Invertebrate Biology 123(3): 212-217. 0 2004 American Microscopical Society, Inc.

Anna Meyer and the distinction between grades and clades in early models of gastropod evolution

David R. Lindberg” and Benjamin L. Matzen

Department of Integrative Biology and Museum of Paleontology, University of California, Berkeley, California 94720, USA

Abstract. Anna Meyer published her first (and apparently last) scientific paper in 1913, in which she reported, in part, on the organization of the renogenital systems in the “Diotocardia” and “Monotocardia,” and the evolutionary signal present in this character suite. Meyer’s phy- logeny broke with conventional wisdom of her time and she reconstructed early gastropod evolution as a sequence of branching events rather than a continuous grade. Her phylogeny was ignored because it did not correspond to the well-ordered grades that came to dominate gastropod systematics for over 75 years, but her schematics of renogenital configurations have been featured in the literature for over 55 years, sometimes without citation and redrawn to show a different set of relationships. We hope that the translation of her paper from German into English (http://www. ucmp. berkeley. edu/collections/archdut. html) will make her contribu- tion more accessible to workers.

Additional key words: renogenital, systematics, Mollusca, Annelida, phylogeny

In 1913 Anna Meyer published her first (and ap- parently last) scientific paper. In it she undertook a study of the renogenital system of the fissurellid gas- tropod Puncturella noachinu (LINNAEUS 1758), and in- terpreted her findings to address evolutionary relation- ships among the Gastropoda. Meyer undertook her study at the suggestion and under the guidance of her father, Professor Eduard A. Meyer of the University of Kazan (Tatarstan, Russia Federation). The specimens she studied had been collected for her by her father’s assistants who also provided advice and assistance with her research (Meyer 1913). While biographical material on Anna Meyer appears to be nonexistent, her father’s life and role in invertebrate biology can be documented from the archives of the Stazione Zoolo- gica Anton Dohrn (Naples, Italy) (C. Groeben, pers. comm.), and the University of Kazan (Vagin, 1979), and these resources provide an important timeline and context from which to appreciate Anna Meyer’s con- tribution.

Timeline and intellectual pedigree

Eduard Alexandrejewitsch Meyer was born in 1859 to a bourgeois German family in St. Petersburg, Rus- sia. Upon completion of studies at St. Petersburg Uni- versity in 1882 (where he specialized in microscopy

Author for correspondence. E-mail: drl@uclink.Berkeley.Edu

under E V. Ovsyannikova), Meyer traveled to the “Zoologischer Station” at Naples, Italy where he was entered on the general list of guest investigators as “Candidate from St. Petersburg 23.09.1882- 01.06.1884” (ASZN: G.LVI.73). In March 1883 he became an assistant to Professor Anton Dohrn, founder and director of the Station, and it was here that he received his primary training in invertebrate biology, surrounded by the preeminent morphologists of his day, including Dohrn, Arnold Lang, Johann Wilhelm Spengel, Hugo Eisig, and Wilhelm Giesbrecht.

In 1887 he married Catharina Lohrer, a German woman from St. Petersburg who had arrived in Naples as a governess with an affluent Russian family. Al- though not an official policy, it was Dohrn’s view that station life was not for married men. Dohrn felt that life in Naples required a certain standard of living, and because he was constantly struggling to procure finan- cial support for the station’s survival, he knew he could not guarantee a salary that would feed a couple or a family (C. Groeben, pers. comm.). Other evidence €or Dohrn’s sentiment is found in his remarks regard- ing another assistant-the Swiss zoologist Arnold Lang. When Lang announced his intention to get mar- ried in 1888, Dohrn commented to his wife that this would be a good excuse for Lang to leave Naples be- cause of the low salary (with no guarantee for the fu- ture) and the difficulties associated with fitting in with

Anna Meyer and gastropod evolution 213

the other assistants (C. Groeben, pers. comm.). Cor- respondence between Meyer and Eisig indicates that Meyer knew of Dohrn’s feelings (C. Groeben, pers. comm.), and in 1889 Meyer left the station and re- turned to St. Petersburg, Russia with his wife.

On the trip from Naples to St. Petersburg, Meyer visited colleagues, and was likely inquiring on possible jobs. He stopped in Munich and visited K. N. Davy- dov, and then went to Berlin and visited H. Virchow. In St. Petersburg he visited Professor N. l? Vagner who advised him to finish his degrees as soon as possible so that he would be competitive for upcoming Profes- sorships in Warsaw, Krakow, and Kazan (ASZN: A.1889.M). Meyer spent a year and a half in Warsaw in the Zoological Department of the University before moving to Kazan in 1891, where he became an assis- tant to Professor M. M. Usov.

Usov was apparently impressed by Meyer and in I 894 Usov transferred the teaching responsibility for the Department’s required course in histology to Mey- er. In 1898 Meyer received his doctorate from St. Pe- tersburg University with a dissertation on the embry- ology and morphological evolution of polychaete worms. After receiving his degree Meyer had expected to succeed Usov in the Chair at Kazan and was dis- appointed when the position went to the Porifera tax- onomist N. N. Polkjaeff in 1900. In a letter to Anton Dohrn, Meyer stated that “the chair from Usov went at PoEjaeff!, although I have exerted myself here for 10 years. . . . [this is the] work of my enemy Melni- kov, . . .” (ASZN: A.1900.M). During 1901 Meyer en- listed the help of numerous invertebrate biologists, many of whom were or had been associated with the Stazione in Naples or the Zootomical Cabinet (the De- partment of Invertebrate Zoology) at St. Petersburg University. W. W. Salensky, A. 0. Kowalewsky, R.S. Bergh, H. Eisig, J. Kennel, W. Kiickenthal, and A. A. Ostroumov, all joined Dohrn in the “intervention,” and wrote letters on Meyer’s behalf. In 1902 Eduard A. Meyer was appointed Professor at Kazan.

The Department and Museum at Kazan flourished under Meyer and his assistants. Meyer restructured the teaching program, and greatly improved and expanded the zoological collections and research infrastructure. Histology, embryology, comparative anatomy, and in- vertebrate zoology were the mainstays of his program. Meyer’s strong leadership and organizational abilities (which are thought to have been acquired in Naples with Anton Dohrn) brought about a considerable in- crease in the number of students in the program (Vagin 1979).

In addition to being the year of Anna Meyer’s only publication, 1913 also marked the sudden departure of Eduard Meyer (and presumably the family) from Ka-

zan. By 1912 Eduard Meyer had become increasingly embroiled in politics and at odds with several mon- archist professors, one of whom (Kasso) would ulti- mately head the Ministry of Public Education in St. Petersburg (Vagin, 1979). Kasso became notorious for his use of the secret police to spy on secondary school students and teachers, and Kazan’s reputation as a cen- ter of intellectual and revolutionary activity in Russia undoubtedly did not help Meyer. Kazan students had included L. Tolstoy, V. I. Lenin, and D. Karakozov (who attempted to assassinate Tsar Alexander I1 in 1866), and between 1906 and 1910 the Ministry of Public Education removed 2 1 head masters of second- ary and primary schools, 32 inspectors of public schools and 1,054 urban school teachers from the Ka- zan area alone (Lenin 1968). It is also interesting to note that V. T. Schewiakoff, who also knew Meyer and was the former Chair of the Zootomical Cabinet at St. Petersburg University, was vice-minister in the Min- istry of Public Education at the time of Meyer’s dis- missal (191 1-1917). Meyer traveled to St. Petersburg to appeal the decision to the Ministry, but the final outcome was his loss of the Professorship; he left Ka- zan on a Volga steamship for Moscow, arriving there before December 19 13.

After temporary positions at the Free University of Shenyavskogo in Moscow and at Tbilisi State Univer- sity (Georgia), Meyer moved to Simferopol (Ukraine) in 1918 and became Chair & Professor of Zoology in the newly opened university there. In 1918 N. A. Liv- anov (one of Meyer’s former assistants at Kazan) ini- tiated the first of several attempts to return Meyer to Kazan, but the front lines of the Russian Civil War prevented Meyer from returning. In 1921 Meyer stepped down as Chair of the Zoology Department and in 1927 he and his family moved to Krasnodar (Russia Federation) where Eduard Meyer died of pneumonia at the age of 69 in June 1928.

From the above outline of her father’s life, it appears that Anna Meyer’s training, access to resources, and the intellectual setting in which she conducted her study of Punctureella noachina was excellent and, based on the closing remarks in her paper, she had conducted (or was conducting) other “scientific stud- ies” at that time. The lack of subsequent publications and her apparent departure from science may well be linked, in part, to the termination of her father’s po- sition at the University of Kazan just months after the publication of her paper. It would be almost 5 years until her father once again found secure employment; this during a period when life in Russia was further destabilized by World War I (1914-1918), the Russian Revolution (1917), and the Russian Civil Wars of 1918-1922.

214 Lindberg & Matzen

Anna was likely in her early twenties at the time of publication of her paper. Eduard Meyer and his wife left Naples in August 1889. The first mention of a child is in correspondence in 1893 (ASZN: A. 1893.M). Therefore, Anna was most likely born be- tween 1890 and 1893, and at the time of publication of her paper in September of 1913, the oldest she could have been is 23 years old-making her one of the youngest molluscan phylogeneticists of the 20th century. There is also an indication that Anna was in- terested in animals and nature at an early age. Writing to Hugo Eisig at the Stazione in 1898, Eduard Meyer commented that the wilderness around Kazan was home to “many wild animals” and that the next time he went out “. . . our daughter, on whom a good boy is lost, will accompany me on a hunt; she displays a passionate interest in this sport.” [ASZN: Bb.9741. The phrase “on whom a good boy is lost” (an der ein guter Junge verloren gegangen ist) is a reference that his daughter behaved more like a boy than a girl. Her interest in hunting, and perhaps the accompanying field experiences, suggest that as a young girl (5-8 years old) Anna may have already had a strong attrac- tion to the outdoors and nature,

Anna Meyer and the phylogeny of gastropod molluscs

Anna Meyer’s paper is organized into 7 informal sections: (1) introduction, (2) previous work, (3) re- sults of her dissections and microscopic studies, (4) comparison of her results to previous work, (5 ) com- parisons of her results with other taxa, (6) a hypothesis for early gastropod evolution, and (7) acknowledge- ments. Sections 5 and 6 deserve further comment. In section 5 Meyer compared the renogenital organization of Puncturella noachina to several ‘Diotocardia’ and ‘Monotocardia’ taxa in an explicit phylogenetic con- text. The tree was not independent of her renogenital character set, and she constructed it as she went through her character analysis. This is readily apparent in the numbering of her figures on the tree (reproduced here as Fig. l ) , which reflect the sequence of events rather than the position of figures on the page.

Meyer paid attention to homology and appears to have looked for the most parsimonious sequence of character state transformations (Table 1). In both of these undertakings she was well served by her use of hypothetical taxa-somewhat equivalent to the HTU (hypothetical taxonomic unit) in modern cladistic anal- yses. For example, in section 6 she argued that the differential reduction of the nephridia in the ‘Mono- tocardia’ (left side) and the ‘Diotocardia’ (right side) indicated two separate and deep evolutionary lineages

within the Gastropoda. Her use of taxon 2 in Fig. 1 provided an important intermediate condition, not rep- resented in living gastropods, from which to branch these two separate lineages. Comparisons then with the character transformations seen in the ‘Diotocardia’ led her to hypothesize a similar set of developmental events in the ‘Monotocardia’ (albeit on the opposite side of body) (Table 1). This required hypothetical tax- on 7 (Fig. 1).

Through the 1960s, most scenarios of gastropod evolution based on the renogenital system had the monotocardians derived from a diotocardian ancestor similar to living trochacean gastropods (e.g., Thiele 1895; Pelseneer 1906; Goodrich 1945: fig. 87; Fretter & Graham 1962: p. 618). This rendered early gastro- pod evolution as a continuous grade rather than a se- quence of branching events giving rise to clades (see also Hickman 1988; Haszprunar 1993). Meyer’s phy- logeny also broke with the conventional wisdom of her time because the trochid, which shared character states with Haliotis and Pleurotomaria, was placed ‘above’ taxon 6 in her tree (Fig. 1) and was therefore not even considered by her as a putative ancestor of the ‘Mon- tocardia. ’

While it is pointless to discuss whether or not Anna Meyer was an “Ur-cladist,” the method she used in constructing her arguments and evaluating others was clearly based on ordering character states relative to an evolutionary model and using differential devel- opment patterns to account for variation. She, of course, did not get everything “right” by today’s stan- dards. An over zealous use of character weighting put substantial emphasis on secondary shell flattening and placed Patella between the limpets Puncturella and Fissurella. She used extant taxa as HTUs in her tree, and mistook variation in living taxa as indications of past evolutionary intermediates or harbingers of future evolutionary directions, and there is no doubt that she heavily weighted renogenital characters over all other characters. However, parts of her methodology were surprisingly modern and her phylogenetic result ro- bust, although it would languish for the next 75 years because Thiele’s (1 925) grade-like classification was adopted in almost all subsequent major treatises and texts (see Lindberg & Ponder 2001).

Although there is no metric to determine obscurity, we tried to gage the community’s awareness of Meyer (19 13) by looking at the number of citations her paper has received over the last 90 years. We did this by looking at major books and volumes in molluscan bi- ology and systematics and by using an electronic da- tabase search of journal citations. Both approaches have problems, some of which are noted below. But our sense that Meyer has been overlooked by most

Anna Meyer and gastropod evolution 215

Diotocardia

5 ;_----.__ ,------- .. . 6

Haliotis

Patella

Monotocardia

_--.- - _ 8

1 st stage

Progastropoda

2nd stage

Fig. 1. Meyer’s (1913) “Schematic representation of the renogenital system of the basal gastropods and their phylogenetic relations.” Orig- inal caption from Meyer (1913: p. 571) translated from German. Organ and structure labels added to 1 s t stage for clarity.

Table 1. Change list for Meyer’s renogenital characters based on her text and figure. All orientations are post-torsional.

Character Changes

Loss of left gonad Reduction right nephridia Reduction left nephridia Loss of left gonoduct Loss of left renopericardial canal Papillary sac Loss of right nephridia Loss of right renopericardial canal

Progastropoda -+ HTU 2 HTU 2 -+ HTU 7 (Promonotocardia) HTU 2 -+ Prodiotocarida & Puncturella Prodiotocarida & Puncturella + Patella Prodiotocarida & Puncturella + Fissurella Prodiotocarida & Puncturella + Haliotis HTU 7 (Promonotocardia) 4 Monotocardia

216 Lindberg & Matzen

workers was also borne out by the results of our sur- vey. For example, there are no citations to Meyer in the some of the major books of the last 20 years, in- cluding “The Mollusca” (Wilbur 1983-1988), “Pros- obranch Phylogeny” (Ponder 1988), “Origin and Evo- lutionary Radiation of the Mollusca” (Taylor 1996), and “Mollusca. The Southern Synthesis” (Beesley et al. 1998). Meyer is cited in papers by Rammelmeyer (1925) and Ziegenhorn & Thiem (1925), and in “Brit- ish Prosobranch Molluscs” (Fretter & Graham 1962), “Physiology of Mollusca” (Wilbur & Yonge 1964), and “The Invertebrates” (Hyman 1967). However, all cite her paper only in the context of renal morphology, not gastropod phylogeny.

Since 1945 (the beginning date for journals covered by the citation reference database IS1 Web of Sci- ence@), Meyer (1913) is reported as only being cited twice. In contrast, Andrews’ (1985) paper, on the structure, function, and evolutionary significance of the excretory systems of archaeogastropods, has been cited 32 times, and in just 18 rather than 58 years. Undoubtedly there are problems with the above com- parison. Certainly, there is a strong ‘pull of the Recent’ phenomenon (Raup 1979) at work here when compar- ing citations for a 1913 German paper with a 1985 English paper. But an even earlier publication by Goodrich (1 893, on the morphology and evolution of nephridia and genital ducts of the “invertebrata,” is also better cited than Meyer, with 24 references in 58 years.

Although the above searches suggest that Meyer’s work is seldom cited and therefore is relatively unfa- miliar to most workers, her diagrams, and to a lesser extent her evolutionary scenario, have been promi- nently featured in the molluscan literature for over 55 years. C. M. Yonge (1947) cited and used both Mey- er’s phylogeny and her schematic drawings of the ren- ogenital systems in his seminal paper on the evolution of the pallial organs in the aspidobranch gastropods. Although Yonge (1947) modified Meyer’s diagram as his figure 30, eight schematic diagrams, hypothetical ancestral states, and the purported relationships and transformations are identical to Meyer’s phylogeny and figures. In his chapter on “General Characters of Mollusca” in the influential series “Treatise of Inver- tebrate Paleontology,” Yonge (1960: fig. 8) repro- duced a further modified Meyer phylogeny of the ren- ogenital system. Although Meyer’s diagram of the evolution of the gastropod renogenital system is absent in Morton & Yonge (1964: fig. 6), five of her reno- genital character state diagrams are present. All three of these publications represent major contributions in 20th century malacology, and components of Meyer’s (1913) paper are present in all. As time passed her

phylogeny was forgotten because it did not correspond to the well-ordered grades of Thiele (1925), but her schematics of renogenital configurations were there; sometimes incorrectly cited which further contributed to the obscurity of her work (e.g., Franc 1968).

Although her phylogenetic hypothesis for the early evolution of the Gastropoda was not in favor for much of the 20th century, it ultimately (with the exception of the derivation of the Patellogastropoda) would come to be supported by both morphological and molecular analysis of gastropod relationships (Lindberg et al. 2004 and references therein). And like the older lit- erature discussed above, more recent workers have also overlooked Meyer (e.g., Andrews 1985; Haszpru- nar 1988; Ponder & Lindberg 1997; Sasaki 1998).

Anna, like her father before her, focused her re- search on coelomic cavities and their evolutionary sig- nificance and development-a major theme of the in- vestigations of many of the invertebrate biologists of the Stazione Zoologica di Napoli. Similar investiga- tions were also being done by zoologists associated with Anna’s father through the Zootomical Cabinet at St. Petersburg University. Today this body of work, which produced the theory of the coelom, forms a cen- tral tenet of invertebrate biology and integrates devel- opment, physiology, and biomechanics with inverte- brate evolution and classification (e.g., Brusca & Brusca 2002, Buchsbauin et al. 1987, Pechenik 2000).

Anna Meyer remains a dim figure in early 20th cen- tury invertebrate biology, but her work and the insights from her single paper have been in front of us for over 50 years. Her intellectual pedigree as a “Darwinian morphologist” extends through her father, Eduard A. Meyer, to Anton Dohrn, Ernst Haeckel, and with three degrees of separation to Thomas Huxley. It also in- cludes many of the most distinguished Russian and German invertebrate biologists of the late 19th and early 20th centuries. While we cannot further illumi- nate Anna Meyer the person, we hope that the trans- lation of her paper into English (see below) will insure that her contribution becomes more obvious and avail- able to future workers.

Acknowledgements. We are grateful to Christiane Groeben (Coordinator, History of Science Unit, Stazione Zoologica Anton Dohrn) and Natalja Zinkina (Information Technolo- gies Centre of the Kazan State University) for providing in- formation on Prof. Eduard A. Meyer from the archives of the Stazione Zoologica di Napoli and the University of Ka- zan, respectively. We thank George and Vald Shurkin for guidance and assistance in the translation of Russian docu- ments, Gerhard Haszprunar (Zoologischen Staatssammlung Munchen) for assistance in the translation of German doc- uments, and Michael T. Ghiselin (California Academy of Sciences) for linking Eduard Meyer to the Naples Station.

Anna Meyer and gastropod evolution 217

Elizabeth Andrews (Royal Holloway, University of London), Michael T. Ghiselin, Winston E Ponder (Australian Museum, Sydney), Mary l? Winsor (University of Toronto), and an anonymous reviewer provided helpful comments and criti- cism of the manuscript. An English translation of Meyer (1913) is available in PDF format at http:// www. ucrnp. berkeley.edu/collections/archdat. html. This is contribution number 1829 from the University of California Museum of Paleontology.

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