Evening star., 1932-02-29
BUTTERFLIES SHOW
MANL|KE TRAITS
Have Own Loves and Hates,
Bachelors Organize
Into "CIubs."

Butterflies have their own loves,
hates and individual peculiarities.
Results of an intensive study extend
ing over many years Of the butterflies
of the District of Columbia by Austin
Clark, National Museum curator, have
just been published by the Smithsonian
Institution.
Clark has spent most of his spare
time for many years studying the Dis
trict butterflies as living creatures
rather than as museum specimens. In
the world of the butterfly, he finds, there
are close analogies to the world OF hu-
man beings. He does not, of course,
attribute to the insects any deliberate,
reasoned judgments which vary their
behavior, but among them the operation
of instructive forces results in some be-
havior not greatly different from that
observed in human society.
One of the phenomena explained by
Mr.. Clark'S investigation is that OF the
puddle butterflies" The shrinking
mud puddle of late Summer with these
insects grouped about it in little COM
panies, each consisting only OF single
species, is familiar sight.
Similar to Mems Clubs.
Clark found that these mud puddle
assemblies might be compared to mems
clubs with open bars in the human
world-havens of peace for harassed
males and of escape for misfts who can
not make a place for themselves in the
hectic workaday world of butterflydom.
He found that the puddle butterflies
were all bachelors = mostly young
bachelors. Furthermore the all seemed
remarkably congenial although belong
ing to species which sometimes are
quite pugnacious in the fields. The pud-
die clubs, he discovered, are much more
numerous as result of population
pressure, although the phenomenon be-
comes noteworthy long before there is
any real danger to the food supply.
In many species OF butterflies he
says the males, if they increase
beyond certain number, seem to be
unable to live together peacefully in
the presence of females, although they
are perfectly we'll able to live together
if they are in areas devoid of females.
This, in part at least seems to account
for the puddle butterflies.
Collect After Rains.
puddle butterflies late in Summer
will collect shortly after rain, when
there can be no question of suficiency
of water in the fields. No matter how
dry the country may be, however, no
puddle butterflies will be seen unless
the puddle species are very common.
THE true explanation seems to be
that the puddle butterflies are males
from overpopulated areas in which they
are necessarily tormented by other
males and from which they escape
to more PEACEFUL surroundings. Re-
quiring water, they naturally resort
to the puddles about which, in the alb
sence Of females, they fail to develop
their usual pugnacity and instead be-
come gregarious, hocking with others
of their kind or with males of several
kinds until they become fully mature,
when they either return to the field
from which they were driven or, re-
manning more or less gregarious,
wander away. Their appearance is
always evidence of an excess of pop
ulation in a given area"
A closely related phenomenon, Clark
found, is that of the roadside butter
flies" These also, he says, turn out to
be nearly all young bachelors driven
out of the fields, but they always are
exceedingly pugnacious. For the most
part they represent different species
than the puddle butterflies. They ap-
pear to be innately incapable Of getting
along together-presumably racial
trait. 1t is noteworthy, however, that
the exiled bachelors of some species
are about equally represented in the
puddle clubs and along the roadsides.
This appears to be the result of in
dividual temperamental differences
among butterflies Some individuals are
difficult to irritate and like boon COM
panions. Others will fight at the slight
est excuse and prefer to lead lonely
lives.
Moisture Aid Escape.
Another phenomenon cleared up by
Mr.. Clark's investigation Is that Of the
enormous increase of some species OF
butterflies following storms. This is
especially true of the common milk
weed butterfly. Most of the population
increase comes from insects newly en-
erged from the chrysalids. 1T would
seem evident" he says, that the moS-
ture provided by a shower enables many
of these insects, previously prevented
from emerging by the dryness, to escape
from the chrysalids. In the cases l
have studied it could not be due to the
normal appearance Of late brood, as
this normally takes place gradually over
several weeks"
Butterflies. like birds and certain
varieties of mammals, have their nligra-
tions, Clark found, but these movements
differ in essential details from those OF
the higher animals.
Bird migrations," he reports, "are
movements of very definite nature
from the breeding grounds to another
region more or less remote, and back
again by the same route. The round
trip is completed several or many times
during the life of the individual, and
the movement usually involves all the
normal and healthy individuals Of a
species in a given area. Butterfly mi
grationS rarely involve more than a
portion, and often a relatively small
portion, Of the individuals in any
region. So far as the individuals are
concerned, the migrations are in one
direction only and, SO far as the species
Is concerned, there is seldom any indi-
cation Of definite return movement.
In some butterflies migration is regu-
larly recurrent annual phenomenon.
In others it takes place frequently but
at irregular intervals, while in many
it is observed only occasionally"
Taking as a typical example of a