Tuesday, February 19, 2013

An Account Of Natural Selection By A Victorian Gentleman

Who wrote this...Darwin or Wallace?

There is a law universal in nature, tending to render every reproductive being the best possible suited to its condition that its kind, or organized matter, is susceptible of, which appears intended to model the physical and mental or instinctive powers to their highest perfection and to continue them so. This law sustains the lion in his strength, the hare in her swiftness, and the fox in his wiles. As nature, in all her modifications of life, has a power of increase far beyond what is needed to supply the place of what falls by Time's decay, those individuals who possess not the requisite strength, swiftness, hardihood, or cunning, fall prematurely without reproducing—either a prey to their natural devourers, or sinking under disease, generally induced by want of nourishment, their place being occupied by the more perfect of their own kind, who are pressing on the means of subsistence . . .

There is more beauty and unity of design in this continual balancing of life to circumstance, and greater conformity to those dispositions of nature which are manifest to us, than in total destruction and new creation . . . [The] progeny of the same parents, under great differences of circumstance, might, in several generations, even become distinct species, incapable of co-reproduction.


The answer is neither.



Patrick Matthew was the author of this passage written in 1831, many years before either Charles Darwin or Alfred Wallace thought about evolution through natural selection.  Matthew wrote this in a book titled Naval Timber and Arboriculture. The link was that he managed orchards and became familiar with the principles of husbandry (and artificial selection) used in forestry and food production. His book elaborated on how to improve the timber used to build the Royal Navy's warships and in the appendix of that book he wrote about artificial selection and natural selection. Those passages and his great insight into evolution though was not appreciated at that time.

And a great passage it is! Apart from its explanation of natural selection in the first paragraph, notice the last few lines:

[The] progeny of the same parents, under great differences of circumstance, might, in several generations, even become distinct species, incapable of co-reproduction.

From the same parents under different circumstances may arise distinct species, incapable of co-reproduction.. i.e. the origin of separate lineages or branches. Several daughter species may thus branch out from a common ancestor. Darwin has been credited of having thought of this idea first. In his Notebook B in 1837 he sketched out his idea of the formation of new varieties from a common parent in a diagram which showed evolution as a branching process.. a tree of life (the only diagram in his book Origin of Species). But reading Matthew's passage I'd say he has come pretty close to stating the theory of common descent (and speciation) about 6 years before Darwin. Matthew though unlike Darwin did not extrapolate from this to draw a grander picture of the unity of all life. 

In 1860, upon reading a review of Darwin book On The Origin Of  Species in the Gardener's Chronicle,  he sent a letter to the publication pointing attention to his earlier published work. Darwin acknowledged Matthew's priority in a subsequent edition of his book.

On his part Matthew freely admitted that Darwin's achievment had greater merit:

"To me the conception of this law of Nature came intuitively as a self-evident fact, almost without an effort of concentrated thought. Mr. Darwin here seems to have more merit in the discovery than I have had; to me it did not appear a discovery. He seems to have worked it out by inductive reason, slowly and with due caution to have made his way synthetically from fact to fact onwards; while with me it was by a general glance at the scheme of Nature that I estimated this select production of species as an à priori recognisable fact—an axiom requiring only to be pointed out to be admitted by unprejudiced minds of sufficient grasp."

It was Darwin Day on February 12, so I thought I would post this interesting bit of science history.

And by the way, don't forget Alfred Wallace. This year is the centenary of his death and a repository of his work is now online.  Called Wallace Online and containing twenty nine thousand searchable pages of Wallace's writings, it is managed by John van Whye of the University of Singapore and showcases the many important contributions of Alfred Wallace to the field of biology. Van Whye also manages the website Darwin Online.

2 comments:

  1. Wonderful! Very well written by Alfred Wallace. I feel great that the language of scientific expression itself has changed a lot.
    As a young researcher, I find the idea of Natural Selection simpler than the words used to describe it (by Wallace). But anyway, the crux of this post is well received.

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  2. Prateek- thanks for those thoughts, although the passages I quoted are by Patrick Matthew, not Alfred Wallace..

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