Evening star., 1935-08-31
STARS, MEN AND ATOMS
Notebook of Science Progress in Field,
Laboratory and Study.
BY THOMAS r. HENRY.

Life in the green mansions" of the
Panama jungles amidst troops of bark
ing spider monkeys who drop sticks
resentfully on the heads of human in
vaders is described in a report to the
American Society of Mammalogists by
DR.. c. r. Carpenter of Columbia Uni
verSity.
DR.. Carpenter, noted student of simian
behavior, went to the isolated and
sparsely settled Coto region on the bor-
der of Panama and Costa Rica as fell
low of the National Research Council to
make an intimate study Of the behavior
of the red spider monkeys in their ma
tive habitat. He has made two expedi-
tions during the past four years. On
the second he was accompanied only by
his wife and two natives.
The country in which they made their
camp is one of dense forest occupied by
an abundance of wild life that is almost
entirely unmolested by hunters, as he
recounts in his report just published in
the Journal of Mammalogy. The bal
ance Of nature has been little disturbed
It is a country of tapirS, deer, jaguars,
pumas, ocelots, peccaries and many small
mammals in addition to the great hordeS
of monkeys fitting through the tree
tops. The spider monkey population is
very heavy-eStimated by Dr.. Carpenter
at about 200 square mile.
DR.. and Mrs. Carpenter literally lived
with the monkeys, observing their be-
havior night and day and in all the
activities of life. The most striking prac-
tice observed was that of "stick throw
ing" at enemies.
Says DIR. Carpenter: when approached
these animals typically begin barking.
Frequently they approach the observer,
The usual terrierlike bark of great ex-
citement may at times change to a
metallic chatter repeated with great fire.
quency. When males, and sometimes
adult females, are closely approached,
they may growl in a strikingly vicious
manner. Typically they come to the ter
minal ends of the branches, often to
within 40 or SO feet Of the observer, and
shake the branches. This may be done
with either the hands or feet, or both
hands and feet may be used while the
animal hangs by its tail. Concurrently,
and almost invariably, vigorous scratch
ing occurs.
"The breaking of and dropping Of
branches is a conspicuous part of the
reactions of spider monkeys to man
Very frequently they break on and drop
limbs close to the observer. Any expert
enced native will warn one Of this source
of possible danger. Green branches
sometimes, but most often large dead
limbs weighing up to or 10 pounds,
may be broken of and let fall toward
the observer. One can well imagine the
impact of one of these missiles when
dropped from 40 or so feet above the
ground.
"This behavior cannot be described as
throwing, although the animal may cause
the object to fan away from the per-
pendicular by sharp twist OF its BODY
or q swinging, circular movement OF It's
powerful tan. This dropping OF objects
from the trees with reference to . dis
trbing person may be considered. ap-
parently, as defensive adaptation aris-
ing from the more generalized habit OF
shaking branches. A significant varia-
ton occurs when the animal breaks on
limb and holds It for time, varying
from 3 second to half q minute, before