When scientists speculate beyond their observations

Francis Galton died just 100 years ago and this anniversary is commemorated in today's Lancet. His theories of “racial types” and long association with the Egyptologist Flinders Petrie today leave a bitter taste. As a proto-geneticist, Galton's abiding passion was individual difference, but how he measured these differences and the theories he espoused were plainly crazy. His measurement and theorising of mental difference, which were based on a mixture of craniometry and the confidence that he could scientifically identify and classify intellectual ability across cultures and centuries were risible. It is his founding (and naming) of eugenics as a science that has made Galton such a controversial figure today. Today's collective memory of the Nazi death camps and their justification in the racist science of Germany's leading geneticists, made the word eugenics almost synonymous with evil.

What is often conveniently forgotten is the extent to which Galton's ideas were shared widely by the cultural elite of his time, which encompassed people of various political persuasions, including conservatives, liberals, and socialists. His interest in racial types, stimulated by his early expeditions to Africa and the Middle East, was of a piece with his assumption of the natural superiority of the European “races”. It made Petrie, the younger and poorer man, an ideal associate. Galton funded Petrie's Egyptian archaeology, with the instruction that he prepare photographs and papier-maché casts of the faces in the carved tomb and sarcophagus bas-reliefs. He and Petrie then classified these into racial categories—Egyptian, Hebrew, Aryan, and others—on the basis of the profiles. Galton experimented with making composite faces by merging photographs to reveal ideal types. As with his eugenicism, Galton's and Petrie's racism reads uncomfortably to modern ears.

It is just over 100 years ago that Ernst Haeckel founded the Monist League, the main object of which was to promote the idea of Eugenics with a view to achieving 'racial improvement'. The race which the Monists considered superior to all the others, in physique and intellect, was the white race; and among its most impressive manifestations, the Germanic people.

Most people have heard of or been taught the idea that the human embryo goes through (or recapitulates) various evolutionary stages, such as having gills like a fish, a tail like a monkey, etc., during the first few months that it develops in the womb. I was taught this as a Biology student. This idea (called embryonic recapitulation) was vigorously expounded by Ernst Haeckel from the late 1860s. Lacking the evidence, Haeckel set out to manufacture the data. He fraudulently changed drawings made by other scientists of human and dog embryos, to increase the resemblance between them and to hide the dissimilarities.

Haeckel’s German peers (notably, in 1874, Wilhelm His, professor of anatomy at the University of Leipzig) were aware of this fraud and extracted a modest confession from him, in which he blamed the draughtsman for blundering—without acknowledging that he himself was that draughtsman. Heckel was charged with fraud by five professors and when convicted by a university court at Jena admitted that he had altered his drawings. One writer reports his saying, "A small percent of my embryonic drawings are forgeries; those namely, for which the observed material is so incomplete or insufficient as to compel us to fill in and reconstruct the missing links by hypothesis and comparative synthesis. I should feel utterly condemned and annihilated by the admission, were it not that hundreds of the best observers and biologists lie under the same charge. The great majority of all morphological, anatomical, histological and embryological diagrams are not true to nature but are more or less doctored, schematized and reconstructed.

Recently, Michael Richardson has attempted to repeat Haeckel's work and further exposed the fraud. His team collected embryos of 39 different creatures, including marsupials from Australia, tree-frogs from Puerto Rico, snakes from France, and an alligator embryo from England. They found that the embryos of different species are very different. In fact, they are so different that the drawings made by Haeckel (of similar-looking human, rabbit, salamander, fish, chicken, etc. embryos) could not possibly have been done from real specimens.

He is quoted in the Times as saying, "This is one of the worst cases of scientific fraud. It’s shocking to find that somebody one thought was a great scientist was deliberately misleading. It makes me angry … What he [Haeckel] did was to take a human embryo and copy it, pretending that the salamander and the pig and all the others looked the same at the same stage of development. They don’t … These are fakes."

Despite the obvious fraud, Haeckel still has his defenders. He was perhaps too assertive, he was generalizing, he was basically correct just over-enthusiastic.

Haeckel and Galton both had the same grand idea. It's amazing what you can convince yourself of when a great idea grips you.