Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-02-03
TRACE LIFE TRAIL
6OO,OI)D,ODID YEARS
Carnegie Institution Expedi-
ton Makes Important Dis
CoverieS in Grand Canyon.
BY THOMAS r. HENRY.

There was abundant life on earth
more than 600,000,000 years ago.
Finding of we'll preserved plant fos-
sis and limestone formations, unques-
tionably secreted from plants, almost
at the extreme frontier to which it has
been possible to trace into the past the
trail of living things. is announced by
the Carnegie Institution of Washington,
as the result of recent expedition into
an almost inaccessible valley in the
Grand Canyon of the Colorado River
But in this dark valley they were
confronted with a great enigma of geol-
ogy Here if anywhere, they had ex-
pected to find earlier animals than any
now known to science. They found only
blank pages in the rock. 1t is as if
animals we're suddenly thrust on earth
out of nowhere, although the paleontol-
ogists are certain nothing like this hap
pened.
Such were the findings of DR.. David
White of the National Academy Of Sci
ences, who for several years has studied
intensively the remains of very ancient
life in the Grand Canyon, and DR.. c.
E. Resser of the United States National
Museum, who led the recent expedi-
tion.
Animal Life Abundant.
Approximately 100000 years ago,
DR.. Resser explained. were laid down
the rocks known as the Cambrian.
Their age can be estimated roughly
from the rate of disintegration of ra-
dunn. During the long ages other rock
formations have been laid down on top
of them. but here and there they crop
out on the surface. In these rocks ami
NAL life was abundant, chiefly sea crea-
lures allied to the modern crabs, But
these trilobites were far advanced in
the scale of animal life. They must
have had many thousands of genera
lions of ancestors. But where did they
come from?
There are still cider rock formations
the pre-Cambrian. In the undisturbed
sequence of nature the Cambrian rests
on top of them. They must be millions
of years older but there is no way of eS-
timating their age with much reliability
In the vast extent of time they repre-
sent it would be expected that the an
ceStors Of the trilobites c-uld be found.
Like the Cambrian, the pre-Cambrian
rocks jut out on the surface here and
there. But, DR.. ResSer explains, they
are so old and such tremendous pressure
has been piled on them through the
ages by the younger rocks that what
traces OF life they may once have held
have been almost obliterated. Especially
is>this true where they have been sub
jected to the physical forces which
would serve to bring them out of their
great depths to the surface. They are
greatly metamorphosed. Traces of plants
have been found, but nothing that can
be accepted with certainty as the re-
mains of an animal.
Ideal Spot Located.
But in the Nankoweap Valley, seldom
visited by white man, curious con-
dition had been reported. Several thou
sand feet of strata were exposed be-
meath the Cambrian. These beds were
never covered with Neat thickness Of
younger strata, and their originally
horizontal position was disturbed by
only one fault and the gentle curva-
ture of the Kaibab fold Thus they had
escaped being metamorphosed by squeez-
ing. 1t was one Of the most favorable
spots in the world to find traces of the
oldest animals.
DR.. Resser found plenty Of spongy
masses of limestone which were Sc
creted by the blue-green alga. primitive
plants whose descendants still are busy