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\let\liskip\medskip
Antlions organize themselves systematically in response to the
environments where they find themselves.
Individuals attempt to regularize their own pit locations according to
nearby pits and the borders of the living space, and this structure is
affirmed by a statistical test on the uniformity of their distribution.
Using a Monte Carlo simulation of 10,000 randomly distributed patterns
of the same number of pits as observed from each trial, a typical
distribution of the distance to the nearest neighbor was determined.
The distance to the nearest neighbor is approximately independent for
each pit, so a Cram\'er-von Mises statistical test was applied to the
observed distributions, resulting in striking evidence that these pit %'
distributions do not conform to a uniformly random independent
distribution of each pit, with all (except one) distributions of
antlions having $p<0.05.$
\liskip
\li As a result of the statistical analysis procedure, during which the
settlement patterns of antlions in a given trial were compared to a
completely random settlement, a clear correlation was shown between the
settlement patterns of the antlions and environmental constraints.
\li A clear increase in the reclusive population as trial size decreased
was observed in every obstacle condition, as the reclusive population
increased from one ($24\times24$) to two ($12\times12$) during the trail
erasure trial. The same results are shown across the trial with fake
pits, where the number of reclusive antlions increased from one to four,
and the obstacle trial, where the amount of reclusive antlion increased
from zero to three.
\li The number of reclusive antlions increased by an average of 2.333
antlions, or an increase of 233.3\%, which marks quite a significant
change.
\liskip
This change indicates that the introduction of various obstacles and
interference in other modes of communication can change the natural
settlement patterns of the antlions, as a significantly larger number of
reclusive antlions were observed during trials with artificial pits,
indicating that the density of pits in a given area affects how antlions
settle the territory.
This analysis makes biological sense, as by regulating the density of
antlions in a given territory the organisms can reduce intraspecific
competition, which in turn helps the species reproduce more as a whole,
thereby explaining the phenomenon.
Along with this, a dramatic change in the cannibalistic nature of the
antlions was noticed once various obstacles were introduced, for
example.
\liskip
\li It was noted in the previous study that the number of cannibalized
antlions increased by an average of 13.9785\% when the trial size was
reduced with no obstacles or communication interference.
\li This differs from the trend in cannibalism noted throughout the
following trials, as the data clearly shows how the rate of cannibalism
tended to decrease across various trials.
\liskip
This indicates that the antlions' cannibalistic nature is affected by
environmental conditions such as changes in terrain and other obstacles,
which could be a response to an interrupted communication pattern that
results in a closer settlement, which intern would increase the contact
between each antlion, thereby leading to more cannibalism.
Finally, along with a trend in reclusivity and cannibalism, a trend was
noticed in the average pit depth across all trials, as it decreased as
trial size decreased throughout the study, regardless of the obstacles
introduced (\boxplotref).
This indicates that the size of pits made by antlions is independent of
the mechanisms that govern how they settle, as the study was able to
alter all of the settlement patterns of the antlions through the
introduction of obstacles except for the average pit depth, which
maintained a constant pattern through the introduction of obstacles and
the original trial from a previous year.
This indicates that the average pit depth does not depend on their
settlement pattern of the antlion community as a whole, but rather is
dependent on factors such as time and available resources.
Several patterns were also observed in whole antlion group
distributions.
\liskip
\li The average nearest neighbor remained relatively constant across all
trials and environmental conditions, except for when a series of fake
pits were introduced to the environment, as the average nearest neighbor
ranged from 2.1-3.9 (\lineplotref) for all trials except the
$24\times24$ trial with fake pits, where the average nearest neighbor
increased to 8.7.
\li The nearest neighbor, in the fake pits trial, decreased by about 5.5
inches, which differed from the trail erasure where the nearest neighbor
decreased by about 1.95 inches, and the trial where obstacles were
introduced, during which nearest neighbor remains constant.
\li The antlions maintain a non-random distribution pattern across all
trial sizes and environmental conditions, as the antlions near the
middle of the habitat maintain equidistance from their neighbors, a
principle that is evidenced by the centermost pit in each Voronoi
diagram.
\li Voronoi diagrams may also show how the antlions tend to maintain
semi-constant territory size across both changes in environment and
changes in habitat size, as the average territory occupied by each
antlion does not change significantly past a certain maximum density of
pits.
This strategy reduces cannibalism and competition.
\liskip
Based on the settlement patterns of the antlions on both, an individual
and group scale several conclusions can be drawn about the environment's
impact on the settlement patterns of the insect along with the
mechanisms that antlions use to settle in a non-random pattern.
\liskip
\li One of the most interesting patterns in the data
was the impact of fake pits on the antlions settlement, as when fake
pits were introduced to the environment the rate of cannibalism and
reclusivity among the antlion population increased significantly, as
shown by \boxplotref.
\li Antlions tended to space themselves away from fake pits when
settling, represented by an abnormally high nearest neighbor metric
(between real pits) during this trial, as shown by \boxplotref.
\li This indicates that the settlement pattern of the antlions is highly
dependent on the existence of pits around them because the fake pits
trial showed that raised ground and deformities in the environment allow
antlions to decide on their nesting location.
\li This may indicate, in part, mechanical rather than cognitive nesting
mechanisms.
\li Along with this the increase in reclusivity and cannibalism observed
during this trial also indicates that antlions, as individuals, attempt
to reduce the surface density of pits through extreme behavior.
\liskip
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