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Vol.4: Evolution or Creation?
The Human Brain:
Its Size and Its Complexity
IF INDIVIDUAL features of human anatomy
and physiology are considered separately, and are compared separately
with parallel features found in the animal world, a fairly good
case might be made out for the derivation of man by evolution
from some animal, presumably among the primates. But if the features
of man's anatomy and physiology are taken as a whole, viewed
in relation to each other and seen as an integrated unity, the
situation is rather different. Virtually every one of the anatomical
and physiological features listed in the previous chapter are
found singly in rudimentary or developed form somewhere else.
And even some of man's characteristic social and cultural forms
of behaviour are reflected, randomly distributed, among different
species also in rudimentary forms.
I am particularly anxious to make clear, however, is that no
single animal, nor any single species, exhibits these features
as a whole. Individuals and species can be found which have one
or several of these features, but not all of them. An
awareness of these facts will help us to avoid attaching importance
to differences in structure, etc., beyond what is proper in the
light of the evidence. At the same time, it will help us to see
more clearly that it really is the combination of features which
has made man such a unique creature.
the same Designer and Architect formed the animals as formed
man, it should surely not be at all surprising to find that successful
"solutions" to problems faced by all living things
are used over and over again in different contexts. And this
is precisely what we do find.
living things are chemically organized according to a single
basic pattern involving the same nucleic acids, peptides, and
amino acids, though not necessarily making the same selection.
In his contribution to the symposium published under the title
Prebiological Systems, Peter
T. Mora suggested that the amazing similarity in the biochemical
processes of living systems implies that life originated only
once. (24)There is, however, an alternative
implication: namely, that having designed a perfectly effective
biochemical process, the Creator thereafter employed it as a
basis for every living form that He created. Uniformity in this
respect would therefore just as likely be evidence of a single
Architect at work, as evidence of the evolution of a single chance
product. In the same vein it should be pointed out that all striated
muscle is also built on an almost identical pattern in all living
things. In this connection, J. D. Bernal draws the same kind
of conclusion that Mora drew: viz., that such "an ingenious
device," to use his term, (25) can surely
have been invented only once and must therefore have been inherited
by all the different phyla from the first prototype, "probably
to perform ciliary motion." As in the previous case, it
may just as well be evidence of a master design being re-employed
we look at the anatomy and physiology of man, we see plenty of
evidence of this re-employment of successful design features
already used elsewhere. The similarity of many of the vital organs
of living organisms is in no way necessarily evidence of descent.
The appearance of almost identical eye structures in the octopus
and in mammals should be sufficient demonstration of this fact.
Consequently, certain design features in one species that serve
a particular purpose may be found in another species in very
similar form, yet serving a somewhat different purpose. When
we compare man with the animals which are structurally most like
him, and are therefore presumed to be most nearly related, we
are driven by some compulsive thought process of the human mind
to arrange the structures in some kind of ascending or descending
order and to assume that this order represents degrees of relatedness.
We may tend to do this even when we do not accept the theory
of evolution. We make the assumption that a larger brain is a
later brain because we recognize that this happens as the infant
grows into the adult. We also tend to assume that anything which
looks more complex is more complex, because in most man-made
products this is the case.
so in considering the relationship between man and the primates
from which he is supposedly evolved, it may be well to look into
a critical organ (the brain) and a critical anatomical feature
24. Mora, Peter T., "The
Folly of Probability,'' in The Origin of Prebiological Systems,
edited by Sidney W. Fox, Academic Press, New York, 1965,
pg.2 of 10
25. Bernal,J. D., "Molecular Matrices for Living Systems,"
in The Origin of Prebiological Systems, ibid, p.79.
to stand erect), and see to what extent the differences are important.
And it may be said, in anticipation, that although we do not
yet know exactly why the size of the human brain is so much larger
than that of the ape brain, we have a somewhat better idea of
why man's erect posture is of such great importance. The two
combined, however, make all the difference in the world in terms
of the potential of man by contrast with that of his supposed
feeling that brain size or surface complexity is of crucial importance
in terms of intelligence or mental capacity and that man excels
in both, has plagued anthropological research for almost a hundred
years. Indeed, so compelling is this conviction that anthropologists
are guilty not infrequently of either doctoring or distorting
the evidence in order to close the gap between man and ape, by
raising the cranial capacity or brain size of potential missing
links, or reducing the cranial capacity of very early man.
will be helpful to have some basic figures, drawn from a number
of sources, which will give an overall picture of size ranges
of primate brains. Zuckerman gave the following cranial capacities: (26)
||366 + 6.5 cc.
||399 + 7.0 cc.
| Female Gorilla
|| 466 + 10.4
| Male Gorilla
|| 543 +4.3 cc.
| Pithecanthropus erectus
Australopithecines, represented by a number of supposedly separate
genera (Paranthropus, Pleisianthropus),
which were hailed
as missing links but are now believed to come a little too late
in the geological time scale as currently held, were of particular
interest to evolutionists because their cranial capacity was
believed to be between 450 and 550 cc., which, combined with
their much debated erectness of posture, seemed to fit rather
well between other primates and man.
man shows an extraordinarily wide range of cranial capacities.
There are records of capacities as low as 800 cc. in individuals
of normal size (28) though only found among idiots;
and it is commonly agreed
that man is not mentally normal with a cranial
26. Zuckerman, Solly, "An
Ape or the Ape," Journal of the Royal Anthropological
Institute, vol.81, parts 1 & 2. 1952, p.63
27. Australopithecines: J. T. Robinson, "The Origins and
Adaptive Radiation of Australopithecines," in Human Evolution,
edited by N. Korn and F. Thompson, Holt, Rinehart & Winston,
New York, 1967, p.296.
28. Ibid., p.284.
of less than 900 cc. This figure is sometimes referred to as the Cerebral
Rubicon for Homo sapiens. (29) Human dwarfs are known with brain volumes which may
not exceed 300-400 cc. These are not normal dwarfs but are known
as nanocephalic or "bird-brained" dwarfs. Their smaller
brain of course means far fewer functioning brain cells even
than in many chimpanzees, yet they are quite capable of learning
language and although usually mentally defective, their behaviour
is still quite specifically human. In referring to these individuals,
David Pilbeam remarked, "This clearly underlines the important
point that it is brain structure rather than brain size which
is so important in species-specific behaviour." (30) I think there is some reason, as we shall see, to
question whether even brain structure is important in any specific
way, though it may be that the protein composition of the brain
substance itself is species-specific.
one sees the cranial capacity of the gorilla given as 685 cc.
which comes close to the minimum for Homo sapiens (although
idiotic). It should be noted, however, that this was one single
gorilla measurement, and though the figure has been quoted many,
many times and often taken as a norm for gorillas, to my knowledge
it has never been duplicated. The use of the figure illustrates
how strong the temptation is to fill out the series from animals
to man. Weidenreich placed the gorilla's cranial capacity at
only 620 cc., and he gave the average for the whole anthropoid
group as being "only 415 cc."
we have said, brain weights among human beings vary enormously.
In giving measurements of brain size for contemporary man, it
is customary to use grams rather than cubic centimeters, but
for reasons which it is not necessary to enter into here, the
two forms of measurement in this case are virtually the same.
The average for the adult European male is about 1375 gm. whereas
the brain of Turgenev, the Russian novelist, weighed 2021 gm. It was exceeded
by that of only two others so far recorded: one was an imbecile.
Then there is the record of a labourer whose brain weighed 1925
gm. and a bricklayer, 1900 gm. The brain weight of Gambetta,
the famous French statesman, was only 1294 gm., or less than
29. Cerebral Rubicon: This
phrase was used by A. N. Whitehead, "The distinction between
man and animals is in one sense only a difference in degree.
But the extent of that degree makes all the difference. The Rubicon
has been crossed" (Modes of Thought, 1938; as quoted
by W. H. Thorpe, Animal Nature and Human Nature, Methuen,
1974, p.11). See also P. V. Tobias, "Olduvai Bed I Homine
with Special Reference to Its Cranial Capacity", Nature,
vol.202, 4 Apr., 1964, p.3.
30. Human dwarfs: David Pilbeam, The Evolution of Man, Thames
& Hudson, London, 1970, p.202.
31. Clark, W. E. LeGros, "Bones of Contention", Human
Evolution, edited by N. Korn and F. Thompson, Holt, Rinehart
& Winston, 1967, p.305. In fairness, Clark gives this figure
for a, not the gorilla.
32. Weidenreich, Franz, Apes, Giants and Men, University
of Chicago Press, 1948, p.10, 11.
A woman's brain is slightly smaller than man's, and the largest
woman's brain recorded was 1742 gm. � she was insane. Another
woman's brain of large size weighed 1580 gm., and she also was
insane. (33) It is some evidence of the unimportance
of brain size that the brain of Anatole France weighed only 1017
gm. while the brain of Bismark weighed 1807 gm.
we come to review fossil man, we meet with some surprises. While
certain of the supposedly earliest fossils fall nicely into place,
some of them do not do so. As we have seen, Pithecanthropus erectus
was given a capacity of 1026 cc. by Zuckerman but somewhat lower
(900�1000) by William Howells. (35) The same
authority gave a figure for Sinanthropus of 1150 cc. (36) This seems to be in the right kind of ascending scale.
But then Solo Man, (37) who was placed only just above Pithecanthropus
erectus in the evolutionary scale by Howells, had a cranial capacity
of 1300 cc.which is essentially modern man's. Once again the
order seems to be "satisfactory," but then something
goes wrong. For Solo Man is considered to have been contemporary
with Neanderthal Man, and Neanderthal Man had a cranial capacity
which in several specimens was in excess of 1625 cc., which is
far above modern man. (38) Two other primitive fossil skulls,
Wadjak and Boskop, had cranial capacities, respectively,
of 1550�1650 cc. and 1800 cc. which is even higher. (39)
we happen to have some cultural remains of his which are in every
way remarkable, Cromagnon Man is generally considered the high
point in the development of ancient Homo sapiens. Yet
Cromagnon had a slightly larger brain capacity than Neanderthal
1590�1660 cc.which is 15 percent larger than ours. (40)
It might be doubted therefore (if we are guided merely by cranial
capacity) whether modern man is really an advance on his ancestors.
Cromagnon could be the high point of modern Homo sapiens,
actual significance of brain size is being called into.question,
and so also is its structural form or surface complexity. Consider
these facts. Julian Huxley was satisfied that the evidence demonstrates
that a larger brain is a better learning organ than a
33. Various brain sizes: George
Dorsey, Why Behave Like Human Beings, Blue Ribbon Books,
New York, 1925, p.11. See also Franz Weidenreich, "The Human
Brain in the Light of Its Phylogenetic Development", Scientific
Monthy, vol.67, Aug., 1948, p.103-109.
pg.5 of 10
34 Bismark: Stanley Cobb, "Brain and Personality,"
American Journal of Psychiatry, vol.116, no.10, 1960,
35. Howells, William, Mankind So Far, Doubleday, New York,
1944, p.138. Throughout this section, values given by different
authorities vary, since measurements often involve certain imponderables
such as skulls distorted out of shape by the ground.
36. Sinanthropus: ibid., p.144.
37. Solo Man: ibid., p.179.
38. Neanderthal Man: ibid., p.166.
39. Wadjak and Boskop Man: ibid., p.192.
40. Cromagnon Man: Ashley Montagu, Introduction to Physical
Anthropology, Thomas, Springfield, Illinois, 1945, p.92.
one, though the learning process may take longer. (41) In a nutshell, his argument is that an absolutely
larger brain (i.e., not larger relative to the body itself)
will have a relatively as well as an absolutely larger
number of cells in its cortex. A larger number of cortical cells
makes more elaborate learning possible. The experiments upon
which Huxley based this were conducted by the German biologist,
Rensch. The data apply equally well not only to higher animals
like birds, but even to beetles. By contrast, Zeuner reported
that brain size becomes smaller with domestication, in spite
of the fact that domestication almost certainly is accompanied
by some enrichment of the environment, at least for the dogs
which were the subject of his report.
He explained this as being the result of atrophy of some senses
which become less important. Mention is made of an enriched environment
here because Rozenweig found that in rats, at least, an enriched
environment leads to cortical enlargement as well as increased
convolution. (43) Leakey, as though to confuse the
issue even further, reported the finding that some notable scientists
have smaller cranial capacity than some notable pugilists. (44) Is it possible that the pugilist's brain enlarges
in some area that has to do with his fighting capacity whereas
the scientist's brain diminishes without duly compensating for
the loss in some other area related to thinking?
it appears now that there is less certainty than previously even
about the validity of "localization theories" i.e.,
the idea that certain parts of the brain are set aside for certain
functions. Years ago, Ralph Gerard, in attempting to localize
in the brain such functions as the faculty of speech, etc., wrote:
"It remains sadly true that most of our present understanding
of mind would remain as valid and useful if, for all we know,
the cranium was stuffed with cotton wadding." (45) This was written in 1946. Similarly, R. E. D. Clark
noted that according to K. S. Lashley, no part of the upper brain
is vital, but one part may take over the functions of another
with relative ease. (46) The debate continues and even a symposium
on localization of function in the cerebral cortex held in Oxford
in 1954 came up with no altogether clear cut evidence of such
41. Huxley, Sir Julian, Evolution
in Action, Chatto & Windus, London, 1953, p.99.
42. Zeuner, F. E., "Domestication of Animals," in A
History of Technology, vol.1, edited by Charles
Singer, E. J. Holmyard and A> R. Hall, Oxford University Press,
43. Rosenzweig,Mark R., et al., "Brain Changes in
Response to Experience," Scientific American, February
44. Leakey, L. S. B., a panel on "Man as an Organism,"
Evolution After Darwin, vol.3, edited by Sol Tax and Charles
Callender, University of Chicago Press, 1960, p.168.
45. Gerard, Ralph, "The Biological Basis of Imagination,"
Scientific Monthly, June, l946, p.487.
46 Lashley, K. S.: quoted by R. E. D. Clark in Science and
Religion, vol.1, no.5, 1948, p.223.
except that language seems to be organized in the left hemisphere
in those who are congenitally right-handed, and vice versa.
Science News reported in 1966 that a man suffering from brain
cancer had his entire left cerebral hemisphere removed
and, contrary to all medical expectations, regained some ability
to speak, write, comprehend speech, and move his right limbs. (47) The report said, "The brain may have a much
greater capacity to reorganize itself than was believed."
There are neural connections between areas of the brain
and bodily functions, but if these areas are damaged or destroyed,
other areas seem to take over. One of those who took part in
the case (Dr. J. A. B. Bates) showed that even though such connections
do seem to exist, precisely the same responses are obtained by
stimulation of the white fibers of the cortico-spinal column
as by stimulation of the gray matter itself.
It was felt that the position he took on this implied a radical
break with the traditional doctrine of the hierarchical organization
of function in the central nervous system.
Irving Hallowell, in a contribution to a Darwin Centennial Symposium,
made this significant remark: (49)
as integrative functions are concerned, the present weight of
evidence appears to focus upon the influence exercised by the
masses of nerve cells in the upper part of the brain stem upon
the more recently evolved cortical areas. An older notion that
the cortex itself was of prime significance because it was somehow
"the seat of consciousness" no longer seems to make
complete neurological sense.
He then added this footnote: (50)
tradition, which seems to be largely shared by scientific men,
has taken it for granted that the cortex is a sort of essential
organ for the purposes of thinking and consciousness, and that
final integration of neural mechanisms takes place in it.
is only natural since there has been an extraordinary enlargement
of the cortex in the human brain, and, at the same time, man
seems to be endowed with intellectual functions of a new order.
the whole anterior frontal area, on one or both sides, may be
removed without loss of consciousness. During the amputation
the individual may continue to talk unaware of the fact that
he is being deprived of that area which most distinguishes his
brain from that of the chimpanzee.
47 Science News, vol.
90, December 24, 1966, p.555.
pg.7 of 10
48. Bates: referred to by 0. L. Zangwill, "Localization
in the Cerebral Cortex," Nature, October 16, 1954,
49. Hallowell, A. Irving, "Self, Society and Culture in
Phylogenetic Perspective," in Evolution After Darwin,
edited by Sol Tax and Charles Callender, University of Chicago
Press, 1960, vol.2, p.344.
50. Hallowell: quoted by W. Penfield and T. Rasmussen, The
Cerabral Cortex of Man, Macmillan, New York, 1950, pp. 204-206,
The most complete study in condensed form of which
I am aware, of the relationship between brain size, both absolute
and relative, and surface complexity was written by Weidenreich
in a paper entitled "The Human Brain in the Light of Its
Phylogenetic Development." It is difficult to summarize
such a compact statement of the facts of the case, but we shall
make an attempt. As a kind of introduction to his analysis of
the data, Weidenreich observed: (51)
ago I came across a pamphlet published in 1934, which was written
by an English physician. In the author's opinion, the only factors
that determined man's evolution since his beginnings as a primitive
primate are environment and natural selection.
But his starting
point is the premise, "Cranial capacity is a fairly accurate
measure of the mental status from the most primitive primates
to Homo sapiens."The self-confidence with which this
statement is made is typical.
Weidenreich then admitted candidly
that we do not know of any fact which proves that mere increase
in size of the brain is tantamount to an advance in mental ability.
Indeed, increase of body size is normally accompanied by an increase
in brain size, so that the elephant has a brain that weighs almost
5000 gm. and the brain of a whale may reach 10,000 gm. And yet
for all that, in proportion to the weight of the body, the
whale has a much smaller brain than man. This might seem to give
man the edge, until it is discovered that the dwarf monkeys of
South America, the marmosets, far surpass man in this respect,
having 1 gram of brain per 27 gm. of body substance, whereas
man has 1 gram of brain to 44 gm. of body substance. (52)
And man is surpassed even
more in these proportions by the capuchin monkey with one gram
of brain substance for 17.5 gm. of body substance. It is as Weidenreich
observed, (53) "Therefore, neither the absolute
nor the relative size of the brain can be used to measure the
degree of mental ability in animals or in man."
then turned to the discussion of the surface pattern of the hemispheres
and noted that primates and man do not differ from other mammalian
orders with regard to the presence and abundance of the wrinkle
lost again if we suppose that the number or complexity of the
51. Weidenreich, Franz, "The
Human Brain in the Light of Its Phylogenetic Development,"
Scientific Monthly, vol.67, August, 1948, p.103.
52. The fact is well known: see Adolph Schultz, "The Specializations
of Man and His Place Among the Catarrhine Primates," in
Cold Spring Harbor Symposia on Quantitative Biology, vol.15,
1951, p.45. Also Sir Solly Zuckerman, "Myths and Methods
in Anatomy," Journal of the Royal College of Surgeons
(Edinburgh), vol.11, no.2, 1966, p.92.
53. Weidenreich, Franz, "The human Brain in the Light of
Its Phylogenetic Development", Scientific Monthly,
vol.67, Aug., 1948, pp.104, 105.
54. Ibid., p.106.
wrinkles is co-related
with progress or perfection of mental faculties.
monkey, which many experimental psychologists regard as equal
in docility (i.e., educability) to any highly gifted chimpanzee,
possesses an almost smooth brain surface, whereas the chimpanzee
has a wrinkled one that comes close to that of man.
and its relatives, however, again steal the show. They have the
greatest number and finest wrinkles all over the hemispheres,
and the most intricate arrangement in the whole animal kingdom.
He thus concluded that all the recorded
facts indicate that neither the size nor the form of the brain,
nor the surface of the hemispheres nor their wrinkled pattern
in general or in detail, can possibly furnish a reliable clue
to the amount and degree of general or special mental qualities.
So there it is. Weidenreich said: (55)
face of all these facts, it is hard to understand why people
cannot get rid of the idea that mere size or configuration of
a special convolution or fissure must give a clue to the mental
qualities in general and to those of certain individuals in particular.
. . .
From the anatomical point of view,
it must be rather obvious, therefore, that the uniqueness of
man cannot be tied to the organ of brain, though there
is no question that it is related to his capacity of mind,
as K. A. Yonge observed: (56)
in the ability to think about thinking that man regards himself
as unique in the animal kingdom. It is not simply in his ability
to think, that he can claim uniqueness, although he is vastly
superior. Animals show their ability to associate one past experience
with another and, as a result, to arrive at some plan of action.
The rat learning his way through the maze, the chimpanzee figuring
out a means to obtain the food out of arm's reach, the dog herding
sheep. . . . This, for purposes of this Paper, is evidence of
thinking. But man can think about thinking.
Thus it is easy to confuse the brain
of man with the brain of the animal, and say that in this
respect man is merely a superior animal.
it is not possible to compare the mind of man with the
mind of the animal, for they appear to be in different categories.
Konrad Lorenz wrote: (57)
nervous system of animals is constructed differently from ours,
and the physiological processes in it are also different from
what happens in our brain. These qualitative differences are
sufficient to make us conclude that whatever subjective phenomena
may correspond to neural processes in animals must be considerably
different from what we, ourselves, experience.
55. Ibid., p.106.
56. Yonge, K. A., "Of Birds, Bats and Bees: A Study of Schizophrenic
Thought Disorders", Canadian Psychiatnc Association Journal,
vol.3, no.1, 1958, p.1.
57. Lorenz, Konrad, On Aggression, Bantam Books, New York,
In summary, then, there is no precisely
definable way in which man's brain can be considered anatomically
superior to the brains of animals below him. Neither in its size
nor in its surface complexity does its uniqueness seem to lie.
That there is a qualitative difference, however, is almost
universally agreed. But to define this qualitative difference
is in a sense an impossible task. Where is the decisive point
at which the uniqueness of any "different" thing
becomes determinate? Who can really tell?
pg.10 of 10
Copyright © 1988 Evelyn White. All rights
Previous Chapter Next
assuredly, man's mind is vastly different, no matter
how similar his brain cells may be to animal brain cells. So,
somewhere, some other factor has added a dimension which is missing
in the animal world. We can see the effects of this dimension
at once. And in a small way we can also discern some of the reasons
why this added dimension was effective in man where it almost
certainly could not have been effective in any other animal.
A certain combination of anatomical features in the design of
his body as a whole has allowed the special potential of his
mind to express itself in unique ways These features, anatomical
though they are, have effects far removed from any mere biological
advantage. They have permitted not merely the creation of a superior
technology -- for some animals build houses and construct dams,
which are forms of technology of a sort � but a whole series
of cultural phenomena: language and art, social organization
in which the individual may consciously sacrifice himself
for the good of others, philosophy and science, ceremony and
worship. . . . And above all, and most significantly of all,
these features have provided an entirely appropriate channel
for the revelation of God in Christ by incarnation in a truly
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