Embryology and Evolution

Abstract

I HAVE read with interest Mr. Purser's thoughtful letter on the subject of my review. If he will substitute the term “race-memory” for “gene”, we shall not be far apart. But the gene of the Mendelian stands out as something that is never functional. “No one”, said the late Sir Archdall Reid, “ever heard of a useful gene.” When one takes into consideration the fact that the Mendelian genes in Drosophila have been shown to increase in their damaging effect on the viability of the organism in proportion to the structural change which they involve, and when further it is discovered that genes can be artificially produced by irradiating insect eggs with X-rays—a process which kills most of the eggs—one is driven to the conclusion that a gene is germ damage of which the outward manifestation is a mutation. The only effect that natural selection would have on such aberrations would be to wipe them out. In my opinion, mutations and adaptations have nothing to do with one another and only adaptations are recapitulated in ontogeny.