Evening journal., 1921-08-29
HASFAMILY TREE
5000 YEARSOLD
Caenolestes Only Living
Thing Whose Ancestors
Existed Ages Ago
LOOKS LIKE A RAT;
LIVES IN VENEZUELA


what is now South America. Nine
years ago it was discovered by an
exploring expedition of the Field
Museum of Natural History.
The museum has just published its
first scientific report of its find
Speaking OF his discovery. DR.. will
fred H. osgood. OF the Field Mu-
scum. has named some of the fea-
lures.
Through all these ages this ami
NAL has continued reproducing rrself
without important change It is one
of the most notable examples of the
simple life" All the other animals
OF its group have utterly vanished or
been turned to stone hundreds of
thousands OF years ago. 1t dates
back to the period when the warm
blooded animals we're just begin
ming to evolve from the cold
blooded reptiles. 1t is one of the
oldest living mammals.
Like Sharp-Nosed Rat.
A little animal, II looks like a
sharp-nosed rat. II is only about six
inches long, but it's size has helped to
preserve It. It has small eyes. round
ed ears. slender tail and soft.
brown hair. Caenolestes is its name
modern representative OF an an
cient group Of predatory animals.
DR.. Osgood made his discovery in
Venezuela in 1912. He secured his
specimens in the heart Of a dense
forest of the mountains there. Ac-
cess to the spot was gained by la
boriously cutting narrow trails for
long distances through the heavy
underground. Since then DIR. Os-
good has made an intensive study OF
the animal. and It Is this which the
Field Museum has just published in
a book entitled "a Monographic
Study Of the American Marsupial,
Caenolestes."
This little animal Is quite unlike
any other now living in the world"
DR.. Osgood said. Although Il does
not resemble closely any species now
living. 1t is very intimately related
to animals which flourished far back
in geologic time. when the founda-
tons were being laid for the evolu-
tion of the higher animals Of the
present day. All the others OF the
group TO which it belongs became
extinct ages ago and Caenolestes
alone has survived to the present.
I'VE know this because its bones
and teeth are especially the same as
those OF the extinct animals. II the
bones are the same, it is probable
that other parts also are similar.
Therefore. Caenolestes is a prize to
the student, for it enables him to
learn more about the ancient fossils
than is shown by their bones which,
OF course, are the only parts pre-
served.
HarlSs Back 100000 Years.
The length of time it has sur
vived is almost incredible. Its ex-
tinct relatives lived in the Miocene
period. and this. according TO good
authorities. was about 5000, 900
years ago. During all this tremen-
dous lapse of days and nights It has
been able to Withstand the compe-
tition of nature. to find food and
proper conditions OF temperature
and to care for its young-in other
words, to live and reproduce itself.
Its close similarity to the extinct
forms indicates that it has been able
to do this without any serious
change in its physical makeup. The
secret of its success is doubtless tc
be found in the simplicity Of its re-
quirements. It is one of the mos
generalized Of mammals now living
II has never gone 10 extremes, never
! developed any very special tastes oil
peculiarties. II feeds upon insects
and isn't particular whether they
are hard or soft smooth or woolly
Three million years ago, in al
probability, its tastes were the same
and insects were just as easy to find
then as now.
zone Of its assets has been iti
small size. It has seen the giants o
the past come and go while Il wen
serenely on. il never tried any ex
periments. never went Off on a tan
gent and never took any chances
BY always taking the easiest and SAT
est way It accomplished mere exis
tence and nothing else.
, "If all the early mammals had le,
the same simple life the world nov
would not be the sort Of place it is
= Those that developed along specia
lines often found themselves 81
I fatal difficulties. but some of then
Z took the lines that have led to tn
). higher mammals of today. SO far a.
,. evolutionary progress is concerned
L therefore. perhaps Caenoiestes nigh
10 as well have ceased to exist million
OF years ago.
j. Relations i'm Australia
G "Caenolestes belongs to the grea
marsupials or pouched animals. but
e although it lives in America. It Is no
closel. related to the opossums
which are the only other America
marsupials. on the contrary, il
nearest living relatives are the Aus
I tralian bandicoots.
Ia This makes Il interesting in con
nection with theories as to whethe
or not South America and Australi
y ever have been connected by a Ian
se bridge. With marsupials now foun
* both in South America and Australia
I'd several explanations are possible
l. The original stock may have sprea
N from South America to Australia G
ID vice versa by a land bridge no longs
existing. Also IL may have originate
in long-since vanished souther
TX continent. the so-called Atarctici
IT and from there spread northwar
m both to South America and to Au.
m tralia-