Table of Contents
Part III: Convergence and the Origin
of Convergence on Human Origin
IT IS well known that the human skull
is plastic enough that it may, in the adult stage, be modified
towards a more ape-like form if the eating habits of the ape
are simulated in one way or another by man. The question bears
examination because many of the skulls of early man have undoubtedly
been deformed in the direction of the ape skull for what Portmann
(59) would have termed "historical" (as opposed
to genetic) reasons. Such deformation can occur within a single
lifetime. It is, of course, not inherited by the offspring, but
if the conditions of life persist over several generations, chances
are that a few skulls will be preserved as fossils whose configuration
might give the impression that their owners were not far removed
by descent from an ape-like sub-human ancestor, whereas, in point
of fact, no such relationship need be postulated.
D. Wallis observed years ago: (60)
of prehistoric human remains does not in itself justify the inference
of a common ancestry with the apes. We base this conclusion on
the fact . . . that practically all the changes in man's structure
traceable through prehistoric remains are the result of changes
in food and habit.
The most notable changes are found
in the skull. Briefly the story of changes is to: a higher frontal
region, increased bregmatic height, smaller superciliary ridges,
increased head width, less facial projection, decreased height
of orbits and a shifting of the transverse diameter downward
laterally, a more ovoid palate, smaller teeth, diminished relative
size of the third molar, shorter, wider and more ovoid mandible,
decrease in size of condyles, decrease in distance between condylar
and coronoid processes, and in general greater smoothness, less
prominent bony protuberances, less of the
59. Portmann, A., "Das
Ursprungsproblem," Eranos-Jahrbuch, 1947, p.19: "One
and the same piece of evidence will assume totally different
aspects according to the angle -- palaeontological or historical
-- from which we view it. We shall see it either as a link in
one of the many evolutionary series that the paleontologist seeks
to establish, or as something connected with remote historical
action. . . . Let me state clearly that for my part, I have not
the slightest doubt that the remains of early man known to us
should be judged historically."
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60. Wallis, Wilson D., "The Structure of Prehistoric Man"
in The Making of Man, edited by V. F. Calverton, Modern
Library, Random House, New York, 1931, pp.69ff.
"savageness" of appearance which characterizes the
apes. This is evolution in type, but the evolution is result
rather than cause, . . .
all of these features of the skull are intimately linked together
so that scarcely can one change without the change being reflected
in the others, some features, of course, reflecting the change
more immediately and more markedly than do others. If we suppose
that man's diet and his manner of preparing food have changed,
we have an index to most of the skull changes, provided that
the dietary change has been from uncooked or poorly cooked to
better cooked food, and from more stringent to less stringent
diet. Development of stronger muscles concerned with chewing
will bring about the type of changes which we find as we push
human history further back into the remote past.
most marked in the region in which chewing muscles function.
With tough food and large chewing muscles is associated a large
mandible with broad ramus, large condyles, heavy bony tissue.
. . . Larger teeth demand more alveolar space and there results
a more prognathous and more angular mandible. The more forward
projection of the teeth in both upper and lower alveolar regions
is in accordance with the characteristics of animals which use
the teeth for the mastication of tough food, and no doubt is
a function of vigorous mastication.
walls of the skull are flattened and forced inward as well as
downward, producing the elongation of the skull. The temporal
muscles reach far up on the skull, giving rise to a high temporal
ridge: they extend forward as well as backward, giving a more
prominent occipital region, and a more constricted forward region,
resulting on the forehead region of the skull in the elevation
of the superciliary ridges and intervening glabellar region.
Projecting brow ridges are associated with stout temporal and
masseter muscles and large canines.
region is constricted laterally and responds in a greater forward
projection, one result being that the transverse diameter of
the orbits is thrust upward outwardly, giving the horizontal
transverse diameter which characterizes the apes and which is
approximated in pre-historic men and in some contemporary dolichocephalic
(long headed) people. In young anthropoid apes, when chewing
muscles are little developed and there is little constriction
in the lateral region posterior and inferior to the orbits, the
transverse diameter of orbits is oblique as in man, being elevated
to the horizontal, when temporal muscles develop and function
more vigorously, thrusting in and upward the outer margin of
the orbits. Constriction of outer margins of orbits produces
the high orbits which we find in apes, and to a less marked degree
in prehistoric human remains.
One issue of
the Ciba Symposia was devoted to a study of Eskimo life. The
subject is particularly apropos in the present context because
these extraordinary people are often considered rather precise
"models" of paleolithic man. Writing in this issue,
Erwin Ackerknecht pointed out: (61)
and jaws of the Eskimo are very massive, possibly under the influence
of the intense chewing he has to practice, which also results
61. Ackerknecht, Erwin, Ciba
Symposia, vol.10, no.1, 1948, p.912.
of the chewing muscles. Eskimo teeth are often worn down to the
gums, like animal teeth, from excessive use.
Fig. 7 shows a characteristic Eskimo
male face, with the skull form outlined to show that the greatest
width is at the jowls and not in the temple region. The head
of Gainsborough's Blue Boy in Fig. 8 however, shows how
a refined diet tends to produce a head form of another kind with
the greatest width in the temporal region. It has been also pointed out that
the Eskimo skull occasionally shows a "keel" along
the top, which results directly from the need for a stronger
attachment or anchorage for the jaw muscles, which are used much
more extensively. This will be noted in Fig. 7, and should be
compared with the keel indicated in the skulls of three supposedly
human fossils in Fig. 9. It is very clearly marked in the case
of the gorilla skull in this illustration.
Howells pointed out: (62)
have a heavy and very powerful lower jaw, and the muscles which
shut it (which in man make a thin layer on and above the temple,
where you can feel them when you chew) are so large that they
lie thick on the top of the head, about two inches deep, practically
obscuring the heavy brow ridge over the eyes which is so prominent
on the skull, and giving rise to a bony crest in the middle merely
to separate and afford attachment to the muscles of the two sides.
In the Eskimo skull and in the gorilla
skull, there is therefore sometimes a certain parallelism, which
is in no way any indication of genetic relationship. The explanation
of the Eskimo keel is a historical (i.e., cultural) one. Again,
we quote Howells on this subject: (63)
jaw of these animals in chewing, gives rise to a terrific pressure
upwards against the face, and the brow ridges make a strong upper
border which absorbs it.
If man is subjected to uncooked food,
and forced in the absence of knives to tear it from the bone,
the developing muscles will find a way of strengthening their
anchorage along these bony ridges. Moreover, if there is not
in the diet that which will harden the bone in the earlier years
of life when such strains are first encountered, it is inevitable
that the skull will be depressed while still in a comparatively
plastic state, and the forepart of the brain case will be low
and sloping so that it lacks the high vault we tend to associate
with cultured man. Thus the massive brow ridges of Sinanthropus,
so similar to those of Pithecanthropus, are, as Ales Hrdlicka
62. Howells, William, Mankind
So Far, Doubleday, New York, 1945, p.68.
63. Ibid., p.131.
Contrast the form of this Eskimo head with the head of "Blue
Boy" in Fig. 8. This drawing is based on a photo reproduced
on the cover of Ciba Symposia (vol.10, No.1) and is quite exact
in its proportions: (A) a simplified outline; (B) an ancient
Eskimo skull, showing the keel (slightly exaggerated) on the
top and the front of the head.
This head is based on Gainsborough's painting, "Blue Boy,"
and is drawn to exact scale. It shows clearly the influence of
what may be termed a cultured diet. The wide part of the head
is at the temples. (A) Cranial outline for comparison with Eskimo
head in Fig. 7. (B) Modern European skull.
years ago, "a feature to be correlated with a powerful jaw
us assume, for the sake of argument, that early man was subsequently
forced to eat tough food, after an initial family had multiplied
and wandered apart; and that this food lacked that which would
harden the skull in its formative period of development. Then
the strengthening of the chewing and cervical muscles would go
hand in hand with building a substructure of bone to provide
the necessary anchorage in the form of crests as well as ridges
in the front, at the rear, and on the top of the skull. But the
skull itself would remain pliable enough that it would undergo
considerable distortion. The "keel" which is so noticeable
in the case of the gorilla, would naturally tend to appear in
this early man, because the muscles would pull the sides of the
skull in, under the increased tension (see Fig.10). When the
jaw was used for cracking bones, etc., the chief point of stress
would regularly occur at the chin, since the clamping action
between the teeth would normally be one-sided. This again led
to a certain degree of compensatory thickening. But unlike the
apes, man is a talking creature and makes much more use of his
tongue. There is reason to believe that the reinforcement of
man's chin takes the form of a bony ridge outwards rather than
inwards, on this account, and this gives the prominence which
is characteristic of the human jaw. The apes and other anthropoids
on the other hand have the reinforcement in the form of a ledge
which reaches inward instead. This is known as the simian shelf.
In some fossils of early man there is some evidence of a simian
shelf, and presumably this is a reinforcement in addition to
that which is normal for man's chin, by way of compensation for
the added load placed upon the structure at this point. Tugging
at flesh in the absence of satisfactory "cutlery,"
or maybe just bad table manners, possibly contributed to the
alveolar prognathism which is found in these early remains. The
increasing muscle development which rose up under the zygomatic
arch naturally forced the latter outwards and it developed a
is quite likely therefore that the functioning of the jaw mechanism
determines whether the skull will be depressed or not. The fossil
human forms then show clearly that the entire series has been
affected to a large degree by the same depressive and compressive
forces. Thus if early man were to have been utterly deprived
of culture it seems quite certain his fossil remains would have
64. Hrdlicka, Ales, Skeletal
Remains of Early Man, Smithsonian Institute, Miscellaneous
Collection 83, 1930, p.367.
(A) Gorilla, showing marked keel and wide zygomatic arch. (B)
Modern Man with high vault and widest dimension at the temples.
(C) Pithecanthropus. (D) Rhodesian Man. (E) Sinanthropus.
Skulls of a female gorilla (left), a Pithecanthropus (center),
and a modern Papuan native (right), viewed from above. The marked
formation of the supraorbital ridge and the postorbital narrowness
are evident. Such marked differences can almost certainly be
attributed to the development of powerful muscles for chewing
primitiveness, which might easily be misinterpreted as evidence
of a recent emergence from some anthropoid stock. Yet in point
of fact, it could happen that individuals might become degenerate
at any period in history and leave behind them a cemetery of
the most deceptive fossil remains.
Johnson remarked in this connection: (65)
likely that in very early times the human form possessed a high
degree of plasticity which it has since lost, and that from time
to time such exaggerations of certain racial characters, probably
brought about by an unfavourable environment, have occurred.
In the Pekin-Java branch of the human family, the exaggeration
of the ape-like traits has occurred to a very high degree: it
later took place, so it would seem, though not quite so pronouncedly
in Neanderthal Man, and has occurred again though to a far lesser
extent in the aborigines of Australia.
Some of the
low features of the Australians may, as Prof. Haddon thinks,
be due to racial senility, and thus the resemblance to Neanderthal
Man may be regarded as secondary or convergent. By a wider application
of this principle we may consider that "convergence"
has played a part in bringing about the resemblance of paleoanthropic
men to the anthropoid apes.
If this interpretation of the evidence
is correct, it follows that a return to the conditions of diet
and life which characterized prehistoric man would be followed
by a tendency to move also towards his physical type. Such a
resemblance to the ape as is borne sometimes by fossil man would
in no way relate to phylogenetic descent. In a given group, the
adult male would be more likely to resemble the ape than the
infant does (and probably more than the female does, too), yet
it could not be argued on this account that the adult was more
nearly related to the simian ancestor than the infant or the
female. Franz Boas pointed this out many years ago: (66)
bring two organically different individuals into the same environment
they may, therefore, become alike in their functional responses,
and we may gain the impression of a functional likeness of distinct
anatomical forms that is due to environment, not to heredity.
I have said previously that we do
not have unequivocal evidence that ape-like forms actually evolved
into more man-like forms, but we do have evidence of man becoming
physically more ape-like in cranial bone structure. Indeed, LeGros
Clark admitted that this very point has been urged quite seriously
and with some force: (67)
65. Johnson, Humphrey, The
Bible and the Early History of Mankind, London, 1947, p 89.
66. Boas, Franz: quoted by Ralph Linton, The Study of Man,
Appleton-Century, New York, 1936, p.26.
67. Clark, Sir Wilfrid LeGrow: quoted by Rendle Short, in The
Transactions of the Royal Victoria Institute, vol.66, 1935,
Prof. Wood Jones
has pointed out that there are some anatomical features which
make it easier to believe that the apes are descended from man
rather than man from an extinct ape.
believed that evolution never retraces its steps however. Thus,
he argued that such a retrogressive step would never occur. Perhaps,
but in structural form and therefore to an uncritical eye, man
may ''regress" part of the way, though the verb "degenerate"
would be much more appropriate. Man has done this, even in comparatively
recent times, as Robert Chambers pointed out when recounting
the eventual fate of certain poor Irish peasants around 1600
who were dispossessed of their homes under particularly harsh
of living is ascertained to have a powerful effect in modifying
the human figure in the course of generations, and this even
in its osseous structure. About 200 years ago, a number of people
were driven by a barbarous policy from the counties of Antrim
and Down in Ireland, towards the sea-coast: there they have ever
since been settled, but in unusually miserable circumstances.
And the consequence
is that they now exhibit peculiar features of the most repulsive
kind, projecting jaws with large open mouths, depressed noses,
high cheek bones, and bow legs, together with an extremely diminutive
stature. These, with an abnormal slenderness of limbs, are the
marks of a low and barbarous condition all over the world.
This is not a case of a single individual,
for we have here a whole group of people whose "primitive"
appearance resulted entirely from historical circumstance. Undoubtedly
they were as far removed from the apes, by descent, as you and
I, and were potentially as educable and as intelligent as their
contemporaries. If we add cases of isolated individuals who have
become "cast out" or lost to society and yet have survived
somehow to old age, we have the ingredients of "fossil man."
Since in the nature of the case, early man began in one spot,
presumably he must have spread under some pressure as population
multiplied. At the center, where a larger number of people would
encourage the development of higher civilization, fragments would
continually be breaking away like pioneers seeking more room
and greater freedom. The first small migrant groups would tend
to retreat further and further from the centre to the periphery
as the pressures behind increased, and as they did so they would
abandon the well-tried and more familiar accouterments of civilization
with which they began and would culturally regress, just as pioneers
almost always do at first. The higher their initial estate,
68. Chambers, Robert, Vestiges
of the Natural History of Creation, Churchill, London, 1844.
would be their last. In time, the struggle would diminish their
resources even further, wherever the band was too small or the
environment too harsh. A few sole survivors might well perish
in frightful isolation along the leading edge of the spreading
waves, as old age rendered their continuance impossible. These,
at the periphery, may be our "fossil men," descendants
of civilized human beings, not their ancestors.
Koestler rightly observed, (69) indeed, that longevity might well
degrade such individuals even more markedly, till, they were
can also play a part. As we know, the first Neanderthal representative
was reconstructed as a club-carrying brute creature with ape-like
stoop and a slouching gait. It is known now that this first specimen
was actually a diseased individual. (70) Subsequent
finds of Neanderthalers are known to have been quite erect in
posture. (71) And there are those who believe Mr.
Neanderthal could pass down the street quite unnoticed if he
were only correctly dressed, with a suitable haircut (see Fig.11).
the effects of disease, Jesse Williams in his Textbook of Anatomy
and Physiology said: (72)
types show characteristic markings that are known as stigmata
of degeneration. Common stigmata are: (1) receding forehead,
indicating incomplete development of frontal lobes of the brain;
(2) prognathism, a prominence of the maxillae; (3) the Canine
ear; (4) prominent superciliary ridges; (5) nipples placed too
high; and (6) supernumerary nipples.
Glandular disturbances can likewise
have profound effects on the anatomy. Keith (73) attributed
a tendency to strong brow ridges to
69. Koestler, Arthur, The
Ghost in the Machine, Hutchinson, London, 1967, p.167: "Prolongation
of the absolute lifespan of man might provide an opportunity
for features of the adult primate to reappear in human oldsters:
Methuselah would turn into a hairy ape."
70. The first Neanderthal specimen was evidently suffering from
chronic osteoarthritis, an ailment which forced him to adopt
a stooped posture. See C. S. Coon, The Story of Man, Knopf,
New York, 1962, p.40. Coon said his "bones were rotten with
arthritis." See also the report by A. J. E. Cave at the
15th lnternational Congress on Zoology, London, noted in Discovery,
November, 1958, p.469.
71. On Neanderthals' normal erectness, Alberto Carl Blanc and
Sergio Sergi, in Science (vol.90, supplement, 1939, p.13).
These authors reported the finding of two further skulls, with
the base of one skull "well preserved, enabling Prof. Sergi
to establish for the first time that Neanderthal man walked erect
and not with the ape-like posture with head thrust forward as
previously believed. The horizontal plane of the opening in the
skull shows that the bones of the neck were fitted perpendicular
into the opening, showing the posture to be erect as in the present
72. Williams, Jesse, Textbook on Anatomy and Physiology,
5th edition, Saunders, Philadelphia, 1935, p.49, footnote.
73. Keith, Sir Arthur: quoted by Sir John A. Thompson in The
Outline of Science, vol. 4, Putnam, New York, 1922, p.1097.
This Neanderthal skull (A) from La Chapelle-aux-Saints was in
due course reconstructed (B) for the Field Museum of Natural
History, Chicago, to show how our primitive ancestor looked.
It was reconstructed (C) by J. H. McGregor to show how "modern"
he really might have been in appearance.
a hyperactive pituitary; whereas
underdevelopment of the pituitary may account for a certain flatness
of face observed in many European nationals. (74)
behaviour may effect marked changes in the structure of the skull
and jaw. Tearing flesh from the bone in the absence of knives
tends not.only to strengthen the masseter muscles and enlarge
the zygomatic arch somewhat as a direct consequence, but also
to give a forward lean to the front teeth, both of which features
lend a more ape-like cast to the face. Indeed, we really have
little precise information on the extent to which bone structure
may be modified in the absence of a bone hardening diet during
is much room for a fresh look at the whole question of the
74. Keith, Sir Arthur, "Evolution
of Human Races in the Light of Hormone Theory," Bulletin
of the Johns Hopkins Hospital, 1922.
between form and function. Some of the time being spent rather
fruitlessly in an obsession with the establishment of lines of
evolutionary descent could perhaps be turned to better account
in a new direction. In the interest of truth, it is time that
a fresh look was taken at the whole question of the influence
of environmental facts (climatic, dietetic, barometric, and culture)
upon the structure of living organisms, especially man.
Copyright © 1988 Evelyn White. All rights
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Chapter (Part IV)
assuredly we live in an age when human wickedness finds many
ways to express itself more destructively than ever before: We
are probably not more wicked than in other ages, but our civilization
has armed us in ways that greatly enlarge our power to do damage.
It seems to me that evolutionary philosophy has encouraged violence
by its very emphasis on the idea of survival at all costs as
the supreme good, thus giving violent action a rationale which
justifies it. This model for human behaviour is drawn from an
erroneous view of animal behaviour and a false interpretation
of the supposed pattern which is believed to have led to the
upward evolution of all life.
we not be held responsible, those who know the facts, for failing
to apply to this hypothesis the kind of checks which we apply
readily enough to other hypotheses that can be much more securely
established from the supporting evidence than evolutionary theory
has ever been?
we see man's origin, so we see his destiny. Evolutionary theory
is not only bad science, as I see it, but an even worse philosophy.