Century
Reactions 19th to Darwin
Ignoramus, in hoc signo laboremus
We are ignorant; so let us work (Charles
Darwin)
Not one subject in the universe is unworthy
of study. (Karl Pearson)
Supporters of Darwin
Joseph
Dalton Hooker: (1817-1911): LondonBotanist,
Kew Gardens
Alfred Russell Wallace (1823-1913): Co-discoverer of
natural selection
Thomas Henry Huxley (1825-1895): London
comparative anatomy
Asa Gray (1810-1888): Harvardproposed reconciling
evolution and theology: Evolutionary Teleology
Ernst Haeckel (1834-1919): Jenaauthor of the
phylogenetic law: ontogeny recapitulates phylogeny
August Weismann (1834-1914): Freiburgrejection of
inheritance of acquired characteristics; only germ line cells
figure in procreation
Huxley: Darwin s Bulldog
I finished your book yesterday... Since I read von
Baer's Essays nine years ago no work on Natural
History
Science I have met with has made so great an
impression on me & I do most heartily thank you for the great store of
new views you have given me... As for your doctrines I am prepared to
go to the Stake if requisite... I trust you will not allow yourself to be in
any way disgusted or annoyed by the considerable abuse &
misrepresentation which unless I greatly mistake is in store for you... And
as to the curs which will bark and yelp - you must recollect that some of
your friends at any rate are endowed with an amount of combativeness
which (though you have often & justly rebuked it) may stand you in good
stead - I am sharpening up my claws and beak in readiness. (Thomas
H. Huxley to Charles Darwin, November 23, 1859)
Huxley, however, did not accept natural selection as the sole or primary
mechanism of evolution
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Wilberforce vs. Huxley
Confrontation at
British Association,
June 30, 1860
Wilberforce: Bishop
of Oxford, VP of
British Association
and Council
Member of the
Geological Society
Looks more bitter in hindsight
Supposedly Wilberforce challenged:
If anyone were willing to trace his descent through an
ape as his grandfather would he also be willing to trace
his descent similarly on the side of his grandmother?
Supposedly Huxley responded:
If there were to be an ancestor whom I should feel
shame in recalling, it would rather be a man -- a man
of restless and versatile intellect -- who, not content
with success in his own sphere of activity, plunges into
scientific questions with which he has no real
acquaintance, only to obscure them by an aimless
rhetoric, and distract the attention of his hearers from
the real point at issue by eloquent digressions and
skilled appeals to religious prejudice.
Wilberforce s published review
Darwin
did not have sufficient proof from the fossil record
for existence of any transitional forms
Practical breeders had never produced a new species by
selection
Selection could only fine tune adaptations, but could not
create anything new
In addition, he quipped that Darwin showed our
unsuspecting cousinship with the mushrooms.
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Darwin and Church of
England
Darwin
was buried in Westminster Abbey:
I think that the interment of the remains
of Mr. Darwin in Westminster Abbey is in
accordance with the judgment of the
wisest of his countrymenIt would have
been unfortunate if anything had
occurred to give weight and currency to
the foolish notion which some have
diligently propagated, but for which Mr.
Darwin was not responsible, that there is
a necessary conflict between a knowledge
of Nature and a belief in God. Bishop
of Carlisle, Harvey Goodwin, in a
memorial sermon on the Sunday
following the funeral
The Times: The Abbey needed
Darwin more than Darwin needed the
Abbey.
Darwin s Scientific Opponents
Louis
Agassiz (1807-1873): Harvard
Opposed whole idea of transmutation
As specialist in fossil fish, accepted
extinction
All forms result of creation according to
God s plan
All variants are separate species
Richard Owen (1804-1892)
Idealist morphologist (archetypes)
Accepted transmutation but not selection
Variation due to innate tendency to
deviate from the parental type
John Herschel
Son
of William Herschel, one of the discoverers
of Uranus.
Himself took up astronomy and quickly achieved
prominence
A preliminary discourse on the study of natural philosophy
(1830)major influence on Darwin
Science aims to find not just empirical laws but true
causes: causes recognized as having a real existence
in nature and not being merely hypotheses or figments
of the mind.
Objected to Darwin:
Complex adaptations cannot arise from chance variation
Labeled Darwin s theory the Law of Higgeldy-piggeldy
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William Thompson
Lord Kelvin (1824-1907): University of Glasgow
Britain s most famous physicist
Calculated heat radiation from earth s surface
Based on cooling earth theory maintained that the longest
time for earth to have been habitable is 200,000 years
Not nearly long enough for evolution by natural selection
Darwin took Thompson seriously: wrote to Wallace in 1869:
Thompson's views on the recent age of the world have
been for some time one of my sorest troubles.
His response was to ask: What could speed up the
process of evolution?
One possibility to which he appealed: inheritance of
acquired characteristics
Fleeming Jenkin
Not
a biologist: an engineer who helped
develop underwater telegraph cables and
invented supply and demand curves
Focused
on blending inheritance: if offspring are blends of
the traits of their parents, within a very few generations
variability will be eliminated.
Darwins
response was to ask: What could enhance
variability in a population?
Open to the possibility that inheritance of acquired
characteristics could enhance variability
Ernst Haeckel (1838-1919)
"I established the . . . view, that this history of the embryo
(ontogeny) must be completed by a
second, equally valuable, and closely
connected branch of thought - the
history of race (phylogeny). Both of
these branches of evolutionary science,
are, in my opinion, in the closest causal
connection; this arises from the
reciprocal action of the laws of heredity
and adaptation... 'ontogenesis is a brief and rapid
recapitulation of phylogenesis, determined by the
physiological functions of heredity (generation) and
adaptation (maintenance).'"
Haeckel, E. 1899. Riddle of the Universe at the Close
of the Nineteenth Century.
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Gastraea
All
multi-celled organisms go through
stages of becoming globular masses,
which hollows out and becomes a gastrula
with two layers: ectoderm and endoderm.
Proposed a common origin of multi-celled organisms from
a species he named Gastraea.
Mechanism for developing more complex organisms:
Compress the developmental pathway of extant
organism
Add new trait on to the end of the development
process
Jellyfish
Described
species of jellyfish in
1866 and included in Kunstformen
der Natur, Art Forms in Nature
(1902)
Named the species shown in the
center Desmonema Annasethe,
after his first wife, Anna Sethe, who
had died years earlier. He
commented that the streaming
tendrils reminded him of her flowing
blond hair.
Radiolarian
Haeckel
investigated these
tiny, single-celled
organisms in northern
Sicily after finishing his
medical degree in 1860.
They absorb silica from
the ocean and produce
highly baroque, glassy
skeletons. Different
patterns characterize
different species.
That year he also read On
the origin of species
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Haeckel to Darwin
Saw
similarities among the radiolarian
as evidence of common history
Sent his monograph 1862 Radiolaria
to Darwin
Darwin replied that the images were
the most magnificent works which I
have ever seen, & I am proud to
possess a copy from the author.
Haeckel s Representation of
Phylogeny
Developed
the idea of representing
descent relations as a tree
Haeckel vs. Ernst von Baer
Von
Baer had noted in 1828 that the embryos
of related species are extremely similarall
organisms go through stages in which they
are very similar
Subsequent development results in
species specific traits (specialization)
Development of higher life forms do
not go through the adult form of
lower life forms, but only the
embryonic form of lower life forms.
Von Baer never accepted evolution,
although Darwin utilized von Baer s
ideas
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Natural Selection and Biometrics
Whereas
many of those who embraced Darwin on the
transmutation question in the late 19th century rejected or
were dubious as to whether natural selection was the
vehicle of the generation of new species,
It was so embraced by a group of investigators who
came to be called Biometricians
They especially emphasized the gradualness of
evolution
Key to natural selection is the existence of variation on
which selection can occur
The biometricians developed the statistical tools for
characterizing the variability in traits that provided the
raw material for selection
Galton and the Development of
Biometrics
Francis
Galton, like his cousin Charles Darwin, was sent off
to study medicine, but after his father died in 1844 he was
left with a sufficient fortune to make me independent of
the medical profession.
Like Darwin, he choose to travel, traveling up the Nile to
Khartoum, and then, in 1849, set out for south west Africa,
exploring Damaraland, and writing Tropical South Africa on
his return
After the Origin, Galton turned his attention to intelligence,
its variability and its heritability.
Regression to the Mean
Studies with peas:
Diameter of Parent Mean Diameter of
Larger peas give rise
Peas (100 of each) Offspring Peas
to larger offspring, but
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17.26
very large peas do not
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17.07
give rise to ones as large
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16.37
18
16.40
as themselves
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16.13
Likewise with smaller
16
16.17
peas
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15.98
Reversion to the mean
Very interested in the heritability of traits by humans
height, weight, visual acuity, "talent and character
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Galton s studies
of height
Compared the mean
height of parents in 205
families (calculated by
multiplying the mother's
height by 1.08 and
averaging that and her
husband's height) with
the height of 928 adult
children (multiplying
daughters' heights by
1.08 again).
Graphed the results
comparing expected
value (mid-parents) and
actual (children)
Galton and Eugenics
"Eugenics
is the study of agencies under social control that
may improve or impair the racial qualities of future
generations, whether physically or mentally."
Eugenics Program
The feeble nations of the world are necessarily giving way before the
nobler varieties of mankind; and even the best of these, so far as we
know them, seem unequal to their work. The average culture of
mankind is become so much higher than it was, and the branches of
knowledge and history so various and extended, that few are capable
even of comprehending the exigencies of our modern civilization;
much less of fulfilling them. We are living in a sort of intellectual
anarchy, for the want of master minds. The general intellectual
capacity of our leaders requires to be raised, and also to be
differentiated. We want abler commanders, statesmen, thinkers,
inventors, and artists. The natural qualifications of our race are no
greater than they used to be in semi-barbarous times, though the
conditions amid which we are born are vastly more complex than of
old. The foremost minds of the present day seem to stagger and halt
under an intellectual load too heavy for their powers.
Hereditary Character and Talent (MacMillan's Magazine, 1864-5
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Raphael Weldon
. . . the questions raised by the Darwinian
hypothesis are purely statistical, and the
statistical method is the only one at present
obvious by which that hypothesis can be experimentally
checked.
Some remarks on variation in plants and animals, 1894
In
1890 study of shrimp, measured traits
such as length of various parts
First demonstration that the traits
in a wild population were distributed
normally
Controversy Brewing
William
Bateson was highly critical of a paper Weldon
submitted to the Royal Society
Weldon wrote to Pearson:
the contention 'that numbers mean nothing and do not
exist in Nature' is a very serious thing, which will have
to be fought. Most other people have got beyond it, but
most biologists have not. Do you think it would be too
hopelessly expensive to start a journal of some kind?
Weldon and Pearson then together created Biometrika
Biometrika
Biometrika
will include (a) memoirs on variation,
inheritance, and selection in animals and plants,
based upon the examination of statistically large numbers
of specimens (this will of course include statistical
investigations of anthropometry); (b) those developments
of statistical theory which are applicable to biological
problems; (c) numerical tables and graphical solutions
tending to reduce the labour of statistical arithmetic; (d)
abstracts of memoirs, dealing with these subjects, which
are published elsewhere; and (e) notes on current
biometric work and unsolved problems.
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Karl Pearson
Pearson
reported that the first thing he could remember
was sitting in a high chair sucking his thumb. Someone told
him to stop sucking it, and added that unless he did so, the
thumb would wither away. He put his two thumbs together
and looked at them for a long time. They look alike to
me, he said to himself. I can t see that the thumb I suck
is any smaller than the other. I wonder if she could be
lying to me.
Pearson
It was Galton who first freed me from the prejudice that sound
mathematics could only be applied to natural phenomena under
the category of causation. Here for the first time was a
possibility - I will not say a certainty - of reaching knowledge as
valid as physical knowledge was thought to be, in the field of
living forms and above all in the field of human conduct.
Met Weldon when Weldon was appointed to University College,
London in 1890
Weldon pressed him on mathematics:
How does one describe asymmetrical, double-humped,
and other non-Gaussian frequency distributions?
How does one derive best values for the parameters of
such distributions?
What are the probable errors of such estimates?
What is the effect of selection on one or more of the
correlated variables?
Pearson and Statistics
Accepted
view (from Adolphe Quetelet) that all
distributions could be represented as normal
Pearson investigated skewed distributions and
developed curves for asymmetric distributions
True variability different than chance variation among
errors
Coined the term standard deviation
Developed the 2 test for goodness of fit between
curve and actual distribution
Developed tools for analyzing correlations both in actual
populations () and in samples (r)
And for testing the significance of correlations in
samples
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Pearson and Eugenics
Welfare
of the nation required high pitch of internal
efficiency" achieved by "insuring that its numbers are
substantially recruited from the better stocks.
After Galton s death, Pearson named the first Galton
Professor of Eugenics
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