Evening star., 1928-12-27
LAWS OF GROWTH"
RESULTS ARE GIVEN
Social Agencies, Humans,
Animals and Plant Develop
ment Called Similar.
by the Associated Press.

by the Associated Press.
NEW YORK, December 27.-NeV
evidence of the power of the laws o
growth, heredity and instinct was pre-
Sented today to the American Associa
ton for the Advancement OF Sclenc'
and affiliated societies.
Indications that social institutions
human beings, animals and plants al
are subject to similar laws of growth,
which govern their periods Of develop
ment, maturity and decline. We're ad'
vanced by DR.. F. Stuart Chapn OF Int
University of Minnesota.
He suggested that II such law
could be established for social mstltu-
tions, it would become possible to predict
Rnd control their future development.
His findings, described as ''prehml'
a1ary," were based on study OF changes
affecting the commission plan OF gov
ernment, the city manager plan,. the
government of Minnesota, and the CITY
growth of Detroit, which he compared
with changes that occur In annnalS De-
tween birth and death.
Our study shows" he said, that the
total changes of four political lnstltu-
tions for period of years may be de-
scribed as a growth tendency not unlike
the growth principle Of animal
organisms"
Heredity Instinct.
Prof. Austin Ralph Middleton of the
University of Louisville demonstrated
that an hereditary tendency lasts at
least as long as the time required to
breed it.
His experiments were made with q
gle-celled creature called parameclum
{hraa Of those animals were
fed on different diets for about month,
they developed different rates Of birth. "
A paramecium really has no birth. "
in the ordinary sense, but about once a
day divides into two cells, each of which
Is an adult. After changing these nor
NAL periods of cell division into periods
of different length, Prof. Middleton took
away the special diets which brought
this about and returned all three groups
to their normal diet The newly acquired
birth rates. however, persisted in each
group "as long as or longer than" the
time required to develop the traits.
virginians Tell of Tests.
Two other investigators, Prof. Will
aiam A. Kepner and j. w. Nittycombe of
the University of Virginia showed that
a basic instinct can live on through
generation after generation even though
the reason for its existence has been
removed.
They experimental with complex
instinct involving both theft and self
protection in a species of worm. This
creature normally kills and eats small
animals known as hydra, which nave
stinging substances in their bodies for
protection.
After the worm has eaten the hydra,
1t appropriateS the protective stingers,
which appear on its own body. For 81
generations, however, worms of this
species were kept without need of hydra
eating, either for food or self-protection,
but when members of the twenty-second
generation were given chance, they
instinctively ate the hydra and took
possession of its protective stingers in
the normal fashion.
Attempts to destroy the instinct were
made by cutting worm in two and
allowing the tail half to grow into a
new worm, and by keeping the worms
from mating, causing them to reproduce
only by dividing into two worms. The
instinct to consume hydra, however.
survived even this test, the University of
Virginia scientists asserted.