constant features of these three sp(!cios
of man. Skin color is less uniformly
distinctive. The Mongolians are yellow
to dark brown or bronzed in skin color.
The Negroids are generally dark brown
to full black. The Caucasians are
extremely fair-skinned in the North,
hght-brown-skinned in the South, very
dark-brown-skinned in subtropical
Polynesian hybrid branches, like the
Hawaiians.
Each of these human species inter-
breeds with the other and produces a
great variety of half and quarter
breeds. Thus inter-fertility is not a bar
to specific distinction or even to generic
distinction in mammals. In the family
of Bovidse, for a parallel, several genera
and species freely interbreed, e.g., our
domestic cattle (Bos taurus) and the
bison (Bison americanus).
CAUSES OF THE DIVERGENCE OF
RACES, SPECIES, AND STOCKS
The color divergence in the Cauca-
sian and Mongolian species is only the
most conspicuous of thousands of
divergent characters which have been
brought about through the long in-
fluences of mate selection, of indirect
adaptation to climate, of the direct
influence of climate, of the influence of
habit, and of 'organic' or coincident
selection. I am inclined at present to
regard the prolonged or secular in-
fluence of habit and of organic selection
as among the prime causes of the diver-
gence of human characteristics. The
opening of the Lord's Prayer, "Give us
this day our daily bread," is a recog-
nition of the world-wide fact that the
NATURAL HISTORY
primitive man must first think of the
food supply for himself and his family.
Exactly like an animal, he is compelled
to work for his food supply, to seek it
where the environment offers it, wheth-
er in the chase of animals or birds, in
fishing, or in the earth. The search for
food has led man into various habits
and habitats to which he was more or
less fitted by intellectual, moral, and
physical predispositions.
These predispositions are hereditary
and therefore subject to organic selec-
tion. By heredity men may be pre-
disposed to arboreal, to cursorial, to
terrestrial, or to amphibious life. The
born climbers take to the trees, the
born swimmers take to the water, the
born runners take to the chase. But in
turn these very habits of tree life, of
aquatic life, of cursorial or running life,
through the process of individual modi-
fication and self-adaptation, are self-
perfecting. Those who attain the
greatest skill and facility are naturally
the most successful members of the
tribe. They are the best climbers, the
best fishermen, the best hunters. They
are rewarded by the first choice of
wives and blessed with the first crop of
offspring. This is the essence of the
principle of organic selection, a sub-
sidiary principle of Natural Selection,
which was independently formulated
by Baldwin, Morgan, and Osborn.^
The illustration which Osborn used is
cited on page 1 1 in 'How to Produce an
Arboreal Type of Man.'
Have we wandered far from our
subject, the evolution and terminology
of human races? Not at all. We have,
on the contrary, come to the very heart
and philosophy of it, because the gene-
sis of human races was exactly like the
'H. F. Osborn: A Mode of Evolution Requiring
neither Natural Selection nor the Inheritance of Ac-
quired Characters. Trans. N. Y. Acad. Sci., Vol. XV,
March 9 and April 1.3, 1896, pp. 141-42, 148.
genesis of animal races prior to the
era of civilization. Following alike the
principle of adaptive radiation, man
goes forth to seek and labor for food.
He may go to the temperate regions, to
the North Pole, or to the Equator. If
he chooses the Equator the quest for
food is very easy and requires relatively
little intelligence; the environment is
not conducive to rapid or varied
organic selection; the struggle for
mere existence is not very keen; the
social and tribal evolution is very slow;
intellectual and spiritual development
is at a standstill. Here we have the
environmental conditions which have
kept many branches of the Negroid
race in a state of arrested development.
The food supply is primarily from
the chase, secondarily from agricul-
ture or the quest of natural fruits.
The Mongoloid races at a very early
stage exhausted their animal food
supply and were compelled to turn to
agriculture. This explains the extra-
ordinary industry, vitality, and work-
ing powers of this people, which are the
result of ages of organic selection. A
Chinese or Mongoloid workman has
far greater endurance and is capable of
more continued effort on less food and
a lower energy (calorie) diet than the
Caucasian, who, until the game supply
began to be exhausted in the forests
and plains of northern Eurasia, was
chiefly a hunter and fisherman.
It is, then, the varied quest for food
which is the prime cause of the evolu-
tion of the specific and subspecific
characters of man. This quest leads
him into certain new environments,
the new environments compel him to
adopt new habits and modes of motion,
and the new habits and modes of loco-
motion produce new modifications and
changes of form which are accumulated
through organic selection and pre-
THE EVOLUTION OF HUMAN RACES
his is not the Laiiiarck-
ic direct inheritance of
disposition.
ian theory o
acquired characters; it is a theory of
prolonged or secular inheritance of
predispositions which happen to coincide
with the new demands and habits of
life. This process of organic or coin-
cident selection operates over very
long periods of time.
The new environments also throw-
all the old adaptations out of balance
and put new survival values on certain
characters. The heavy beard is a
distinct advantage to the Nordic and
to the Alpine hunter. The hairy cover-
ing of the body is of benefit to the Alpine
Slav of the cold plateau regions. On
the contrary, the Mediterranean sub-
species and the Negroid specie.^ develop
hairless bodies, partly because hair is
unnecessary with a very dark skin,
partly because hair and clothing harbor
insect carriers of infectious diseases,
from which it is ea,sy to protect the nude
and hairless body. The Mongoloid
races, although partly migrating into
the coldest regions of the earth, have
never acquired a hairy covering and
are as hairless as the Negroids; the
same is true of the American Indian.
Individual choice of habit and of
habitat, with men as with animals,
has by these means been the poles tar
of evolution. Lamarck in a secular or
geologic sense was right when he said
that organs were acquired when animals
strove for them; they are first acquired
as non-heritable modifications; in the
course of ages they are acquired as
true hereditary characters. This choice
of habit or of habitat has sometimes
been optional, a matter of pleasure in
choosing between two or more alterna-
tives, and sometimes enforced. Alden
Sampson has shown that the white-
tailed deer (Odocoileus macrourus) of
the western states seeks no less than
seventy-three kinds of food during the
course of the year. Among the ante-
lopes of Afi'ica there is a great seasonal
range of diet for certain species; others,
like the Oribi, are said to browse only
Photograph by Underwood and Underwood
RUNNING TYPE
Paavo Nui'mi, Finnish runner. Observe
the feeble arms and strong legs
on a single kind of plant to which the
animal is exclusively adapted. iVIan,
like the bear, is naturally omnivorous,
but he may be forced to an exclusively
frugivorous diet, as among the plan-
tain eaters; to a strictly graminivorous
diet, as among the rice eaters; or to an
exclusively flesh and fat diet, as in the
case of the most northerh^ Eskimo.
An exclusive diet tends to the organic
selection of a modified type of denti-
tion, to a modified musculature of the
8
NATURAL HISTORY
jaws, and to modification of the diges-
tive tract, all of which organs are ex-
tremely modified in the Eskimo.
The choice, however, leads to a read-
justment of all the internal and external
reactions of man as a mechanism, to a
change in all survival values, and to a
new series of actions, reactions, and
interactions between the developing
and race-begetting man and his lifeless
and living environment, to use Osborn's
tetraplastic and tetrakinetic concep-
tions of evolution.
HOW A RACE OF TAILORS MIGHT
BE PRODUCED
The anatomy and physiology of a
tailor as studied by the British anato-
mist. Sir Arbuthnot Lane, in the year
1888, show that the lifelong habits of a
tailor engaged in his confining and
laborious trade actually produce a
distinct type of man. Such a type, if it
became heritable and thus established,
might be described humorously as a
new variety. Homo sapiens sartorius.
In the old days the tailor sat with bent
form, with crossed legs, jerking his
head sharply to the side in drawing the
needle and thread with his thumb and
forefinger through the resistant cloth —
sartorial habits which, if prolonged
through a lifetime, produce many new
characters. The type is now extinct,
for the modern tailor works only at
machines.
The following are only a few of the
modifications of muscles, tendons, and
bones produced in individuals by
hundreds of repetitions of similar
motion which might conceivably result
in the evolution of a hypothetic new
variety — Homo sapiens sartorius — in
which these modifications would be
heritable : The muscles tend to shorten
and recede into tendons; the tendons
grow relatively longer and the bony
surfaces into which they are inserted
tend to grow in the direction of the pull
which the muscles exert upon them ; the
articulation between the breastbone
(sternum) and the collarbone (clavicle),
normally a close junction, is modified
into a very complex movable joint
almost of the character of a typical
hinge joint, like that of the elbow.
Owing to the prolonged squatting
posture, which compresses the chest
and prevents the free rise and fall of the
ribs and chest breathing, the six pairs
of ribs become firmly coossified with
the respective vertebrae of the back,
indicating that they had ceased to rise
and fall with sternal breathing and
that by way of compensation respira-
tion is almost exclusively by means of
the diaphragm, which, in the normal
human being, supplements the rise and
fall of the chest. To accommodate the
side jerk of the head which the tailor
pursuing his trade for a period of
twenty or thirty years repeats thou-
sands of times, the right side of the
skull forms a new joint with the broad
transverse flange on the right side
of the first vertebra of the neck (the
atlas). This joint is adaptive; it
relieves friction between the side of the
skull and the side of the vertebra. A
small synovial cavity containing the
fluid surrounds this newly acquired
sartorial joint. This provision for
freedom of movement on the right side
of the neck is balanced by a rigid fixa-
tion on the left side of the neck be-
cause the left half of the second verte-
bra (the axis) is firmly united by bone
to the left side of the third vertebra.
Thus the second and third vertebrae
tend to form a single bone. This fixa-
tion is also adaptive, fitting the tailor
to his peculiar mode of living. But
Nature does not stop here. Doctor
Lane finds that the pegHke process (the
THE EVOLUTION OF HUMAN RACES
9
odontoid) of the axis is prolonged in its
socket of the atlas and that a new
transverse ligament is formed to keep
this peg from slipping out of place and
pressing on the spinal cord. (It is pres-
sure of the axis upon the spinal nerve
and rupture of the transverse ligament
that jiroduce instantaneous death in
hanging.) In brief, the anatomy of the
tailor is full of new anaton.iccd ch-: rac-
ier s, caused parth^ bj^ fixation of motion^
partly by exaggeration of motion.
These anatom-
ical changes, ef-
fected during the
lifetime of the in-
dividual, serve to
emphasize the
great contrast be-
tween the rapidity
of i n d i vi d u a 1
adaptation or
modification and
the slowness of
race adaptation or
evolution. All
these marvelous
adapative modi-
fications die with ,
the individual;
none of them is
inherited. The son of this tailor will
not exhibit any of these newly acquired
characters^his ribs and vertebrae will
move freeh' upon each other. It is
only through the slow process of the
coincident selection of predispositions
toward the sartorial form of body that a
new sartorial race could he produced in
which these sartorial modifications
would be inherited characters. Again,
this sartorial race, like the amphibious
or the arboreal race spoken of above,
would finall}^ emerge after the selection
of hundreds or perhaps thousands of
generations of those individuals in
which the body is peculiar^ adapted
Photograph by Herbert Lang
SQUATTING TYPE
Belgian Congo blacksmith. Observe the
feeble legs
by piodisposition to the sartorial habit.
All the evidence we have, like that of
the fossil horse, for example, shows
that modifications produced by pecul-
iar habits, if transmitted at all, would
be imperceptible in one generation.
The horse has not yet lost its lateral
fingers and toes which began to be
useless two million years ago, at the
beginning of the Oligocene period.
THE INFLUENCE OF HUMAN POS-
TURE ON THE SKELETON
In a most valu-
able essay by
Arthur Thomson
in 1889 upon 'The
Influence of Pos-
ture on the Form
of the Articular
Surfaces of the
Tibia and Astrag-
alus in the Differ-
ent Races of Man
and the Higher
Apes,' we find
clearly brought
out the distinction
between congenital
variations and
those which may
be acquired by
prolonged habits of life. It is per-
fectly clear from this investigation
that certain racial characters, such
as ' platycnemism ' or flattened tibia,
which have been considered of great im-
portance in anthropology, may prove
to be merely individual modifications
due to certain local and temporarj'-
customs. Thomson's conclusions are
that the tibia or shin is the most vari-
able in length and form of any long
bone in the body. Platycnemia, i.e.,
flattened tibia, is most frequent in
tribes living by hunting and climbing in
hillj' countries, and is associated with
the strong development of the tibialis
10
NATURAL HISTORY
posticus muscle. The great convexity
of the external condyloid surface of the
tibia in savage races appears to be
developed during life by the frequent or
habitual knee flexure in squatting ; it is
less developed where the tibia has a
backward curve and is independent of
platycnemia. Another product of the
squatting habit is a facet formed upon
the neck of the astragalus (heel-joint
bone) by the tibia. This facet is very
rare in European man; it is found in
the gorilla and orang, but rarely in the
chimpanzee. We must therefore be on
our guard to distinguish between con-
genital or hereditary skeletal characters
which are fundamental, and 'acquired'
skeletal modifications which may not
be hereditary.
Photograph by Underwood and Underwood
SWIMMING TYPE
Duke Kahonomoku, the world-famed
swimmer from Hawaii . Observe the strong
arms and strong legs
THE AMPHIBIOUS LIFE OF THE
PRIMITIVE HAWAIIANS
The early explorers were all im-
pressed with the amphibious life of the
natives of the 'Sandwich Islands' and
with their fearlessness and dexterity.
On Vancouver's second journey, in the
years 1793-4, he was accompanied by
the botanist Archibald Menzie, in
whose journal,^ February 5, 1794, we
find the following observations:
After the whole party had breakfasted we
left Honomazino in our canoes about nine in
the morning and soon after passed the western
part of the Island which is a dreary tract of the
most rugged rocks of lava scattered here and
there with some fishermen's huts. About noon
we came to a small village named Manaka
where we found our Chief Rookea's residence
and where we landed before his house at a
small gape between rugged precipices against
which the surges dashed and broke with such
violence and agitation and with such horrific
appearance, that even the idea of attempting
it chilled us with the utmost dread. We,
however, quietly submitted ourselves to
their guidance and were highly pleased to
see the extraordinary dexterity with which
they managed this landing. Having placed
their canoe in readiness before the gape they
watched attentively for a particular surge
which they knew would spend itself or be
overcome in the recoil of the preceding surges
before it could reach the rocks, and with this
surge they dashed in, landed us upon a rock
from which we scrambled up the precipice
and in an instant about 50 or 60 of the natives
at the word of command shouldered the canoe
with everything in her, and clambering up the
rugged steep, lodged her safely in a large
Canoe-House upon the brink of the precipice,
to our utmost astonishment.
In the afternoon our attention was at one
time directed to a number of young women
who stripped themselves quite naked upon
the summit of a pending cliff, and taking a
short run vaulted one after another from the
brink of it headlong into the sea, regardless
of the foamed and agitated appearance of that
element, and as it were setting its wildest
commotions at defiance, for at this time the
surf ran very high and dashed wiih furious
'See Hitchcock: Hawaii and Its Volcanoes, p. 65.
THE EVOLUTION OF HUMAN RACES
11
force iifi;aiiis1 the clifT, j'et they dexterously
disentanjiiled themselves, and clambering; up
the rook asain, repeated their leaps several
times with seeming satisfaction till they were
quite fatigued. The eliff was at least thirty
feet high and so very rugged with packed
rocks which were now and then deluged with
a boisterous surf, that to look down the
precipice was enough to intimidate any one
not accustomed to such extraordinary feats of
activity.
More recently so trustworthy an ob-
server as Frank Bullen' describes a feat
of which he was eye-witness. Half a
mile from the towering mass of Sunday
Island, exposed to the full force of the
gigantic swell of the South Pacific, a
young Kanaka sailor left the boat,
landed in a weltering whirl of rock-torn
sea, climbed the steep sides of the cliff
and seized a wild goat, the object of
his quest. In the struggle both lost
their footing and tumbled down the
cliff in a small avalanche of stones and
dust. Although badl}^ battered — not
by his swim but by the fall — the man
lashed the goat to his naked body,
ignoring its struggles, crawled out on
the rocks and dove once more into the
turmoil of breakers, returning to the
boat in triumph with the goat none the
worse for the experience.
HOW TO PRODUCE AN ARBOREAL
TYPE OF MAN
As the swimming habit will produce
through individual preference an am-
phibious type, which might be per-
fected in successive generations through
organic selection of the most apt
swimmers, so an arboreal type might be
produced. Thus Osborn observed in
1896," in first defining the principle of
organic and coincident selection:
If the human infant were brought up in the
branches of a tree as an arboreal type instead
of as a terrestrial, bipedal tj-pe, there is Uttle
doubt that some of the well-known early
iBullen, Frank T. The Cruise of the "Cachalot," pp.
299 305—307
2frans. N. Y. Acad. Sci.. March 9, 1896.
ii(l;il)t;iti()ns to arboreal luibit (such as the
turning in of the soles of the feet and the
grasping of the hands) might be retained and
cultivated; thus a profoundly different type
of man would be produced. . . . Diu-iiig the
enormously long period of time in which habits
induce ontogenic variations, it is po.ssible for
natural selection to work very slowly and
gradually upon predispositions to u.seful
correlated variations, and thus what are
primarily ontogenic variations become slowly
apparent as phylogenic variations or congenital
(^haraciters of the race. Man, i.e., Homo
sapiens, for instance, has been upon the earth
perhaps seventy thousand years; natural
selection has been slowly operating upon cer-
tain of these predispositions, but has not yet
eliminated those traces of the human arboreal
habits, nor completelj" adapted the human
frame to the upright position. This is as much
an expression of habit and ontogenic variation
as it is a constitutional character.
At the time the above passage was
written, Osborn adopted the wide-
spread current faith in the direct arbo-
real ancestry of man. Robinson's
well-known photograph of the baby
clinging to a broom handle, with its
feet turned in, had just been published,
and no fossil human skeletons were
known at the time to rebut the prevail-
ing arboreal hypothesis. Since then the
complete skeleton of the Neanderthal
man has been discovered, and the
balanced proportions of the upper and
lower limbs lend no support to the
arboreal hypothesis. The Neander-
thal man is descended from many
hundreds of thousands of generations
of walkers, not of tree climbers.
Another line of evidence against the
arboreal theory has recently come to
mind. It is that when man does take
to the trees i1 is never in the man-
ner of the chimpanzee or of the gorilla,
but in the manner of the bear, i.e., of
"shinning the tree," by embracing the
trunk with the arms and shins. No
anthropoid ape displays this power,
which is among the early instincts of
12
NATURAL HISTORY
Photograph by Herbert Lang
CLIMBING TYPE
Climbing pygmies of the Belgian Congo.
No monkey or ape climbs in this manner
every boy. The ape must rise into the
tree not by the trunk route but by the
branches. Once started, the swinging
action resembles that of a man on a
trapeze. The grasping is done with all
five fingers, including the rudimentary
thumb placed around the branch. The
thumb is not used either by the ape or
by the trapeze expert, because the hand
must instantly hook itself over the
branch. Consequently the thumb is not
developed and all arboreal mammals
are practically thumbless.
As a boy of ten the writer watched
the Spanish lads near Murcia, Spain,
climbing the date palms. They placed
a fibre girdle around the slender trunk
and, swaying backward and forward,
arose by slipping the girdle higher and
higher, turning the soles of the feet in-
ward on the outer sides of the trunk.
This method of tree climbing, with all
its variations, is purely a human
achievement. As tree climbing is
observed among the Hawaiian boys,
no girdle is used. The slender trunk
of the cocoanut palm is seized by the
hands and, where possible, the body
leans backward and the feet are placed
sole downward against the trunk.
DISTINCTION BETWEEN HUMAN
AND ANIMAL EVOLUTION
The great distinction between these
sartorial, amphibious, and arboreal
adaptations in man is that they are
relatively temporary — matters which
may endure for a few years, or at most
for a few centuries — whereas corres-
ponding adaptations in animals are
secular; they certainly extend through
enormous periods of time correspond-
ing with the great secular changes in
the earth's surface. If we could imag-
ine all mankind forced into a sartorial
or an amphibious mode of life for thou-
sands or hundreds of thousands of years,
then we should have a real parallel be-
tween human and animal evolution.
Among animals, however, we observe
a parallel to man evolving under the
' adaptive radiation' and ' organic selec-
tion' principles in the comparison
between the psychology and the
mechanical evolution of the various
races of the horse. The horse and the
elephant both resemble man in the
resourceful and intelligent selection of
habit and habitat. They are the only
mammals that rival man in seeking
food and in overcoming all natural
THE EVOLUTION OF HUMAN RACES
13
difficulties in every region of every
continent except Australia. Horses
would swarm in Australia if once they
had a footing there. The greatest
enemy of the horse, as well as of man,
has l)een insect-borne infectious
diseases. This debars the horse, as it
does the white and yellow races of
man, from the insect-laden tropics.
There is, however, one very funda-
mental difference between the mechani-
cal evolution of man and of the horse,
namely, that the latter has been mainly
a single-track adaptive evolution from
the verj^ beginning, whereas man
evolved in three phases, each of which
has left some traces in his anatomy :
(1) a quadrupedal terrestrial phase,
extremely remote.
(2) a quadrumanous arboreal phase,
still very remote.
(3) a bipedal and bimanous terres-