The Outline of Science, Vol. 1 (of 4)

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It is not clear why iron should not have been the earliest metal to be
used by man, but the Iron Age dates from about the middle of the second
millennium B.C. From Egypt the usage spread through the Mediterranean
region to North Europe, or it may have been that discoveries made in
Central Europe, so rich in iron-mines, saturated southwards, following
for instance, the route of the amber trade from the Baltic. Compared
with stone, the metals afforded much greater possibilities of
implements, instruments, and weapons, and their discovery and usage had
undoubtedly great influence on the Ascent of Man. Occasionally, however,
on his descent.

Retrospect

Looking backwards, we discern the following stages: (1) The setting
apart of a Primate stock, marked off from other mammals by a tendency to
big brains, a free hand, gregariousness, and good-humoured
talkativeness. (2) The divergence of marmosets and New World monkeys and
Old World monkeys, leaving a stock--an anthropoid stock--common to the
present-day and extinct apes and to mankind. (3) From this common stock
the Anthropoid apes diverged, far from ignoble creatures, and a humanoid
stock was set apart. (4) From the latter (we follow Sir Arthur Keith and
other authorities) there arose what may be called, without
disparagement, tentative or experimental men, indicated by
Pithecanthropus "the Erect," the Heidelberg man, the Neanderthalers,
and, best of all, the early men of the Sussex Weald--hinted at by the
Piltdown skull. It matters little whether particular items are
corroborated or disproved--e.g. whether the Heidelberg man came before
or after the Neanderthalers--the general trend of evolution remains
clear. (5) In any case, the result was the evolution of _Homo sapiens,
the man we are_--a quite different fellow from the Neanderthaler. (6)
Then arose various stocks of primitive men, proving everything and
holding fast to that which is good. There were the Palaeolithic peoples,
with rude stone implements, a strong vigorous race, but probably, in
most cases, supplanted by fresh experiments. These may have arisen as
shoots from the growing point of the old race, or as a fresh offshoot
from more generalised members at a lower level. This is the eternal
possible victory alike of aristocracy and democracy. (7) Palaeolithic men
were involved in the succession of four Great Ice Ages or
Glaciations, and it may be that the human race owes much to the
alternation of hard times and easy times--glacial and interglacial. When
the ice-fields cleared off Neolithic man had his innings. (8) And we
have closed the story, in the meantime, with the Metal Ages.

[Illustration: _After the restoration modelled by J. H. McGregor._

PILTDOWN MAN, PRECEDING NEANDERTHAL MAN, PERHAPS 100,000 TO 150,000
YEARS AGO]

[Illustration: _After the restoration modelled by J. H. McGregor._

THE NEANDERTHAL MAN OF LA CHAPELLE-AUX-SAINTS

The men of this race lived in Europe from the Third Interglacial period
through the Fourth Glacial. They disappeared somewhat suddenly, being
replaced by the Modern Man type, such as the Cromagnards. Many regard
the Neanderthal Men as a distinct species.]

It seems not unfitting that we should at this point sound another
note--that of the man of feeling. It is clear in William James's words:

Bone of our bone, and flesh of our flesh, are these half-brutish
prehistoric brothers. Girdled about with the immense darkness of
this mysterious universe even as we are, they were born and died,
suffered and struggled. Given over to fearful crime and passion,
plunged in the blackest ignorance, preyed upon by hideous and
grotesque delusions, yet steadfastly serving the profoundest of
ideals in their fixed faith that existence in any form is better
than non-existence, they ever rescued triumphantly from the jaws of
ever imminent destruction the torch of life which, thanks to them,
now lights the world for us.

Races of Mankind

Given a variable stock spreading over diverse territory, we expect to
find it splitting up into varieties which may become steadied into races
or incipient species. Thus we have races of hive-bees, "Italians,"
"Punics," and so forth; and thus there arose races of men. Certain types
suited certain areas, and periods of in-breeding tended to make the
distinctive peculiarities of each incipient race well-defined and
stable. When the original peculiarities, say, of negro and Mongol,
Australian and Caucasian, arose as brusque variations or "mutations,"
then they would have great staying power from generation to generation.
They would not be readily swamped by intercrossing or averaged off.
Peculiarities and changes of climate and surroundings, not to speak of
other change-producing factors, would provoke new departures from age to
age, and so fresh racial ventures were made. Moreover, the occurrence
of out-breeding when two races met, in peace or in war, would certainly
serve to induce fresh starts. Very important in the evolution of human
races must have been the alternating occurrence of periods of
in-breeding (endogamy), tending to stability and sameness, and periods
of out-breeding (exogamy), tending to changefulness and diversity.

Thus we may distinguish several more or less clearly defined primitive
races of mankind--notably the African, the Australian, the Mongolian,
and the Caucasian. The woolly-haired African race includes the negroes
and the very primitive bushmen. The wavy-to curly-haired Australian race
includes the Jungle Tribes of the Deccan, the Vedda of Ceylon, the
Jungle Folk or Semang, and the natives of unsettled parts of
Australia--all sometimes slumped together as "Pre-Dravidians." The
straight-haired Mongols include those of Tibet, Indo-China, China, and
Formosa, those of many oceanic islands, and of the north from Japan to
Lapland. The Caucasians include Mediterraneans, Semites, Nordics,
Afghans, Alpines, and many more.

There are very few corners of knowledge more difficult than that of the
Races of Men, the chief reason being that there has been so much
movement and migration in the course of the ages. One physical type has
mingled with another, inducing strange amalgams and novelties. If we
start with what might be called "zoological" races or strains differing,
for instance, in their hair (woolly-haired Africans, straight-haired
Mongols, curly-or wavy-haired Pre-Dravidians and Caucasians), we find
these replaced by _peoples_ who are mixtures of various races, "brethren
by civilisation more than by blood." As Professor Flinders Petrie has
said, the only meaning the term "race" now can have is that of a group
of human beings whose type has been unified by their rate of
assimilation exceeding the rate of change produced by the infiltration
of foreign elements. It is probable, however, that the progress of
precise anthropology will make it possible to distinguish the various
racial "strains" that make up any people. For the human sense of race
is so strong that it convinces us of reality even when scientific
definition is impossible. It was this the British sailor expressed in
his answer to the question "What is a Dago?" "Dagoes," he replied, "is
anything wot isn't our sort of chaps."

[Illustration: RESTORATION BY A. FORESTIER OF THE RHODESIAN MAN WHOSE
SKULL WAS DISCOVERED IN 1921

Attention may be drawn to the beetling eyebrow ridges, the projecting
upper lip, the large eye-sockets, the well-poised head, the strong
shoulders.

The squatting figure is crushing seeds with a stone, and a crusher is
lying on the rock to his right.]

[Illustration: RESTORATION BY A. FORESTIER OF THE RHODESIAN MAN WHOSE
SKULL WAS DISCOVERED IN 1921

The figure in the foreground, holding a staff, shows the erect attitude
and the straight legs. His left hand holds a flint implement.

On the left, behind the sitting figure, is seen the entrance to the
cave. This new Rhodesian cave-man may be regarded as a southern
representative of a Neanderthal race, or as an extinct type intermediate
between the Neanderthal Men and the Modern Man type.]

Steps in Human Evolution

Real men arose, we believe, by variational uplifts of considerable
magnitude which led to big and complex brains and to the power of
reasoned discourse. In some other lines of mammalian evolution there
were from time to time great advances in the size and complexity of the
brain, as is clear, for instance, in the case of horses and elephants.
The same is true of birds as compared with reptiles, and everyone
recognises the high level of excellence that has been attained by their
vocal powers. How these great cerebral advances came about we do not
know, but it has been one of the main trends of animal evolution to
improve the nervous system. Two suggestions may be made. First, the
prolongation of the period of ante-natal life, in intimate physiological
partnership with the mother, may have made it practicable to start the
higher mammal with a much better brain than in the lower orders, like
Insectivores and Rodents, and still more Marsupials, where the period
before birth (gestation) is short. Second, we know that the individual
development of the brain is profoundly influenced by the internal
secretions of certain ductless glands notably the thyroid. When this
organ is not functioning properly the child's brain development is
arrested. It may be that increased production of certain
hormones--itself, of course, to be accounted for--may have stimulated
brain development in man's remote ancestors.

Given variability along the line of better brains and given a process of
discriminate sifting which would consistently offer rewards to alertness
and foresight, to kin-sympathy and parental care, there seems no great
difficulty in imagining how Man would evolve. We must not think of an
Aristotle or a Newton except as fine results which justify all the
groaning and travailing; we must think of average men, of primitive
peoples to-day, and of our forbears long ago. We must remember how much
of man's advance is dependent on the external registration of the social
heritage, not on the slowly changing natural inheritance.

Looking backwards it is impossible, we think, to fail to recognise
progress. There is a ring of truth in the fine description AEschylus gave
of primitive men that--

first, beholding they beheld in vain, and, hearing, heard not, but,
like shapes in dreams, mixed all things wildly down the tedious
time, nor knew to build a house against the sun with wicketed sides,
nor any woodwork knew, but lived like silly ants, beneath the
ground, in hollow caves unsunned. There came to them no steadfast
sign of winter, nor of spring flower-perfumed, nor of summer full of
fruit, but blindly and lawlessly they did all things.

Contrast this picture with the position of man to-day. He has mastered
the forces of Nature and is learning to use their resources more and
more economically; he has harnessed electricity to his chariot and he
has made the ether carry his messages. He tapped supplies of material
which seemed for centuries unavailable, having learned, for instance,
how to capture and utilise the free nitrogen of the air. With his
telegraph and "wireless" he has annihilated distance, and he has added
to his navigable kingdom the depths of the sea and the heights of the
air. He has conquered one disease after another, and the young science
of heredity is showing him how to control in his domesticated animals
and cultivated plants the nature of the generations yet unborn. With all
his faults he has his ethical face set in the right direction. The main
line of movement is towards the fuller embodiment of the true, the
beautiful, and the good in healthy lives which are increasingly a
satisfaction in themselves.

[Illustration: _Photo: British Museum (Natural History)._

SIDE-VIEW OF A PREHISTORIC HUMAN SKULL DISCOVERED IN 1921 IN BROKEN HILL
CAVE, NORTHERN RHODESIA

Very striking are the prominent eyebrow ridges and the broad massive
face. The skull looks less domed than that of modern man, but its
cranial capacity is far above the lowest human limit. The teeth are
interesting in showing marked rotting or "caries," hitherto unknown in
prehistoric skulls. In all probability the Rhodesian man was an African
representative of the extinct Neanderthal species hitherto known only
from Europe.]

[Illustration: _After the restoration modelled by J. H. McGregor._

A CROMAGNON MAN OR CROMAGNARD, REPRESENTATIVE OF A STRONG ARTISTIC RACE
LIVING IN THE SOUTH OF FRANCE IN THE UPPER PLEISTOCENE, PERHAPS 25,000
YEARS AGO

They seemed to have lived for a while contemporaneously with the
Neanderthal Men, and there may have been interbreeding. Some Cromagnards
probably survive, but the race as a whole declined, and there was
repopulation of Europe from the East.]

[Illustration: _Reproduced by permission from Osborn's "Men of the Old
Stone Age."_

PHOTOGRAPH SHOWING A NARROW PASSAGE IN THE CAVERN OF FONT-DE-GAUME ON
THE BEUNE

Throughout the cavern the walls are crowded with engravings; on the left
wall, shown in the photograph, are two painted bison. In the great
gallery there may be found not less than eighty figures--bison,
reindeer, and mammoths. A specimen of the last is reproduced below.]

[Illustration: A MAMMOTH DRAWN ON THE WALL OF THE FONT-DE-GAUME CAVERN

The mammoth age was in the Middle Pleistocene, while Neanderthal Men
still flourished, probably far over 30,000 years ago.]

[Illustration: A GRAZING BISON, DELICATELY AND CAREFULLY DRAWN, ENGRAVED
ON A WALL OF THE ALTAMIRA CAVE, NORTHERN SPAIN

This was the work of a Reindeer Man or Cromagnard, in the Upper or
Post-Glacial Pleistocene, perhaps 25,000 years ago. Firelight must have
been used in making these cave drawings and engravings.]

Factors in Human Progress

Many, we believe, were the gains that rewarded the arboreal
apprenticeship of man's ancestors. Many, likewise, were the results of
leaving the trees and coming down to the solid earth--a transition which
marked the emergence of more than tentative men. What great steps
followed?

Some of the greatest were--the working out of a spoken language and of
external methods of registration; the invention of tools; the discovery
of the use of fire; the utilisation of iron and other metals; the taming
of wild animals such as dog and sheep, horses and cattle; the
cultivation of wild plants such as wheat and rice; and the irrigation of
fields. All through the ages necessity has been the mother of invention
and curiosity its father; but perhaps we miss the heart of the matter if
we forget the importance of some leisure time--wherein to observe and
think. If our earth had been so clouded that the stars were hidden from
men's eyes the whole history of our race would have been different. For
it was through his leisure-time observations of the stars that early man
discovered the regularity of the year and got his fundamental
impressions of the order of Nature--on which all his science is founded.

If we are to think clearly of the factors of human progress we must
recall the three great biological ideas--the living organism, its
environment, and its functioning. For man these mean (1) the living
creature, the outcome of parents and ancestors, a fresh expression of a
bodily and mental inheritance; (2) the surroundings, including climate
and soil, the plants and animals these allow; and (3) the activities of
all sorts, occupations and habits, all the actions and reactions between
man and his milieu. In short, we have to deal with FOLK, PLACE, WORK;
the _Famille_, _Lieu_, _Travail_ of the LePlay school.

As to FOLK, human progress depends on intrinsic racial
qualities--notably health and vigour of body, clearness and alertness of
mind, and an indispensable sociality. The most powerful factors in the
world are clear ideas in the minds of energetic men of good will. The
differences in bodily and mental health which mark races, and stocks
within a people, just as they mark individuals, are themselves traceable
back to germinal variations or mutations, and to the kind of sifting to
which the race or stock has been subjected. Easygoing conditions are not
only without stimulus to new departures, they are without the sifting
which progress demands.

As to PLACE, it is plain that different areas differ greatly in their
material resources and in the availability of these. Moreover, even when
abundant material resources are present, they will not make for much
progress unless the climate is such that they can be readily utilised.
Indeed, climate has been one of the great factors in civilisation, here
stimulating and there depressing energy, in one place favouring certain
plants and animals important to man, in another place preventing their
presence. Moreover, climate has slowly changed from age to age.

As to WORK, the form of a civilisation is in some measure dependent on
the primary occupations, whether hunting or fishing, farming or
shepherding; and on the industries of later ages which have a profound
moulding effect on the individual at least. We cannot, however, say more
than that the factors of human progress have always had these three
aspects, Folk, Place, Work, and that if progress is to continue on
stable lines it must always recognise the essential correlation of
fitter folk in body and mind: improved habits and functions, alike in
work and leisure; and bettered surroundings in the widest and deepest
sense.

BIBLIOGRAPHY

DARWIN, CHARLES, _Descent of Man_.
HADDON, A. C., _Races of Men_.
HADDON, A. C., _History of Anthropology_.
KEANE, A. H., _Man Past and Present_.
KEITH, ARTHUR, _Antiquity of Man_.
LULL, R. S., _Organic Evolution_.
MCCABE, JOSEPH, _Evolution of Civilization_.
MARETT, R. R., _Anthropology_ (Home University Library).
OSBORN, H. F., _Men of the Early Stone Age_.
SOLLAS, W. J., _Ancient Hunters and their Modern Representatives_.
TYLOR, E. B., _Anthropology and Primitive Culture_.

VI

EVOLUTION GOING ON

EVOLUTION GOING ON

Evolution, as we have seen in a previous chapter, is another word for
race-history. It means the ceaseless process of Becoming, linking
generation to generation of living creatures. The Doctrine of Evolution
states the fact that the present is the child of the past and the parent
of the future. It comes to this, that the living plants and animals we
know are descended from ancestors on the whole simpler, and these from
others likewise simpler, and so on, back and back--till we reach the
first living creatures, of which, unfortunately, we know nothing.
Evolution is a process of racial change in a definite direction, whereby
new forms arise, take root, and flourish, alongside of or in the place
of their ancestors, which were in most cases rather simpler in structure
and behaviour.

The rock-record, which cannot be wrong, though we may read it wrongly,
shows clearly that there was once a time in the history of the Earth
when the only backboned animals were Fishes. Ages passed, and there
evolved Amphibians, with fingers and toes, scrambling on to dry land.
Ages passed, and there evolved Reptiles, in bewildering profusion. There
were fish-lizards and sea-serpents, terrestrial dragons and flying
dragons, a prolific and varied stock. From the terrestrial Dinosaurs it
seems that Birds and Mammals arose. In succeeding ages there evolved all
the variety of Birds and all the variety of Mammals. Until at last arose
the Man. The question is whether similar processes of evolution are
still going on.

We are so keenly aware of rapid changes in mankind, though these
concern the social heritage much more than the flesh-and-blood natural
inheritance, that we find no difficulty in the idea that evolution is
going on in mankind. We know the contrast between modern man and
primitive man, and we are convinced that in the past, at least, progress
has been a reality. That degeneration may set in is an awful
possibility--involution rather than evolution--but even if going back
became for a time the rule, we cannot give up the hope that the race
would recover itself and begin afresh to go forward. For although there
have been retrogressions in the history of life, continued through
unthinkably long ages, and although great races, the Flying Dragons for
instance, have become utterly extinct, leaving no successors whatsoever,
we feel sure that there has been on the whole a progress towards nobler,
more masterful, more emancipated, more intelligent, and _better_ forms
of life--a progress towards what mankind at its best has always regarded
as best, i.e. affording most enduring satisfaction. So we think of
evolution going on in mankind, evolution chequered by involution, but on
the whole _progressive evolution_.

Evolutionary Prospect for Man

It is not likely that man's body will admit of _great_ change, but there
is room for some improvement, e.g. in the superfluous length of the
food-canal and the overcrowding of the teeth. It is likely, however,
that there will be constitutional changes, e.g. of prolonged
youthfulness, a higher standard of healthfulness, and a greater
resistance to disease. It is justifiable to look forward to great
improvements in intelligence and in control. The potentialities of the
human brain, as it is, are far from being utilised to the full, and new
departures of promise are of continual occurrence. What is of great
importance is that the new departures or variations which emerge in fine
children should be fostered, not nipped in the bud, by the social
environment, education included. The evolutionary prospect for man is
promising.

[Illustration: PHOTOGRAPH OF A MEDIAN SECTION THROUGH THE SHELL OF THE
PEARLY NAUTILUS

It is only the large terminal chamber that is occupied by the animal.]

[Illustration: PHOTOGRAPH OF THE ENTIRE SHELL OF THE PEARLY NAUTILUS

The headquarters of the Nautilus are in the Indian and Pacific Oceans.
They sometimes swim at the surface of the sea, but they usually creep
slowly about on the floor of comparatively shallow water.]

[Illustration: NAUTILUS

A section through the Pearly Nautilus, _Nautilus pompilius_, common from
Malay to Fiji. The shell is often about 9 inches long. The animal lives
in the last chamber only, but a tube (S) runs through the empty
chambers, perforating the partitions (SE). The bulk of the animal is
marked VM; the eye is shown at E; a hood is marked H; round the mouth
there are numerous lobes (L) bearing protrusible tentacles, some of
which are shown. When the animal is swimming near the surface the
tentacles radiate out in all directions, and it has been described as "a
shell with something like a cauliflower sticking out of it." The Pearly
Nautilus is a good example of a conservative type, for it began in the
Triassic Era. But the family of Nautiloids to which it belongs
illustrates very vividly what is meant by a dwindling race. The
Nautiloids began in the Cambrian, reached their golden age in the
Silurian, and began to decline markedly in the Carboniferous. There are
2,500 extinct or fossil species of Nautiloids, and only 4 living
to-day.]

[Illustration: _Photo: W. S. Berridge._

SHOEBILL

A bird of a savage nature, never mixing with other marsh birds.
According to Dr. Chalmers Mitchell, it shows affinities to herons,
storks, pelicans, and gannets, and is a representative of a type equal
to both herons and storks and falling between the two.]

But it is very important to realise that among plant and animals
likewise, _Evolution is going on_.

The Fountain of Change: Variability

On an ordinary big clock we do not readily see that even the minute hand
is moving, and if the clock struck only once in a hundred years we can
conceive of people arguing whether the hands did really move at all. So
it often is with the changes that go on from generation to generation in
living creatures. The flux is so slow, like the flowing of a glacier,
that some people fail to be convinced of its reality. And it must, of
course, be admitted that some kinds of living creatures, like the
Lamp-shell _Ligula_ or the Pearly Nautilus, hardly change from age to
age, whereas others, like some of the birds and butterflies, are always
giving rise to something new. The Evening Primrose among plants, and the
Fruit-fly, Drosophila, among animals, are well-known examples of
organisms which are at present in a sporting or mutating mood.

Certain dark varieties of moth, e.g. of the Peppered Moth, are taking
the place of the paler type in some parts of England, and the same is
true of some dark forms of Sugar-bird in the West Indian islands. Very
important is the piece of statistics worked out by Professor R. C.
Punnett, that "if a population contains .001 per cent of a new variety,
and if that variety has even a 5 per cent selection advantage over the
original form, the latter will almost completely disappear in less than
a hundred generations." This sort of thing has been going on all over
the world for untold ages, and the face of animate nature has
consequently changed.

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