley M: Discuss
genetic variations? You have only talked about their phenotypic
variations
A research conducted on two molecular-phylogenetically
indiscriminate ant species suggested that there could be

3. different selective forces acting at different parts of the body of
the ant species. The ant species used in this research had spurs
projecting from the legs. The front spur is used to clean a
sensory organ, the antennae, while the hind spur are
occasionally used to clean the back surface of the ant’s
abdomen. Given the importance of the front spur of the ant, due
to its use in cleaning a major sensory organ of the ant and hence
it unique brush-shape, natural selection forces can be assumed
to play a big role on this spur. The hind spurs, on the other
hand, have less functional importance. Natural selection forces
can, therefore, be assumed to have no effect on the hind spur.
(Phys.org, 2016). Comment by Contreras, Ashley M: Be more
specific, my impression up to this point is that there are
variation in phenotypes, but not clear on the factors that affect
the genes/genetics to cause these variations Comment by
Contreras, Ashley M: Discuss natural selection forces in details,
this should be the focus of this review
There were significant differences between the two species of
ant. This implied that gene flow between the two-ant species
was highly limited. In addition to that, there was no evidence of
inbreeding within the ant species. This was evidence that any
morphological difference observed within or between the
species populations was not a result of breeding or the flow of
genes. These differences instead portrayed the impact natural
selection has on these species’ characters. A comparison for
both the front and hind spurs in the ant species showed that the
front spurs had only a small degree of variation in terms of the
length of the spur. However, the hind spurs, which are less
important compared to the front spurs, showed significant
variation in terms of length. This suggested the effect of the
random genetic drift. (Darwin, 2010). Comment by
Contreras, Ashley M: This should be a topic with more
discussion within this paragraph, rather than a conclusion at the
end
The conclusion was that there was a stabilizing selection force
at play, which works to maintain the shape and size of the front

4. spur in the ant species, which is highly useful in cleaning the
antennae. The hind spur is not influenced by the stabilizing
selection force. This is because the hind spur of the ant species
has diversified over time. The stabilizing selection involved
here is mostly associated with polygenic traits. The spur in the
ant species is a polygenic trait. (Freedman, 2007). The fact that
the ant species show uniformity in the front spur suggests that
some other force must be acting on the Spurs to maintain the
size and shape due to their importance. The major characteristic
of stabilizing selection is that it favors the population of the
species that is widely adapted to a certain environment. It often
lowers diversity in the species because it leads to some kind of
uniformity in a particular trait. For example, in the ant species,
it leads to uniformity in the front spur. (Freedman, 2007).
Therefore, as opposed to Random Genetic Drift, natural
selection plays an important role in maintaining the functional
characteristics, especially in the ant species. Given its high
functional importance, the front spur needs good maintenance
compared to the hind spur. The genetic variation between the
two pairs of spurs is what led to the conclusion that a different
selection force is acting on each pair. The front pair is
associated with natural selection due to its importance (Gibson,
& Gibson, 2009).
References Comment by Contreras, Ashley M: The
references need to be in alphabetical order
Top of Form
Top of Form
Fisher, R. A. (2013). Genetical theory of natural selection.
Place of publication not identified: Hardpress Ltd.
Top of Form
Freedman, D. (2007). Natural selection. New York: Hyperion.
Top of Form
Gibson, J. P., & Gibson, T. R. (2009). Natural selection. New
York: Chelsea House.
Top of Form
Darwin, C. (2010). On natural selection. Camberwell, Vic:

5. Penguin.
Phys.org, (December 20, 2016). Stabilizing evolutionary forces
keep ants strong. Phys.org - Science and Technology News,
2016-12.
Bottom of Form
Bottom of Form
Bottom of Form
Bottom of Form
Bottom of Form
Excellent Proficient Sufficient insufficient
Title
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Cites the author’s name, date

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2 pts
Title is unoriginal or
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Used 5 – 10 of mostly, primary
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Gathered sufficient
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7. mind.
Used at least three
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Gathered information that
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Little variety in sources
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Body of Text
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13 pts
Draws conclusions from

8. the information.
Information is organized.
Shows skill in approaching
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10 pts
Conclusions are predictable
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while present, is awkward,
jumbled and/or confusing.
Logic may be confusing or
invalid
5 pts
Draws no conclusions
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Writing Proficiency
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15 pts
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Precise and effective use of
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13 pts
Effective use of grammar,
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Meets length requirement

9. and format. Ideas are well
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References
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