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Bathybius Haeckelii and the Psychology of Scientific Discovery

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Bathybius Haeckelii and the Psychology of Scientific Discovery NICOLAAS A. RUPKE BATHYBIUS HAECKELII AND THE PSYCHOLOGY OF SCIENTIFIC DISCOVERY THEORY INSTEAD OF OBSERVED DATA CONTROLLED THE LATE 19th CENTURY ‘DISCOVERY’ OF A PRIMITIVE FORM OF LIFE THE TRADITIONAL image of the scientist as an objective fact finder has become seriously tarnished by recent work in the history and philosophy of science. ’ It is argued that the growth of science is not always brought about by a reasoned debate based on objective evidence. Instead, scientific discovery seems to be controlled quite as much by certain psychological factors such as respect for a theoretical superstructure. The debate around T. S. Kuhn’s The Structure of Scientific Revolutions has brought similar iconoclastic aspects of scientific conduct to the attention of a cross section of the scholarly community.’ Without wanting to enter into the controversy generated by Kuhn’s book,3 this paper records one of the better examples from the annals of science to show how respect for a theoretical superstructure brought about a fictitious discovery. Specifically, it records how confidence in the heuristic value of evolutionary theory in the second half of the 19th century produced the discovery of a fictitious primitive form of life, called Bathybius, its sub-division into two genera, its reported occur- rence over vast regions of the ocean floor, its identification in the geologic record, and its wide acceptance in the life and earth sciences for the period of almost a decade. Background to the ‘Discovery’ Shortly after the publication of Darwin’s The Ongin of Species (1859), 1 See review paper by S. G. Brush, Science 183, 1164 (1974). 2T. S. Kuhn, The Structure of Scientific Reuolutions Univ. of Chicago Press, Chicago, 2nd edn., 1970. 3See for example Ctiticism nnd the Growth of Knowledge, I. Lakatos and A. Musgrave (eds.) Cambridge Univ. Press, Cambridge, 1970. Stud. Hist. Phil. Sci 7.( 1976), No. 1. Printed in Great Britain 53 54 Studies in History and Philosophy of Science the conceptual need was felt by a number of Darwin’s supporters to link the late 18th century nebular hypothesis of planetary evolution with the hypothesis of organic evolution and establish by that the philosophy of ‘universal transformism’. The link was thought to consist of factual evidence for the origin of life out of inorganic matter, i.e. a&genesis. Howeyer, at about the same time, Pasteur conducted his classic experiments on fermentation (1860-1866) and made a cogent case for the germ theory of fermentation and against abiogenesis. In the midst of the controversy generated by Pasteur’s experiments, the German zoologist E. H. Haeckel reported in his Generelle Morph- ologie der Organismen (1866) on the existence of a group of very primitive microbes, which he called Monera.’ A Moneron was defined as a primitive form of life consisting of undifferentiated protoplasm and lacking a nucleus. In a separate monograph on this group, Haeckel described in some detail a number of different Moneru, among which the most primitive of all which he called Protamoeba primitiu6 It was described as being entirely homogeneous and reproducing itself by process of binary fission (Figure 1). The primitive level of organization of the Monera was interpreted to indicate that the group represented life in statu nascendi, and as such it made abiogenesis conceivable. Figure 1 Protamoeba primitiva (Haeckel), O-04 mm in dia (From reference 13). The ‘Discovery’ of Bathybius At about the same time that Haeckel announced the existence of the Moneru, the English zoologist T. H. Huxley examined a number (he did not mention how many) of mud samples dredged during an 1857 4L Pasteur, Ann Sci nut. Part. Zoo1 16, 5 (1861). SE. H. Haeckel, Generelle Mosphologie de7 Organismen (Berlin, 1866) p. 135. 6E. H. Haeckel, Jenu Z Med Naturw. 4,64 (1868). Bathybius Haeckeliiand the Psychology of Scientific Discovery 55 expedition aboard the ‘Cyclops’ northwest of Ireland. The mud samples had been preserved in alcohol. Huxley, employing a special microscope with ‘a magnifying power of 1200 diameters’, 7 observed in the ooze a gelatinous substance with a granular texture. He interpreted this as protoplasm in a primitive state of organization and identified it as one of Haeckel’s Moneru. In a paper ‘On some organisms living at great depths in the North Atlantic Ocean’ (1868) he wrote: ‘I conceive that the granule-heaps and the transparent gelatinous matter in which they are imbedded represent masses of protoplasm. Take away the cysts which characterise the Radiolaria, and a dead Sphaeroroum would very nearly resemble one of the masses of this deep-sea “Urschleim”, which must, I think, be regarded as a new form of those simple animated beings which have recently been so well described by Haeckel in his “Monographie der Moneren”. I propose to confer upon this new “Moner” the generic name of Bathybius, and to call it after the eminent Professor of Zoology in the University of Jena, B. Hueckelii ‘7 Inside the gelatinous substance Huxley identified two types of coccoliths which he called Cyatholithi and Discolithi. These he interpreted to be skeletal components of Bathybius Haeckelii, like spicules in sponges (Fig. 2). Figure 2 Bathybius Haeckelii (Huxley), O-1 mm in dia (From reference 10). 56 Studies in History and Philosophy of Science The existence of Bathybius was confirmed by Sir Charles Wyville Thompson who later was to become the chief scientist to the ‘Challenger’ expedition. Thompson examined an ooze sample from the Atlantic Ocean floor and he remarked in a paper ‘On the depths of the sea’ (1869): ‘This mud was actially alive; it stuck together in lumps, as if there were white of egg mixed with it; and the glairy mass proved, under the microscope, to be a living sarcode. Prof. Huxley regards this as a distinct creature, and calls it Bathybius. ” In more detail Wyville Thompson described Bathybius in his classic of oceanography The Depths of the Sea ( 1873).9 In his ‘BeitrZge zur Plastidentheorie’ (1870), Haeckel exaggerated Huxley’s report by interpreting it to mean ‘that the sea floor of the open ocean at greater depths (below 5000 ft) is covered with enormous masses of free living protoplasm’.” He enthusiastically remarked that the discovery of Bathybius had turned the ‘Urschleim’ of the German ‘Naturphilosophie’ into a complete truth. Haeckel had himself obtained one sample of deep-sea mud, dredged by Wyville Thompson and W. B. Carpenter off the south-west coast of Ireland. The sample had been sent to him preserved in alcohol. Haeckel also observed the gelatinous substance with its granular texture which he coloured with a carmine solution and interpreted as real protoplasm. He thought it likely, though not entirely certain, that the coccoliths were skeletal compon- ents of Bathybius. Huxley accepted Haeckel’s exaggeration of his 1868 report and he added to this an exaggerated account of Haeckel’s description of Bathybius in a speech before the Royal Geographical Society in 1870. He said with respect to his by now reputed discovery: ‘Evidence of its existence had been found throughout the whole North and South Atlantic, and wherever the Indian Ocean had been surveyed, so that it probably forms one continuous scum of living matter girding the whole surface of the earth. This opinion has been confirmed in all its essential details by Prof. Haeckel, who had published an admirable account of specimens obtained by him.’ l1 The existence of masses of free protoplasm or ‘Urschleim’ on the sea floor was even more suggestive of a form of life in statu nascendi than Protamoeba primitiva. In a speech on ‘Das Leben in den griissten Meerestiefen’ (1870) Haeckel expressed the belief that it ‘was virtually certain that Bathybius originated by process of abiogenesis. More in general he argued that the question of the origin of life could not be 7T. H. Huxley, Quart. J. Microsc. London 8, 203 (1868). *c. W. Thompson, Ann Mug. nut. Hist. 4, 112 (1869). gC. W. Thompson, The Depths of the Sea (London, 1873) p. 410. 10~. H. Haeckel, Jena. Z Med Naturw. 5, 492 (1870). 11~. H. Huxley, Proc. R geogrl. Sot. 15, 37 (1871). Bathybius Haeckeliiand the Psychology of Scientific Discovery 57 solved by experiment (an apparent reference to Pasteur), but only through a philosophical approach. l2 The discovery of Bathybius and of the other Monera established the link between planetary evolution and organic evolution. In his widely read Natiirliche Sch6pf&zgsgeschichte (1870) Haeckel explicitly wrote: ‘Whenever previously one tried to visualize abiogenesis, one immediately faiied as a result of the organic composition of even the most simple organisms that one knew at the time. This main problem has been solved only since we have become to know the extremely important Monera, only since we have understood them as organisms that are not at all made up of organs, that consist of just a single chemical compound, and that still grow, feed, and reproduce. As a result, the hypothesis of abiogenesis has gained such a degree of probability as to entitle it to fill the gap between Kant’s cosmogeny and Lamarck’s theory of evolution. Already among the Monera known up till now, one type exists which still today probably continuously originates by abiogenesis. This is the marvellous Bathybius Haeckelii, discovered and described by Huxley.‘13 The Bathybius bandwagon The discovery of Bathybius Haeckelii generated a great deal of excitement in the life and earth sciences and a number of biologists and geologists continued the investigation of this Moneron. The German biologist 0. Schmidt reported in a paper ‘uber Coccolithen and Rhabdolithen’ (1870) that in the course of an oceanoLgraphic expedi- tion in the Adriatic Sea he had found evidence of the existence of Bathybius there as well.
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