The Ely miner. [volume] (Ely, Minn.) 1895-1986, 1932-04-15
FEW ESCAPE FROM
ANT-LION'S TRAP
Insects Effective Method Of
Obtaining Food.

Many of natures most tragic
fights are waged among the smallest
creatures, writes Oliver G. Pike, r.
2. s.. in London Tit-Bits. Some of
our tiny insects set traps which for
ingenuity surpass the inventions of
primitive man.
There is a small insect, which in
the larva state is about half an inch
in length, and known as the ant-lion.
The perfect winged insect is larger
than the larva and resembles a dra-
gon fly. AS it flies a short distance
above the ground it searches for a
sandy site. then deposits one egg, in
a suitable spot. A short distance
away it lays another, and so on I'M
til the full complement is disposed.
When the larva energies from the
egg it sets to work to build trap
into which its prey will fall.
1t first depresses its tail or abdo-
men into the soft sand. Then, walk
ing backwards. it traces a perfect
circle of about two inches in diane
ter. marking the foundation of the
trap. Now. having marked the out
line on the ground. it proceeds to ex-
cavate the interior, making fairly
steep walls which slope down to the
center.
1t is at first confronted with the
difficulty of moving the sand with
out damaging the walls. but it gets
over this by starting in the center
With one of its legs it loads the sand
upon its fiat head, and when this is
almost covered it makes a rapid
movement, fiinging the load of sand
outside the circle.
Working backwards all the time.
1t makes ever widening circles until
conical pit is formed. If it comes
across a stone which completely
blocks its work. it goes outside and
starts another in a more favorable
position. but small stones which
might interfere with the symmetry
of the sloping walls are lifted on to
the head. Then, going carefully up
the walls. ii tips them over the edge
of the outer circle. At last its lair
is complete. and going to the center
it waits patiently for an insect to
fall in.
Ants form its chief prey. If one
Is passing and sees the silent crea-
ture waiting at the base of the con-
zeal walls, it often goes inside to
reconnoiter. but directly it places its
feet over the outer circle, the sand
gives way and it slips down, to be
seized by the waiting enemy.
1t often happens that the ant is
able 70 recover its balance and try
to regain the film ground outside,
but the ant-lion is prepared for this
maneuver. 1t now hurls fine sand at
its prey, and the more it tries TO
climb upwards the more difficult the
feat becomes owing to the sand
showers.
The story usually ends with the
nnt-lion being the victor, but if a
idAiiy 1dISc SplutE eusGTS Tie trap
fierce fight often takes place, with
the odds fairly even. If. however,
the ant-lion is able to get its power
full jaws fixed into it's captive there
is no escape, for these pin the prey
down, and at the same time suck
the juices from its body. The lat
ter is not devoured, but If the car
cass were left inside it would be a
warning to others, so the ant-lion
makes clean sweep of its feast by
flinging the dead insect outside in
the same manner that it disposed
of the sand while excavating.
This small larva, which is found in
southern France, would have little
chance of surviving in the fierce
struggle for existence if it had TO
chase its prey, so it has devised
very effective method for obtaining
its meals. but like all trappers it
has to wait long periods between its
captures. This, however, does not
inconvenience it. for it has the pow
er of fasting for long periods.