THE APE-MEN
It is not correct to say that man is descended from any form of monkey
or ape now alive upon the globe. Both the anthropoid or man-like apes,
and men, are descended from a common ancestry, now extinct. There are
four of these man-like apes upon the earth today: the gibbon and the
orang-outang, in Asia, and the chimpanzee and the gorilla, in Africa.
But near the beginning of the Cenozoic or Recent Life Period, in that
stage known as the Oligocene, we find skeletal remains of a forerunner
of the great apes, resembling the gibbons, in the deserts of northern
Egypt. In the Miocene Stage which followed, true tree-living gibbons
found their way into Europe and continued throughout the Pliocene, the
stage preceding the Ice Age; these ranged as far north as Germany.
Another ape, quite man-like, called the _Dryopithecus_, inhabited
France in the Miocene; it was closely related to the ancestral stock
of the chimpanzee, gorilla, and orang, with a jaw remotely like the
dawn man, or Piltdown Man, found in Sussex, England. The Pliocene
saw a third great ape dwelling in Germany, and the Old Ape, or
_Paleopithecus_, inhabiting the Siwalik hills of Asia. This creature
was a generalized form apparently related to chimpanzee, gibbon and
baboon, with upper teeth resembling man’s.
The four existing man-like apes are all tree-dwellers, with long arms
especially adapted to arboreal life. In all these apes there is a
grasping power in the big toe, which is a kind of thumb; in man this
is a function of the hand alone. The opposable thumb, which may be
brought against each of the fingers, is the one characteristic lacking
in every one of the man-like apes, and which was early developed among
the ancestors of man. They had projecting faces, retreating foreheads,
and small brain-cases, compared to men; in his slow development man’s
face has become vertical, his nose prominent, his forehead high, his
brain-case large. In brain evolution, the tree life of man’s early
ancestors or cousins stimulated the development of the hind and side
portions of the brain, which control the muscular movements needed for
arboreal existence. All the man-apes have some power of walking more or
less erect on the hind limbs, thus releasing the arms. There were four
chief lines of development:
(1) the erect attitude;
(2) the opposable thumb;
(3) the growth of the front of the brain; and
(4) the acquisition of the power of speech.
In late Pliocene times the ancestor of man, in all probability a ground
ape, a running creature rather than a climbing creature, had achieved
the first three of these, and had a rudimentary power of speech. Then
came the first Glacial approach, and after thousands of years the
first Interglacial period. Scientists disagree as to whether the first
recognizable stone implements, the eoliths, came before or after the
first Glacial approach; but about this time came these first evidences
of man’s immediate ancestors upon the earth.
Among the early popularizers of the eoliths was a man named Benjamin
Harrison, a grocer, of Ightham, in Kent, England. In a great gravel
bed five to seven feet deep he found, among unmistakable paleoliths,
or chipped stones, hundreds of stones only slightly worked, with a
similarity of appearance which could hardly be accidental. In Belgium
and elsewhere many other eoliths have been found; I have picked up in
the field below my house in Hastings-on-Hudson stones of exactly the
same type. Whether these Kent or Belgium examples are the work of man
or of nature is not the most important thing; the thing to remember
is that the paleoliths or chipped stones were not originated all at
once; there must have been thousands of years of experiment before
these forms could be reached. These may not be recognizable to the
satisfaction of science; but they undoubtedly existed. Eoliths have
been found near the Sussex home of the early Piltdown man, and in
France. These are of the borer form, the hollow-scraper form, and the
crescent-shaped-scraper form. They are usually rolled and water-worn.
Nature has dulled their once keen edge, as she has dulled human
recollection of their ancient users.
Who were the man-like forms that fashioned and used these earliest
recognizable tools? Remember what was said about the infrequency
of relics of these early men. We must travel far away to find the
pre-human type which must have used similar tools.
The island of Java is separated from Asia by Sumatra and Borneo, and
by water. Geology has established that it was once a part of the
Asiatic mainland. In 1891, on the Bengawan River in central Java,
a Dutch army surgeon, Eugen Dubois, while excavating for pre-human
remains, discovered near Trinil a deposit of numerous mammal bones,
a single upper molar tooth, and, a short distance away, the top of
a skull. Further digging revealed a second molar tooth and a left
thigh bone, all imbedded and fossilized in similar fashion. In 1894
Dubois described these scattered parts as the remains of the type
of _Pithecanthropos erectus_, the erect ape-man. The _erectus_ was
determined by the thigh-bone, which demonstrated that the creature had
the same upright posture as man, and walked on two legs. The creature
was clearly not simian, or monkey; it was closer to man than to the
highest man-like ape. And yet it was not man. It was the transitional
form between man and the man-like apes, which the laws of evolution had
taught us must have once existed. It was the ancestor of man. It was
one of the missing links.
The geologists at once became busy. At first they were inclined to
place the creature in the late Mesozoic (Middle Life), also called
Tertiary (Third Stage), in the period Pliocene; but later researches
indicate that the true age is more probably Pleistocene, or the
beginning of the Ice Age, in the Cenozoic (Recent Life), also called
Quarternary (Fourth Stage). The mammal bones included a primate or
monkey called macaque; two species of the rhinoceros; and three late
Pliocene elephants,—the same elephants found in the Siwalik hills of
India, in earlier Pliocene deposits. The discovery of a race similar
to _Pithecanthropos_, the Ape-man, in India, may be anticipated.
The Trinil race may therefore be set down as late Pliocene or early
Pleistocene, as just before or during the opening of the Ice Age.
Judging from the length of the thigh bone, the Trinils were a tall
race, reaching a height of 5 feet 7 inches, a few inches higher than
the later Neanderthal race. The forehead is undeveloped, the frontal
area of the brain is small; thus the Trinil Ape-men had only a limited
faculty of profiting by experience and accumulated tradition. The
industry of the Trinil race was very elementary. The tools required
were simple, and natural flakes and fragments of flint were plentiful.
Hammer and knife were the original tools; both were picked up
ready-made, or were rudely chipped. When the edge of the flake become
dulled by use, the piece was thrown away, or the edge was retouched
for further use. If hammer or flake could not be held comfortably in
the hand, the troublesome points or edges were removed or reduced by
chipping. The stock of tools increased slowly, with the growing needs.
Artificial flakes were produced at last, to supplement the diminishing
stock of natural ones. Definite types of implements were at length
evolved, which led readily into the simplest forms of the paleoliths,
or chipped stones. It is fairly definite that the Trinil race were in
the Eolithic culture, using several weapons of wood and stone.
Periods of glaciation are periods of subsidence of the land; the
second glacial period, which came next, was by far the greatest of all
four. The glacier withdrew after many thousands of years, the land
was elevated again, and a new race appeared upon the scene. In 1907,
Schoetensack discovered in the Mauer sands near Heidelberg, Germany, a
single jaw, which has been named as belonging to the Heidelberg man.
Along with this pre-human jaw were discovered remains of the ancient
elephant, a rhinoceros, a wild horse, a primitive ox or aurochs, and
many other mammalian forms. The presence of the elephant indicates
a comparatively moist and well-forested country. The solitary jaw
indicates the human occupancy.
This Heidelberg jaw is one of the most important finds in the whole
history of anthropology. It contains features never before found in
fossil or recent man. There is no evidence of chin at all. The teeth
establish that it was not the jaw of an ape, but of a human form. The
teeth are not large, in proportion to the jaw; but the jaw is the most
powerful jaw ever known, even greater than the largest Eskimo jaw. It
indicates a skull of very massive and primitive character. The space
left for the tongue is not large; this may have interfered seriously
with the free use of the tongue for articulate speech.
The Heidelberg man is apparently a low form of the Neanderthal race,
that is, a Neanderthal in the making. The Heidelberg teeth are arranged
in a perfect arch, or horseshoe arrangement; in all the apes, the
grinding teeth are almost parallel with each other. This establishes it
as another of the missing links. We know little of the habits of this
ape-man. Future excavations may tell more of his story. All that we are
sure of is that, during the second interglacial period, this race of
subhumans roamed Europe.
Then came the third glaciation. After thousands of years, the ice
retreated, and a new race appeared upon the human stage.