The Opelousas courier., 1905-07-22
A new LAW OF EVOLUTION,
RECENT DISCOVERIES ARour
MAMMALIA OF ANCIENT
AMERICA,
me lime OF the Arrival and Depar
ture OF the Larger and Smaller
Quadrapeds of This continent-rhe
Theory of the Multiple Races,

froI. Il. F. Osborn before the Phila.
delpn1a meeting of the Society of
Naturalists is printed in Science. He
spoke OF the great progress which
mas been made in our knowledge q
mammalian life of ancient North Am.
erica, respectfully through the explora
lions carried on by the Carnegie, Field
Columbian, and American Natural
History Museums in the Rocky Noun
tain regions. y
The long Tertiary period, he said
mad been clearly sub-divided into a
series of stages and sub.stages, which
enabled psychologists to RECORD
o accurately than ever before the
tlme OF arrival and departure of the
larger and smaller quadrupeds from
North and South America, Asia, Eu.
rope, Africa, and to determine more
precisely when the connection OF
North and South America was inter.
rupted by a gulf flowing between the
Atlantic and Pacific oceans, and when
the connection was made again by the
elevation of the Isthmus of Panama;
this demonstrating also that a very
much closer connection existed be,
tween the animal life Of Europe and
North America through continuous
Interrogation over the broad land
area now submerged beneath the Beh.
ring Straits.
Of special interest was the recent
discovery by the Geological Survey
of Egypt that the whole rae of mas
todans and elephants originated in
Africa, entered Europe in the middle
Of the Tertiary, and soon afterWard
found their way into North America
and somewhat later into South Ameri,
ca. Professor Osborn said further
that successive waves of migration OF
European and Asiatic species of ele-
phatS and mammOths came to this
country. In the meantime there had
survived in this country until com
p%aratively recent times from one Oh
the earliest African migrants the
eastern American forest m%astodon.
In regard to the theory of multiple
Or polyphyletic evolution, not
only of elephants, but Of horses, rhi-
noceroses, camels, and titanotheres,
which has been clearly established
through recent discoveries, Professor
Osborn said:
1T was formerly believed, for ex-
ample, that the modern horse had a
single line Of ancestors extending
back into the Eocene period; now it
appears that in North America there
were always four to six entirely diff
ferent varieties of the horse family
living contemporaneously, including
slow-moving, forest-living horses with
broader feet, and very swift plains
living horses with narrow feet 1asn-
toned more like the deer. lntermedl-
ate between these was the variety
which survived and gave rise to the
true modern horse. Furthermore, IL
appears that the modern horses sep
arated from the asses and Zebras at
a much more recent period than has
been generally supposed, and we are
now endeavoring to ascertain accur-
ately when this separation occurred
Professor Osborn declared that In
stead of a single line of evolution
there were at least seven or eight
nearly contemporary but dlstlnct
types of rhinoceros succession, and
then said:
another remarkable feature OF this
law of multiple evolution is that even
where these varieties have evolved
auite separately and Independently,
they still have inherited from remote
common ancestors certain tendencies
or potentialities Of evolution Wnlch
were latent but not expressed IN the
ancestral forms, but which n d
more or less simultaneous expression
in derived forms. Thus, among the
r~binoceroses and titanotheres the ru-
diments of horns begin to appea.
more or less simultaneously IN sever
al of these multiple independent races
or varieties, indicating a hereallaiy
predisposition towards the oeVeiop-
mont of certain organs quite unsus-
pected in the earlier evolutionary
wrr,1ngs of Lamarck and Darwin.
This predispcsitlon to evolve certain
r+r,otures tends to establish the IDEA
that tho laws of development are not
controlled solely by the survival OF
the fttest as according to the original
theory, nor by the inherit
ed effects of use and disuse as &C
cording to the Lamarck-Spencer theo'
ry. but represent the budding out OF
e~ynrass:on Of certain innate or IN
heritad ancestral tendencies.
"Among the many difficult and stun
,nsolved problems is the case OF the
total extinction of the horse in Nortn
and South America, while it survived
and multiplied in Europe, ASIA anu
Africa .tust before the time OF the
extinction of the horse, America eA-
bihited the greatest beauty and va
rietv in 1ne development OF this 1am-
;lv AS studied by Gidley, there were
horses exceeding in size the enor-
nous p%ercherorons of today, ana
tbere were also varieties slhaiiei
the most diminutive Shetlanas.
Vet with all this wide range Oh saiia-
ton all became extinct.
"The elephants also exhibit three
oreat varieties, the true mammoth
m nrimigenids) to the north, tne
Columbian elephant in the ceheia,
States, and the gigantic lmreriai
aammoth to the south, forms shown
- ha quite aistinct by Lucas ana un.
so.htod1v adanted to various kinds OF