Vernon L. (Vernon Lyman) Kellogg.

Darwinism to-day; a discussion of present-day scientific criticism of the Darwinian selection theories, together with a brief account of the principal other proposed auxilary and alternative theories of species-forming online

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Online LibraryVernon L. (Vernon Lyman) KelloggDarwinism to-day; a discussion of present-day scientific criticism of the Darwinian selection theories, together with a brief account of the principal other proposed auxilary and alternative theories of species-forming → online text (page 4 of 38)
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Plate's extension of his address, "Uber die Bedeutung des
Darwin'schen Selectionsprincips," made in Hamburg be-
fore the Deutsche Zoologische Gesellschaft in 1899. To
this review, as published in 1903 after being extended and
brought up to date, I beg to acknowledge a special indebted-
ness in my present attempt to get together the more im-
portant criticism, both adverse and defensive, of Darwin.
I have, however, assiduously sought out (with the help of
librarians and my indefatigable Leipzig book-dealer friend
Bernh. Liebisch), and perused the original pourings-forth of
criticism and vilification even to the reading of some matter
written by certain Roman Catholic priests with a consider-
able amateur interest in natural history and a strong pro-
fessional interest in anti-Darwinism ! But Plate has been
a guiding hand in this search for active attacks and de-

The natural selection theory as an all-sufficient explanation
of adaptation and species-forming has always had a weak-
ness at its base ; it depends absolutely, of course,
Natural selec- on the pre-existence of variations, but it itself

tion theory cased . .

on variation. has no influence whatever on the origin or con-
trol of these variations except in so far as it may
determine what individuals shall be permitted to give birth
to other individuals. Now one of the chief problems in
biology is exactly that of the origin, the causes, and the
primary control of these congenital variations.' Three
principal explanations, no one of them experimentally
proved or even fairly tested as yet, have been given of this
actually occurring congenital variation, viz., (i) that there
exists in the germ-plasm an inherent tendency or capacity
to vary so that there is inevitable variation in all individuals


produced from germ-plasm, this variation being wholly-
fortuitous and fluctuating according to some (the belief of
Darwin and his followers), or, according to others, this
variation following certain fixed or determinate lines (de-
terminate variation, orthogenetic variation, etc.) ; (2) that
amphimixis, L e., bi-parental parentage, is the principal"
cause of variation, it seeming logical to presume that indi-
vidqals produced from germ-cells derived from the fusion
of germ-plasm coming from two individuals more or less
unlike would differ slightly from either of the parental
individuals; and (3) that congenital variation is due to the
influence of the ever-varying environment of the germ-cell
producing individuals. The objections to any one of these
theories may be very pertinent, as when one says regarding
the first that calling a thing "inherent" is not clearing up in
any degree a phenomenon for which we are demanding a
causo-mechanical explanation; or of the second that it has.
been proved 7 that individuals produced parthenogenetically,
that is, from an unmated mother, vary and in some cases
vary even more than do other individuals of the same species
produced by amphimixis ; or of the third that as far as our
study of the actual processes and mechanism of the produc-
tion of germ-cells and of embryos has gone, we have found
no apparent means whereby this influence of the ambient
medium can be successfully impressed on the germ-plasm.
But however pertinent the objections to the why of varia-
tion may be they do not in any way invalidate the fact that
variations do continuously and inevitably occur in all indi-
viduals, and that while many of these variations are recog-
nisably such as have been impressed on the individual during
its personal development as immediate results of varying
temperature, amount or kind of food, degree of humidity,
etc., to which it may be exposed in its young life, others-
seem wholly inexplicable on a basis of varying individual
environment and are certainly due to some antenatal influ-


ence acting on the germ-plasm from which the embryo is

Now the natural selection theory, in its Darwinian and

neo-Darwinian form, presupposes fortuitously occurring

congenital variations of practically infinite

Darwinian, or variety in all parts of all organisms. Actual
continuous, vana- .

tion according to observation shows that all parts of all organ-

chantr^ isms do vary and that they vary congenially,
that is, independently of any immediate in-
fluence during development exercised from without by
environmental conditions, as well as in response to these
environmental influences, and finally that in many cases this
variation is fortuitous, that is, that it occurs according to
the laws 8 of chance. The industrious statistical study of
variations, including the tabulation of the variation con-
dition in long series of individuals of the same species or
race and the mathematical formulation of this variation
condition, have shown that in many specific cases, studied
in numerous kinds of animal and plant forms, the character
of the variation in any particular character may be truly
represented (with close approximation) by the mathematical
expression and curve which would exactly define the condi-
tion in which the variation would exist if it actually followed
the law of error. It is these continuous series of slight
variations, these variously called fluctuating, individual, or
Darwinian variations, occurring in all organisms at all times
and often following, in their occurrence, the laws of chance,
on which Darwin's theory of species-forming by natural
selection is based. But this same industrious statistical
and quantitative study of variation, which has proved
that some variations do occur regularly, fluctuating
around a mean or mode, has shown, as well, that in
many cases the variations distinctly tend to heap up
on one side or the other of the mean, that is, that they
tend to occur along certain lines or toward certain direc-


tions rather than uniformly out in all directions. Also it
is true, and this has of course been long known, that by
no means all variations are so slight nor in
variation"" 1 * such perfectly gradatory or continuous series
as is true of the gradatory Darwinian variations.
"Sports" have been known to breeders of plants and animals
ever since plant and animal breeding began. Bateson has
filled a large book ' with records of "discontinuous varia-
tions" in animals ; variations, that is, of large size and not
occurring as members of continuous gradatory series. So
that biologists are acquainted with many cases of variation
that seem to be of a kind, or to exhibit a tendency, to in-
stitute special directions of development, and thus not to be
of the simple, non-initiating, inert character of the fortuitous,
slight, fluctuating variations, among which natural selection
is presumed to choose those that are to become the be-
ginnings of new lines of modification and descent. Many
biologists believe firmly that variations occur in many
special cases, if not in most cases, only along certain special
lines. Palaeontologists believe, practically as a united body,
that variation has followed fixed lines through the ages;
that there has been no such unrestricted and utterly free play
of variational vagary as the Darwinian natural selection
theory presupposes.

Now it is at least obvious that natural selection is abso-
lutely limited in its work to the material furnished by varia-
tion; so that if variation occurs in any cases
Determinate on ty along certain determinate lines selection
variation as a can ^0 no more than make use of these lines.

species-forming . . .

factor. Indeed if variation can occur persistently along

determinate lines natural selection's function in
controlling evolution in such cases is limited to the police
power of restricting or inhibiting further development along
any one or more of these lines which are of a disadvan-
tageous character, that is, a character which handicaps or


destroys the efficiency of its members in the struggle for life.
The question in many men's mouths to-day is, Why may not
variation be the actual determinant factor in species-forming,
in descent? It actually is, respond many biologists and

Even Darwin believed such determinate variation to occur,
as is indicated by repeated statements in the "Origin of
Species." In chapter iv he says (to refer to but a single
one of these admissions) : "It should not, however, be over-
looked that certain rather strongly marked variations, which
no one would rank as mere individual differences, fre-
quently recur owing to a similar organisation being similarly
acted on of which fact numerous instances could be given
with our domestic productions. In such cases, if the vary-
ing individual did not actually transmit to its offspring its
newly acquired character, it would undoubtedly transmit to
them, as long as the existing conditions remain the same,
a still stronger tendency to vary in the same manner. There
can also be little doubt that the tendency to vary in the
same manner has often been so strong that all the individuals
of the same species have been similarly modified without the
aid of any form of selection. Or only a third, fifth, or
tenth part of the individuals may have been thus affected, of
which fact several instances could be given. Thus Graba
estimates that about one-fifth of the guillemots in the Faroe
Islands consist of a variety so well marked, that it was
formerly ranked as a distinct species under the name of
Uria lacrymans. In cases of this kind, if the variation were
of a beneficial nature, the original form would soon be sup-
planted by the modified form, through the survival of the

This problem of the existence or non-existence of deter-
minate variation is taken up in such detail in connection with
the explanation and discussion of various auxiliary or alter-
native theories of species-forming in later chapters of this


book that it need not detain us now. But to my mind it is

one of the most important matters in connection with the

whole great problem of descent, that is, of

Does determi- .

nate variation evolution. It is the basic problem of evolu-
exist? tion, for it is the problem of beginnings.

Selection, isolation, and the like factors are conditions
of species-forming; variation is a prerequisite, a sine
qna'non. True variation must have its causes, and these
causes are to be determined before an actual causo-me-
chanical explanation of evolution can ever be found. But
the determination of the relation of variation to species-
forming is certainly the first step now necessary in our
search for the basic factors, the real first causes of species

But even in those cases where there may exist unrestricted

indeterminate fluctuating variation in continuous series ac-

Whatdoes cording to the law of error, what is it that this

fluctuating vari- variation really offers natural selection to
ation offer selec- , ,

tion Malaria for work on? Remember what natural selection
species-forming? j s . the sav i n g o f one or te n by the actual killing
of the thousand or ten thousand because in the struggle for
existence the variations of the one or ten are of sufficient
advantage to have a life-or-death-determining value. Now
between any two successive individuals in a series arranged
on a basis of the variations in any one character of any one
organ or function, the difference is extremely slight, too
slight, one is certain, to be, in most cases, of life or death
value. But even if one's conception of the absolute inten-
sity of the rigour of the personal struggle leads to a
logical conception of an absolute advantage in any differ-
ence, however slight, in a favourable direction, it is wholly
possible that for any other characteristic equally important
in the struggle the two individuals may be in exactly reversed
position, the one possessing the infinitesimal advantage in
strength say, possessing an infinitesimal disadvantage in


sharpness of claw or in agility. What of the chances for
such a necessary coincidence in the one individual of favour-
able variations in all the ways necessary to create a real life-
or-death-determining advantage? The law of probabilities
answers that much to the dismay of the Darwinian. But,
again, why not compare the chances in the struggle of two
individuals not standing side by side in a variational series,
but at two extremes of the range ; the difference here can be
considerable, can be of positive advantage or disadvantage.
Yes, but again comes the necessity of presupposing a coin-
cidence of other advantages or at least of no coincidence of
balancing advantages and disadvantages. But even more
fatal is the condition that if an extreme variation in some one
character could be of a life-preserving advantage, yet by the
law of probabilities (and by the tale of actual observation)
those individuals standing at the extremes of the range of
variation are very, very few compared with those standing
nearer the mean, or mode, of the series, and there would
be almost a certainty of such an extreme-charactered sur-
vivor not finding a similar form with which to mate and thus
insure perpetuation of the advantage, the mating of the
individuals admittedly not depending on any necessary
similarity in variation (unless the varying characteristics
happen to be actually concerned with the mating act : see
later discussion of biological isolation, chapter ix). Con-
siderable variations, the only ones of apparent worth in a
life-and-death struggle, are in such meagre disproportion
to the less considerable that they are inevitably swamped,
extinguished, in miscellaneous cross-mating.

Let us consider a little more in detail each of the various

objections mentioned in the last few pages. Only the student

Ini ifi of systematic (classificatory) zoology or botany

of fluctuating can realise how slight and insignificant are the

various miscellaneous individual variations

which make up that basis of ever-present, myriad-faced,


fortuitous, fluctuating variability on which the whole great
structure of the selection theory is based. Yet any one's,
common sense and his intuitive comprehension of what
life-and-death value is in an animal's battle with another,,
with foreign enemies, or with inclement Nature, make
this objection of "no handle for natural selection in mis-
cellaneous slight variation" thoroughly appreciable. Polar
bearS are probably descended from brown ; and their white
fur coat is probably an advantageous adaptation in their
life in the Arctic. But did the fortuitous appearance in his-
coat of a spot of white hairs as large as a dollar or a pancake
give some ancient brown bear such an advantage in the
struggle for existence as to make him or her the fore-
runner of a new and better-adapted sort of bear? The
giraffe's long neck is very much worth while to it ; it gets
leaves from the higher branches unattainable by the short-
necked animals who find food in the same range. But did a
millimetre or even an inch of extra neck appearing as
individual variation in an ancestral short-necked giraffe
kind give natural selection a handle with which to grind out
a new species? The consideration of the usefulness of
slight variations too often leads to an argument for their
usefulness on the same grounds as sustain the belief that
the hound will never catch the hare which goes one-half as
fast as the dog. For each time the hound covers the given
stretch that lies between him and the hare at any given
moment the hare will be just one-half that distance in
advance and though the distance will get ever shorter and
shorter the hare will ever be one-half the last distance ahead.
So say the sophists. As a matter of fact the hound gets the

Spencer's example of the femur of the whale is a striking
illustration of the reality of the absurdity connected with
the argument of change on a basis of the selection of in-
finitesimal differences. The femur of the whale, says


Spencer, is evidently the atrophied rudiment of a bone once
much larger. It weighs now about one ounce, less than a
, millionth of the weight of the whole body,
ample of the Let us suppose that when it weighed two
w^ale ounces an individual had a femur which by

variational chance weighed but one ounce.
What advantage over other whales would the difference give
it? What fraction of the daily nourishment would this ad-
vantageous variation permit the fortunate whale to add to its
stored fat instead of spending it on an extra ounce of useless
femur? Who would dare claim that this variation would
aid in success in the struggle for existence ? And yet this is
the argument for the reduction of useless organs through
the influence of natural selection. Roux and Weismann,
realising the absurdity of the argument, have put forward
two theories, one called the "battle of the parts" and the
other the "theory of germinal selection" to aid the selection
theory to explain the degeneration and reduction of organs.
The reader will find these theories explained in chapter viii.
Every student of systematic zoology or botany has a keen
realisation, too, of the fact that a majority of the distinguish-
ing characters which he recognises in the vari-
Many species O us species and genera that come under his

characters of no

utility. eye are of a sort that reveal to him no trace of

particular utility or advantage. Indeed he can
go farther and express, to himself at least, his conviction
that many of these slight but constant specific differences 10
can actually have no special advantageousness about them.
One's experience as an observer of nature and one's common
sense combine to protest against that easy and sweeping
answer of the Darwinians : "shall 'poor blind man' say what
characteristic, however slight and insignificant, is or is not
of advantage in the great complex of nature?" As the
whole question after all resolves itself into one for which
"poor blind man" is attempting to find an answer satisfying


to his own understanding, however short of perfection and
omniscience that is, he is bound to answer the subsidiary
problems such as usefulness or non-usefulness on a basis of
his own seeing and understanding capacity. As a matter
of fact the indifference of many specific characteristics of
organisms is not denied by selectionists. Romanes ll was
perhaps the first representative Darwinian, after Darwin
himself, to admit this. But many biologists say, further, on
a basis of their experience as observers, that these very
indifferent, meaningless (as far as utility goes) mor-
phological characteristics and differences are much more
constant in their character than the obviously adaptive, i. e.,
useful ones. However, as pointed out first by Nageli, accord-
ing to the selection theory the characteristics of organisms
should be just in that degree the more constant, the more
useful they are. Hence there is here a serious discrepancy
between theory and fact. Darwin himself felt the force of
this objection and met it in a manner not at all acceptable
to the ultra-Darwinians, that is the strict selectionists of
post-Darwinian times. He admitted that these trivial, ap-
parently non-useful, but constant specific characters could
not be explained by natural selection, and must be due to a
fixation in the species of these characters at one time or
another through the nature of the organism and the influ-
ence of extrinsic influences ; a true Lamarckian or at least
anti-Weismannian * explanation.

This objection to the selection theory based on the ad-

* Students and readers who have not read Darwin recently, or
in the light of the controversy between the neo-Darwinians and the
neo-Lamarckians, that is, between those who disbelieve and those
who believe in the inheritance of acquired characters, will be sur-
prised to note on a careful re-reading of the "Origin of Species,"
with this post-Darwinian sharp distinction in mind, how often Dar-
win calls on the Lamarckian factors to help his species-forming
theories out of tight places. Morgan in his "Evolution and Adap-
tation" points out many cases of this.


mitted existence of indifferent species characters is well stated

by Conn 12 as follows : "But how is it with char-
Conn's state- J

mentoftheob- acters that have no utility? It is, of course, a
Smburi'on* " g reat achievement to be able to point out the
trivial charac- method by which adaptations have been pro-
duced, but if animals have some characters that
are not useful, natural selection does not explain them.
Natural selection can develop useful organs only. The real
problem which our naturalists are trying to solve is not the
origin of adaptations simply but the origin of species also.
Now while many of the characters and organs of animals
and plants are of utility to the individual there are others
that appear to be useless. As animals and plants are
studied, it is found that the different species differ from
each other by certain definite characters. These distinctive
peculiarities that distinguish species are called 'specific
characters,' and this term will be hereafter used in this
sense. The explanation of the origin of species must then
account for the origin of specific characters. Now specific
characters are frequently trivial in nature. This was long
ago recognised by Darwin, who saw that the characters by
which species are distinguished are frequently so trivial as to
be apparently useless. If, however, we are to explain the
origin of species we must find an explanation of these trivial
characters as well as the more important ones. If these
trivial characters are of no use to their possessors, then
manifestly the principle of the survival of the fittest does
not account for them. The fact that species are so com-
monly separated by characters that seem to be absolutely
useless has led some of our keenest naturalists to insist that
the survival of the fittest does not explain the origin of
species, but explains only the origin of adaptations. At all
events, it is clear that the problem of the utility of specific
characters is a very fundamental one to the discussion of the
principle of survival.


"We here come to the first parting of the ways between
scientists of different schools. On the one hand we find those
who are so thoroughly convinced of the universality of the
principle of natural selection that they insist that all specific
characters are useful, however useless they may seem. It
is beyond question that they are led to this belief in the
utility of all characters, not from observation, but simply
from their belief in the sufficiency of the law of natural
selection. They tell us that we know too little of the actual
life of organisms in nature to enable us to say that any
given character is not of use ; and to make a claim that any-
thing, no matter how trivial, is useless, is simply to confess
ignorance. We must acknowledge that many seemingly
useless organs have been found to have utility as soon as the
life habits of animals are better understood. Certainly,
utility has been found more universal than was believed to
be possible a quarter of a century ago. The followers of
Darwin have given very much attention to this matter.
They have pointed out many lines of utility hitherto not
dreamed of. They have considered great multitudes of
cases of seemingly useless characters, and by a little imagina-
tion have suggested some use to which they may be adapted.
If one reads the recent works of Wallace, the most promi-
nent advocate of this position, he will not fail to be im-
pressed with the fact that utility is much more widely
applicable as an explanation of seemingly trivial characters
than might have been thought possible. The position held
by this writer is, that inasmuch as. the law of natural
selection is a universal force which all admit, while all other
forces of evolution are yet in dispute, and inasmuch as many
seemingly useless organs have been shown to be of use, it is
perfectly legitimate to claim that when we come to under-
stand them, we shall find that all characters are of value, and
that the principle of survival of the fittest has been concerned
in the development of them all. If this is true, the survival


of the fittest explains the origin of species as well as the

Online LibraryVernon L. (Vernon Lyman) KelloggDarwinism to-day; a discussion of present-day scientific criticism of the Darwinian selection theories, together with a brief account of the principal other proposed auxilary and alternative theories of species-forming → online text (page 4 of 38)