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 6 of 38)
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in the leaf ( !) and, as culmination, a tiny circular clear
spot in the fore wings (terminal part of the leaf) which shall
represent a worm-eaten hole, or a piercing of the dry leaf


by flying splinter, or the complete decay of a little spot due
to fungus growth ! A general and sufficient seeming of a
dead leaf, object of no bird's active interest, yes, but not a
dead leaf modelled with the fidelity of the wax-workers in
the modern natural history museums. When natural selec-
tion had got Kallima along to that highly desirable stage
when it was so like a dead leaf in general seeming that
every bird sweeping by saw it only as a brown leaf clinging
precariously to a half-stripped branch, it was natural
selection's bounden duty, in conformance with its obligations
to its makers, to stop the further modelling of Kallima and
just hold it up to its hardly won advantage. But what
happens? Kallima continues its way, specifically and ab-
surdly, dead-leafwards, until to-day it is a much too fragile
thing to be otherwise than very gingerly handled by its
rather anxious foster-parents, the neo-Darwinian selec-

An objection which was long ago pointed out, and which
has been emphasised strongly by some biologists and almost
overlooked by others, is that of the incom-
too shorfto^Tve P a ^ibility of the results concerning the age of
selection oppor- life on this earth as propounded by physicists
woTkf t0 d ltS an d astronomers with the demand made by the
theory of descent. This objection of the lack
of time for the production of the hosts of kinds of plants
and animals through the slow workings of natural selection
was brought forward against Darwin from the very begin-
ning and has never been given up. De Vries, 28 for example,
in a recent paper, refers to it as follows :

"The deductions made by Lord Kelvin and others from the
central heat of the earth, from the rate of the production of
the calcareous deposits, from the increase in the amount of
salt in the water of the seas, and from various other sources,
indicate an age for the inhabitable surface of the earth of
some millions of years only. The most probable estimates


lie between twenty and forty millions of years. The evolu-
tionists of the gradual line, however, have supposed many
thousands of millions of years to be the smallest amount
that would account for the whole range of evolution, from
the very beginning until the appearance of mankind. This
large discrepancy has always been a source of doubt and a
weapon in the hands of opponents of the evolutionary idea,
and it is especially in this country that much good work has
been done to overcome this difficulty. The theory of descent
had to be remoulded. On this point conviction has grown
in America during the last decades with increasing rapidity."
However (according to a newspaper clipping), Professor
Lankester, 28 a present-day Darwinian champion, in the
course of an interesting outline of the advance-

Eadmm a pos-
sible answerto ment of science in the past twenty-five years
the objection. w hi c h he gave at the opening meeting of the
British Association at York recently (September, 1906)
again raised the question of the age of the earth. Refer-
ring to the discovery of radium as one far exceeding in
importance all other modern scientific discoveries he said
that if the sun contained a fraction of one per cent, of radium,
this radium would account for and make good the heat that
is annually lost by the sun. "This is a tremendous fact,
upsetting all calculations of physicists as to duration in past
and future of the sun's heat and the temperature of the
earth's surface. The geologists and the biologists have long
contended that some thousand million years must have
passed during which the earth's surface has presented ap-
proximately the same conditions of temperature as at pres-
ent, in order to allow time for the evolution of living things
and the formation of aqueous deposits of the earth's crust.
The physicists," contended Professor Lankester, "notably
Professor Tait and Lord Kelvin, refused to allow more than
ten million years (which they have subsequently increased
to a hundred million, basing the estimate on the rate of


cooling of a sphere of the size and composition of the earth).
They have assumed that its material is self-cooling. But
as Huxley pointed out, mathematics will not give a true
result when applied to erroneous data. It has now, within
the last five years, become evident that the earth's material
is not self-cooling, but on the contrary self-heating, and
away go the restrictions imposed by physicists on geological
time. They are now willing to give us not merely a thou-
sand million years, but as many more as we want."

In this connection should be mentioned the position taken

by Ammon 30 and others who argue that the real effect or

Claim that se- result * natural selection is to preserve the

lection hinders tvpe at the expense of the variants, which would

rather than pro- " , ,

motes species- make it a retarder rather than accelerator of
change. species-change. Bumpus's S1 observations on,

and conclusions concerning, his storm-beaten English spar-
rows is an example of what Ammon claims must be the
real result of selection. Bumpus, in statistical studies of the
variation of two animal species introduced from Europe into
the United States, viz., the English sparrow and the peri-
winkle, Littorina littorea, shows that the eggs of the sparrow
and the periwinkles themselves are much more variable in
Bum us's b America than in their native regions, and the au-
servations on thor attributes this increased variability to their
"presumable emancipation from many of the re-
straining influences of natural selection.'' In the case of the
English sparrows, also, Bumpus believes himself able to
show on a basis of the examination of 136 birds brought
in wounded or stunned after a severe storm of snow, rain,
and sleet (Feb. i, 1898), that the sixty-four birds that
perished (seventy-two revived), "perished not through acci-
dent, but because they were physically disqualified, and that
the birds which survived, survived because they possessed
certain physical characters. These characters enabled them
to withstand the intensity of this particular phase of selective


elimination and distinguish them from their more unfortu-
nate companions." The fortunate characters were mas-
culinity, shortness of body, lightness, longer humerus, longer
femur, longer tibio-tarsus, longer sternum, greater brain
capacity. But more important for survival than favourable
variations was the fact of approach to the species type or
mode of variability. The extreme variants perished.
"The process of selective elimination is most severe with ex-
tremely variable individuals, no matter in what directions the
variations may occur. It is quite as dangerous to be con-
spicuously above a certain standard of organic excellence
as it is to be conspicuously below the standard. It is the
type that nature favours."


1 For a fairly complete bibliography, with excellent abstracts, of
all important critical discussions of Darwinism since 1895, see
L'Annee Biologique (ed. Y. Delage), 1895-1903; for good bibliog-
raphy also see Zoologischer Jahresbericht, issued annually. See
also discussions and notes in such journals as Natural Science, Bio-
logisches Centralblatt, Nature, Science, American Naturalist, etc.

2 Von Kolliker, A., "Uber die Darwin'sche Schopfungstheorie,"
Zeitsch. f. iviss. Zool, Vol. XIV, pp. 174-186, 1864.

' Korschinsky, S., "Heterogenesis und Evolution," Naturw. Wo~
chenschrift, Vol. XIV, pp. 273-278, 1899.

4 Morgan, T. H., "Evolution and Adaptation," 1903. A vigorous
anti-Darwinian argument, somewhat sophisticated in its lawyer-
like handling of Darwin's own words, but keen and trenchant in
its exposure of the weaknesses of the selection theories as species-
forming explanations. It is also a brief for de Vries's theory of
species-forming by mutation. (See chap, xi of this book.)

"See Osborn, H. F., "Biol. Lectures," Wood's Holl Lab., 1894,
pp. 79-100, for suggestive plea for the recognition of "the unknown
factors of evolution."

' The subject of variation, an absolutely fundamental one in any
consideration of the factors and mechanism of organic evolution, has
a very large literature pertaining to it which the
pers^nVariatfon. serious student of evolution must make considerable
' acquaintance with at the very outset. Of this litera-
ture the following books and papers may be suggested to serve as.


a means of introduction to the subject, not alone in its broad out-
lines, but in its extensive ramifications of relation to other evolution
problems. Some of these books and papers include extended biblio-
graphic lists sufficient to enable one to follow up the subject in any
of its special phases.

Darwin, Chas., "The Origin of Species," 1859.

Darwin, Chas., "The Variation of Animals and Plants under
Domestication" (Amer. ed.), 1868.

Wallace, A. R., "Darwinism," chaps, iii and iv, 1891.

Allen, J. A., "On the Mammals and Winter Birds of East Florida,"
Bull. Mus. Comp. Zool., II, pp. 161-450, Plates IV-VIII, 1871.

Gallon, R, "Natural Inheritance," 1889.

Bateson, W., "Materials for the Study of Variation," 1894.

Duncker, G., "Die Methode der Variationsstatistik," Archiv f.
Entwick. Mech., Vol. VIII, pp. 112-183, 1899. (Full bibliography.)

Rosa, D., "La riduzione progressiva della variabilita i suoi rap-
porti coll' esstinzione e coll' origine delle specie," 1899.

Conn, H. W., "The Method of Evolution," chap, iv, 1900.

Davenport, C. B., "A History of the Development of the Quan-
titative Study of Variation," Science, N. S., Vol. XII, pp. 864-870,

De Vries, H., "Die Mutationstheorie," Vol. I, pp. 7-150, pp.
412-648, 1901.

Ewart, J. C., "Variation; Germinal and Environmental," Trans.
Roy. Dublin Soc., Ser. II, Vol. VII, pp. 353-378, 1901.

Vernon, H. M., "Variation in Animals and Plants," 1903.

Delage, Y., "L'Heredite," pp. 283-310, pp. 826-843, 2d ed., 1903.

Davenport, C. B., "Statistical Methods in the Study of Varia-
tion," 2d ed., 1904. (Full bibliography.)

Kellogg and Bell, "Studies of Variation in Insects," Proc.
Wash. Acad. Sci., Vol. VI, pp. 203-332, 1904.

Lotsy, J. P., "Vorlesungen iiber Descendenztheorien," Vol. I,
chap, ix, 1906.

Biometrika, 1901-1906. A journal devoted chiefly to the sta-
tistical study of variation.

7 See Kellogg, "Variation in Parthenogenetic Insects," Science,
N. S., Vol. XXIV, pp, 695-699, 1906, in which it is shown that the

Cases of marked P art henogenetically produced drone honey-bees vary
variation in par- much more than do the workers which are of bi-
thenogenetic ani- sexual parentage, and that parthenogenetically pro-
mals ' duced plant-lice (Aphidids) vary as markedly as

insects of bisexual parentage. See also Warren, Proc. Roy. Soc.,
Vol. LXV, 1899, in which the variation in parthenogenetic varia-
tions of Daphriia magna is shown to be little, if any, smaller than


in sexually produced generations; also, Biometrika, Vol. I, pp. 129-
154, 1902, in which Warren shows the variation in parthenogenetic
series of the plant-louse Hyalopterus trirhodus to be as large as
the variability exhibited in sexual forms.

See also Haycraft, J. B., "The Role of Sex," Nat. Science, Vol.
VII, pp. 245-250, 342-344, 1895, in which paper is presented an ingen-
ious argument to show that sexual reproduction tends not merely not
to increase variation but to decrease it : "the convergence to the mean
is, theji, a result of sex~ual reproduction : it may be termed the role
of sex, and one indeed of no secondary order. The tendency con-
stantly to vary is a property inherent in protoplasm, yet often for
long periods of time the environment may be the same. In order
that a species may continue to live in such a constant environment,
the effects of variation must be checked. Sexual multiplication, a
conservative function, antagonises the progressive tendency of varia-

Other naturalists have also held strongly to this view of the role
of amphimixis. See Bailey, L. H., "The Plant Individual in the
Light of Evolution," address before the Biological Society of Wash-
ington, January 12, 1895, Science, N. S., Vol. I, p. 281, 1895, in which
paper the author points out the importance of a clear recognition
of the tremendous possibilities and actuality of asexual variation
in plants.

In a paper by Winslow and Rogers (Science, N. S., Vol. XXI.,
p. 486, 1905), referring to the classification of bacteria, there is the
following statement : "Since the swamping of minor differences by
sexual reproduction is absent from bacteria, every inheritable
variation is maintained, and instead of true species, we find an infi-
nite series of minutely differing but constant races. The only prac-
tical method of handling and systematising these, is to establish cer-
tain fairly distinct groups and types about which the individual
variations may be grouped."

* By using a large series of individuals, and carefully tabulating
the noted conditions of variation of one or more parts, using, pref-
erably, attributes whose variability is capable of being
matnernat i ca ^y expressed, such as dimensions, num-
of probabilities. bers f spines, or spots, etc., many students have
shown that these variations seem to occur in most
cases according to the law of probabilities, and that a curve plotted
so as to express graphically the actual conditions of variation for a
given character would be nearly identical with the curve that could
be plotted so as to express what variation would exist in the given
case if this variation occurred exactly according to the laws of
chance. This means that in a thousand individuals collected at


random and examined for variation in any character, say total
length of body, not only would there be found a larger number of
individuals of medium length than of any other length between the
two extremes, represented by the longest and shortest individuals,
but that the various lengths between the mean and the longest and
between the mean and the shortest, would be represented by groups
of individuals regularly decreasing in number as the length in-
creased or decreased on either side of the mean, but of equal number
if compared at equal amounts of difference away from the mean.

The curve expressing graphically the law of probabilities or,
better, the frequency of error, is determined by the formula for this
frequency deduced originally by Gauss at the beginning of the last
century. It would lead us too far afield to reproduce here the
mathematical proof of the formula or method of its determination,
but Vernon's excellent concrete illustration of how such a formula
could be deduced directly from a study of biologic variation
may be quoted. "Supposing," says Vernon in "Variation in Animals
and Plants," pp. II and 12, 1903, "a group of developing organisms
be taken, of which the growth can be affected in a favourable or an
unfavourable manner by their surroundings. Let us suppose that
there are twenty different agencies, each of which would produce
an equal, favourable effect on growth, and twenty which would pro-
duce just as great an effect in the opposite direction. Suppose, also,,
that each organism is subjected to only half of these forty different
agencies; then it would follow, according to the laws of chance,
that a larger number of the organisms would be acted upon by 10
favourable and 10 unfavourable agencies, than by any other com-
bination ; i.e., they would, on our hypothesis, remain absolutely
unaffected in their growth. A somewhat smaller number would be
acted upon by 11 favourable and 9 unfavourable agencies, or on the
whole, would have their growth slightly increased. A still smaller
proportion would be acted on by 12 favourable and 8 unfavourable
agencies, or would have their growth rather more increased. Finally,
the number of organisms acted on by 20 favourable and o unfa-
vourable agencies would be extraordinarily small, but in this case the
effect on growth would be extremely large. Similar relationships,
only in the reverse direction, would of course be found in those
cases in which the number of unfavourable agencies exceeded the
number of favourable. If desired, the proportional numbers of organ-
isms acted on by all the different combinations of agencies may be
readily determined by expanding the binomial ( l /t -j- J4) 20 . It
is found, for instance, that for each single time the organisms are
acted on by the whole 20 favourable agencies, they are acted on 190
times by 18 favourable and 2 unfavourable ; 15,504 times by 15


favourable and 5 unfavourable; and no less than 184,756 times by
10 favourable and 10 unfavourable. Let us consider that the organ-
isms acted on by 20 favourable and o unfavourable agencies have
their size increased 20 per cent.; those acted on by 15 favourable
and 5 unfavourable by 15 5 = 10 per cent.; and so on. If now
these percentage increments and decrements be plotted out at equal
distances on a base line, and ordinates corresponding to the theo-
retical frequencies erected from each, then by joining these ordinates
we shall obtain a curve which is practically identical in form with
the probability curve of the law of frequency of error. Thus, by a
simple arithmetical method, we obtain a series approximating more
and more closely to the probability curve, the greater the number
of times the expression ( l / 2 -\- Y-Z) is expanded. Expanded 20
times, the average error is less than .5 per cent., and for a greater
number of times it becomes rapidly smaller and smaller."

This discovery and formulation of the law of individual varia-
tion namely, that such variation occurs according to the law of
probabilities was first made by the Belgian anthro-
diBooTerOTofvari- P ol S ist ' Quetelet ("Lettres sur la theorie des Proba-
ation according bilites," Brussels, 1846), on a basis of the examina-
to the law of tion of the height and chest measurements of soldiers,
chance. j t was i ater elaborately confirmed by Francis Galton

(numerous papers and the book, "Natural Inheritance," 1870-1890),
by quantitative determinations of the height, weight, span of arms,
breathing capacity, strength of pull, strength of squeeze, swiftness
of blow, and keenness of sight in men and women. It has been
most illuminatingly discussed by Karl Pearson in "The Chances of
Death,, and other Studies in Evolution," 2 vols., 1897. Since then
the recognised necessity of a more thorough study and understand-
ing of variation, as the indispensable foundation of species-forming
has led to a large development of the statistical and mathematical
study of variation, under the name of biometry, a study largely due
to the initiative and genius of the English mathematician and natural
philosopher, Karl Pearson (numerous papers from 1894 to present).
Most of the methods and formulae for determining precise mathe-
matical expression of variation conditions have been devised by him.
These methods and formulae permit of an actual mathematical com-
parison of variation among various parts in one species (immensely
enlarging our definite knowledge of structural correlations), or
among similar or wholly different parts in various species. With
the statistical facts or data of variation thus put into precise mathe-
matical expression, these expressions may be submitted to a deal
of independent mathematical treatment; rather bewildering, it must
be confessed, to most biologists, but presented by the biometricians


as the first step toward making biology, in part, at least, an exact
science. But there is no question at all that the statistical and
quantitative study of variation, and the use of authoritatively
deduced mathematical expressions (and the graphic representation
of these by plotted frequency curves, polygons, etc.), have immensely
advanced our understanding of variation conditions, and given us
definiteness and concreteness in a fundamental field of evolution
study, where before were a mass of uncoordinated data and a haze
of loose generalising.

8 Bateson, Wm., "Materials for the Study of Variation," 1894.

10 See Kellogg and Bell, "Studies of Variation in Insects," Proc.
Wash. Acad. Sci., Vol. VI, pp. 203-332, 1904, in which are discussed

(pp. 257-273) variation conditions existing in the lady-
triviri'^ariations. ^d beetle, Hippodamia convergent. The variations
' in the number and character of the elytral pattern
(small black spots on a brown ground) noted in a thousand speci-
mens examined, were such that eighty-four "aberrations," or pat-
tern-variates, could be distinguished and described, and yet, an
intensity of scrutiny demanding the use of a lens was necessary to
distinguish properly these varying types. Such a scrutiny, needless
to say, will never be given these beetles by bird or lizard, the active
agents representing natural selection, as far as pattern is to be
tested. Nevertheless, these pattern variations, if not so completely
connected by gradatory steps, would be exactly the characters on
which several Hippodamia species would be based, for they range all
the way from no spots to eighteen spots, although twelve is the
species character of convergent.

11 Romanes discusses this subject of the indifference, or triviality,
of many specific characters at some length in chap, vii of his "Dar-
win and After Darwin," II, "Post-Darwinian Questions," "Heredity
and Utility," 1895.

12 Conn, H. W., "Method of Evolution," pp. 78-83, 1900.

1S Nageli, Carl, "Mechanisch-physiologische Theorie der Abstam-

mungslehre," 1884. Nageli, an eminent botanist, formulated many

NSgeli's seven vears a S tne following famous seven objections to

objections to spe- the natural selection theory of species-forming (pp.

cies-forming by 289-290) :

selection. j ch j^g f o i gen d e s ieben Gesichtspunkte hervor,

welche uns die Abstammung durch Zuchtwahl unannehmbar machen :
"i. Beziiglich der allgemeinen Bedeutung der Selectionstheorie
ist die unbestimmte Wirkung unbestimmter Ursachen und die dem
Zufall allzusehr iiberlassene Entscheidung durch die natiirliche
Zuchtwahl unserem naturwissenschaftlichen Bewusstsein weniger
zusagend. Ferner setzt sich die Selectionstheorie, welche ihrem


Princip gemass nur nach dem erreichten Nutzen einer Erscheinung
fragt, um dieselbe zu rechtfertigen, in Widerspruch mit der wahren
und exacten Naturforschung, welche vor allem die bewirkenden Ur-
sachen der Dinge zu erkennen sucht.

'2. Die Folgerung von der (kiinstlichen) Rassenbildung auf die
(natiirliche) Varietatenbildung, welche die Grundlage der Selec-
tionstheorie ausmacht, ist unzulassig, da beide wesentlich verschie-
den sind und namentlich sich rucksichtlich der Kreuzung ungleich
verhalten. Die Varietaten namlich vermischen sich sehr schwer mit
einanfler und nehmen kein fremdes Blut in irgend wirksamer Menge
auf, werden somit auch durch die ihnen gebotene Gelegenheit zur
Kreuzung nicht verandert; mit diesen Eigenschaften stimmen ihre
Vorkommensverhaltnisse genau iiberein.

"3. Niitzliche Veranderungen konnen erst, wenn sie eine bemerk-
bare Hohe erreicht haben und in zahlreichen Individuen vorhanden
sind, eine ausgiebige Verdrangung der Mitbewerber bewirken. Da
sie aber im Anfange durch eine lange Reihe von Generationen jeden-
falls noch sehr unbedeutend und nach der Selectionstheorie auch nur
in einer kleinen Zahl von Individuen vertreten sind, so bleibt die
Verdrangung aus und eine natiirliche Zuchtwahl kommt, da ihr der
wirksame Hebel mangelt, uberhaupt nicht zu Stande.

"4. Die Ernahrungseinfliisse, welche die Selectionstheorie voraus-
setzt, bewirken thatsachlich keine erblichen Veranderungen, und
wenn sie es thaten, so konnte eine Steigerung der begonnenen Aban-
derung nicht eintreten, weil die unvermeidliche Kreuzung eine
natiirliche Zuchtwahl unmoglich machen wiirde. Ferner lasst sich
aus den unbestimmten, in alien denkbaren Richtungen wirkenden
Ernahrungseinflussen der so stetige phylogenetische Fortschritt zu
einer complicirteren Organisation nicht erklaren. Ebenso wenig
werden durch dieselben die Erscheinungen der Anpassung verur-
sacht ; dies ergibt sich einerseits aus dem Umstande, dass Gebrauch
und Nichtgebrauch die Zu- und Abnahme der Organe bedingen, da

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 6 of 38)