"An important scientific innovation rarely makes its way by gradually winning over and converting its opponents . . . what does happen is that its opponents gradually die out."
Facing me on a shelf was a new printing in paperback of the late Arthur Koestler's pernicious and charming 1971 book, The Case of the Midwife Toad. This controversial work was Koestler's attempt to rehabilitate the reputation of the Austrian biologist Paul Kammerer, and to reeducate the public on his own and Kammerer's somewhat idiosyncratic views about the merits of long-discarded Lamarckian theories of inheritance. The persistent success of Koestler's book amply demonstrates that there does continue to be a market for these strange notions.
Kammerer began his scientific career at the turn of the century, in a time when Gregor Mendel's laws of inheritance had just been rediscovered. These laws were then being widely applied and made understandable to scientists and laymen alike. In the two decades after 1900, the actual mechanical basis of these laws of inheritance was also being uncovered: namely, that the nucleus of the cell carried the hereditary characteristics of the organism in its chromosomes, and that Mendel's rules of inheritance could be understood by the way in which parentally-derived chromosomes sorted themselves out in the egg, sperm, and developing embryo. Two of the greatest names in MBL science, Edmund Beecher Wilson and Thomas Hunt Morgan, were intimately associated with these discoveries.
The new theories of inheritance had initial difficulty in explaining the nature of those apparently random large and small variations that we now call mutations. Indeed, earlier on, a weakness of Charles Darwin's theory of evolution by natural selection had been his inability to account for the cause and nature of "variations." We currently know, of
course, that mutations involve relatively stable changes or rearrangements within the information-carrying molecules of the chromosomes, and that these changes are inherited by the usual Mendelian rules. Another, earlier view of inheritance, usually ascribed to Jean Baptiste Lamarck but supported powerfully by common folklore, considered that characters or features acquired by the organism during its lifetime, essentially by use or disuse of structures in interaction with its surroundings, might in some cases be inherited by its offspring. Yet in spite of apocryphal tales of such inheritance, there were no carefully controlled experimental results in support of such ideas. A millenium of circumcision rites by the Semitic races had certainly failed, for example, to result in the birth of males without foreskins.
PAUL KAMMERER started his scientific career when these matters of Lamarckian inheritance were still unresolved and controversial. He was a brilliant man of quite mercurial temperament in affairs of both the mind and heart. An intimate friend and companion to many of the Viennese artists, musicians, and other creative intellectuals (including composer Gustav Mahler and conductor Bruno Walter), Kammerer himself was a writer of songs and a respected music critic. It was natural that he chose to do science with a fiair to match the excitement and glitter of his cultural environment in pre-World War I Vienna. One might well have wondered, nonetheless, how Kammerer, given the bewildering multitude of his passions and hobbies (particularly women and music), had managed to accomplish so much apparently dogged and persistent scientific work.
Kammerer unquestionably did have remarkable ability as an aquarianist, and he succeeded in maintaining and breeding various aquatic species that had previously resisted such culturing. He was trained in zoology at the University, and worked for his whole career at the famed and well-equipped (for its time) Institute for Experimental Biology on the Vienna Prater. Over a period of 26 years, Kammerer published a variety of studies with salamanders, toads, sea squirts, and other species. The results of many of these studies were presented as proof of the inheritance in the next generation of environmentally-acquired parental characteristics.
Kammerer's most celebrated evidence, the inheritance of acquired "nuptial pads" by midwife toad males, unfortunately proved to be his undoing. Kammerer averred that these small dark-colored protrusions on the male forelimbs, found in some toad species to be part of the clasping structures used in mating, could be induced environmentally in the midwife toad, and afterwards inherited by their male
offspring. In 1926, the noted American herpetologist, G.K. Noble, examined Kammerer's one remaining museum specimen of an experimental animal and discovered India ink in the so-called nuptial pad region. Thereafter, all of Kammerer's experimental work on Lamarckian inheritance, which had already been firmly at odds with advancing Mendelian theory, was dismissed as possibly fraudulent.
"To this end I was to teach them (praying mantids) a habit_a futile endeavor, since you could not teach the little beasts a thing. I was to feed them at the darkened bottom of their cage, but they preferred to eat high in the sunlight and firmly refused to change this sensible attitude for Kammerer's sake. I kept records, very exact records. That, too, annoyed Kammerer. Slightly less exact records with positive results would have pleased him more."
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KAMMERER HIMSELF had always maintained that his work on the sea squirt, Ciona intestinalis, was his most convincing proof of the inheritance of acquired characteristics, and the Koestler book described this work in some detail with the plaint that it had never been adequately reinvestigated with sufficient rigor to justify its dismissal. Strangely this Ciona work had never been published in full numerical detail by Kammerer, but only described in outline in various of his books and short papers. Kammerer purported to show that when the two siphon ends (see photographs page five and below) of this protochordate ascidian species were both amputated, the new siphon tubes became longer upon regeneration than the original tubes, and that the complete elongation was inherited by the next generation. The whole experiment supposedly involved two sequential siphon regenerations, after which a regeneration of a lower section of the body, containing the gonads, was caused to occur before the animals were crossed for the next generation.
Just after publication of the Koestler book, I attempted during two summers at the MBL to repeat parts of Kammerer's experiment. My results were later published (1975) in Nature magazine against the objections of Arthur Koestler. They apparently lacked aufficient rigor to refute Kammerer! In fact, by definition, negative findings always seem to lack aufficient rigor to refute positive claims. Ciona siphons did not, of course, regenerate longer after their surgical removal. But most telling was the gonadal regeneration part of Kammerer's supposed experiment. This involved a completely lethal operation from which animals could not recover, a fact known even in 1914 from experiments on Ciona byJan Hirschler. I was left with no remaining doubt that the Ciona results were also an invention of Paul Kammerer's highstrung imagination.
Around Naples and Southern Italy, there is a subpopulation of Ciona with distinctly longer siphons.
One feature of Kammerer's Ciona work had continued to puzzle me. This was an actual photograph of longsiphoned Cionas that he reproduced m one of his textbooks. These animals were claimed to be the first generation progeny arising from adults with regenerated siphons and gonads. And indeed, much was made by Koestler in his book about this concrete proof of Kammerer's results.
Alas, as I discovered several years ago, there are two distinct morphotypes of Ciona in the Mediterranean where Kammerer collected his animals. Populations of animals in northern parts of the basin and in the English Channel are of the short-siphoned kind found throughout the northern temperate regions of the world. Around Naples and southern Italy there is a subpopulation with quite distinctly longer siphons of the sort depicted by Kammerer as the result of his experiments. A photograph is shown here of such an animal collected by me in Sicily; all of the Cionas there, large and small, had the same elongated siphons. It seems likely that Dr. Kammerer was also an alert and observant traveler, and that he added "collecting" to his other hobbies and enthusiasms.
THERE WAS CERTAINLY contentiousness about Kammerer's various experiments even years before G. K.Noble found the doctored midwife toad specimen. Kammerer was a spirited and formidable adversary in defense of his work, and the many bloodlettings that occurred in the back alleys of Nature still remain quite entertaining reading. But some months after the revelation by Noble (also published in Nature), Kammerer, in a state of depression and despondency, and partly on account of an unhappy love affair, committed suicide. He did, however, achieve a rather exceptional last word. A final letter, asserting his innocence of fraud and postedjust before he killed himself, was published in Science magazine. Publication of a suicide note in a scientific journal, or at least something deliberately meant as such, must surely remain one of this strange man's most