Iowa County democrat. [volume] (Mineral Point, Wis.) 1877-1938, 1893-08-18

The production of sounds in ants
If we consider that ants have the facul-
ty Of producing a sound perceptible to
our ear by rubbing a part of the body,
the hypothesis that these insects pos
sesS also the faculty of hearing ac-
Quires a certain likelihood. Landois
and Lubbock mention as probable what
produces this sound is in the posterior
part Of the insects body. Yet they
furnish no proof Of it. 1t, therefore,
appears to us of interest to quote the
following short passage from a work
by Robert Wroughton upon the noise
produced by ants in the Indies:
Il am almost certain of having heard
these sounds. When one of the gray
paper nests of Cremastogaster regen-
hoferi is suddenly and violently shak-
en-, the ants escape by thousands, NOV
ing their abdomen in the manner so
characteristic of the species of the
genus when they are excited. From
time to time there is distinctly heard
/
were being plunged in water. I had al
ways supposed that this noise was
caused by the friction of the legs of
! the ants against the sides of their
nest. An analogous, though feebler
sound may be perceived when a large
nest of CampOnotuS or POlyrhachis
spinigera is disturbed. 1t is produced
| NV f1,o FIJI Of fhn If
the ants, which suddenly enter into
active motion. However, the passage
from Lubbock that I have just cited
leads ME to think that there is nothing
in this but that the noise heard is
produced by the mass of innumerable
ants. The motion Of the tail of the
Cremogaster would explain why the
noise that they make is louder, al
though they are much smaller than
the CompOnod or the Polyrhachides.
/ asked Mr.. Aitken to make some ex-
periments in order to confirm the re-
suits that [ thought / had obtained
He will, doubtless, recognize in the fol
/ lowing note, confirming my assertions:
81 have no need of making an expert,
/
of Lopobiltae, when they are stirred
up with a straw, is heard without ne
cessity of placing the ear close by. ]
should like, however, to know some
thing as to the nature of those organs
What is their role? Are they military
drums?"
/ Twenty years ago, Mr.. Auguste Forel
N
a signal alarm, consisting Of a peculiar
noise: Not only do the CampOnoti
strike themselves forcibly, and with re-
peated blows against each other, but,
at he same time, strike the ground
two or three times with their abdomen,
and repeat this act at short intervals,
thus producing a very marked noise
that is heard especially well when the
nest is in the trunk of a tree"
! Forel's theory is confirmed by sew
eral Of my observations upon the Camp
onotus igniperdus, and I have nothing
to add thereto. There is no doubt that
this signal Of alarm is understood by
the ants. Without that it would not be
an alarm signal. But the question is
to know whether the noise perceived
by the ants is perceived as sound
through a sort of hearing, or as a
simple shock by the touch by means
Of 4 slight friction Of the lower limbs
upon the bottom Of the nest. Ants,
in fact, are provided with hairs under
the legs for the purpose of feeling.
In order to elucidate the question, the
examination would be more favorable
if it extended to different species of
our my1mides, which show their anger
by a violent motion of their posterior
legs. They seem to make use of their
first sting for rubbing their metanotum
Unfortunately, the species of which
we have just spoken are almost too
snail, except the Myrmica rubida,
which is too quiet to permit of prov
ing distinctly the production Of sound
in these animals. Two years ago I
published work upon the touch Of
insects. This observation is, perhaps,
still unknown to specialists, and it is
for that reason that I communicate it
here once again.
One very hot day had put a portion
VI d 1dlSe COlOuS VI MY IIluCSt IuSluOulS
into an empty glass globe. The ants
were much agitated and rubbed their
posterior legs violently. On seeing this
motion executed by large number Of
individuals at the same time, / heard
a slight droning that recalled to me
the sounds made by a co1eopter, the
Mononychus pseudacori, which lives in
the gruit of gladioli. Unfortunately,
I did not succeed in renewing this OBJ
servation in the experiments that I
made later on.
We find in a monthly chronological
review a, note by A. II. Swinton on the
sound of the Myrmica rugidinodis and
other Hymenoptera. He observed a
small female worker mot a male, AS
he thought that was violently agitat-
ing its posterior legs. He made an ex-
animation and afterward found organs
that probably produced a sound at the
base Of the posterior legs and Of the
second sting.-E. Wessman, in Biol
gische Centralblatt
Simian or ape-like man-Prof. E. D.
Cope, in the Naturalist, has an article
on this subject He says archaeology,
apart from anatomy, is poor guide in
the field of human ancestry. The clos
er associa ton of man with the apes is
based on various considerations. 1t is
highly probable that the homo is de-