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International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
Protist, Vol. 155, 361–370, September 2004 http://www.elsevier.de/protist Published online 14 September 2004
Protist
FROM THE ARCHIVES
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia Dieter Mollenhauer1 Forschungsinstitut Senckenberg, Frankfurt am Main, Forschungsstation für Mittelgebirge, Lochmühle 2, 63599 Biebergemünd, Germany Kennst du das Land, wo die Zitronen blühn? [Do you know the land where lemons bloom?] Goethe: Lied der Mignon, Wilhelm Meisters theatralische Sendung, 4 (1)
Phycology on Tortuous Pathways In his magnificent two-volume “Structure and Reproduction of the Algae” Felix Eugen Fritsch (1879–1954) single-handedly provides us with his era’s ultimate summary of phycological knowledge. His works were published in 1935 and 1945, respectively. The two key words in the titles of Fritsch’s book are also appropriate to characterize the main trend of research in the period between 1850 and 1950. Algae were mainly studied to comprehend how they are organized and how this organization is brought about in the course of ontogenetic development. These organisms are particularly suited to provide one with an understanding of how growth results from cell division. In turn, comparative studies of cytokinesis yield insights into the phenomenon that the formation of new cellular walls and karyokinesis in algae, like in higher plants, can be linked although this is not a must (formation of siphoneous or siphonocladalean organization). Many general concepts of plant cytology and anatomy are derived from the study of algae. By giving the scientific Linnean name Fucus to the well-known littoral organisms living in the sea botanists also introduced the “model of an alga”. Thus, in early phycology, the “type seaweed”, i.e. kelp (in Britain and Scotland), varech [varec] (in France outside of Brittany), goémon (in Brittany, 1
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France), tang (in Nordic countries and Germany), became the standard of comparison for all other organisms whose character as algae was under debate. This is also the reason why brown algae in the early literature are collectively named Fucoideae C.A. Agardh (synonymous with Phaeosporeae Thuret, Melanospermeae Harvey and Melanophyceae Stizenberger). We are not sure whether “fucus” was really the name of an alga in GraecoRoman times. Moreover, looking for the understanding of the Latin word “fucus” or its Greek counterpart “ϕυ′κος” is of little help. In the end, the real meaning of “fucus” remains obscure, especially since it was seen as a type of beauty product rather than as a category of living beings. Initially, aquatic organisms other than Fucoideae were not named “algae”. Therefore, the older literature is full of notions like “conferva”, “lichen”, “muscus”, “tremella” or even “corallina”. Definitions of categories in biodiversity research are principally unstable since they always only reflect the status of current knowledge. If, in lucky cases, they are very precise, they are of the type of aphorisms, or better: epigrams. Consequently, in the field of biology, the need for flexibility reflective of the research progress on the one hand, and the need for stability for the purpose of systematic and nomenclatural orderliness on the other, are in permanent conflict. The biohistorian has to be aware of this fact and must 1434-4610/04/155/03-361 $ 30.00/0
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use current notions carefully when interpreting the past. What naturalists understood by algae changed thoroughly in the era of early inventories. Among the pioneers who brought together under a common name some of so many very dissimilar living beings and who defined the term “alga” in the first approaches were the early marine naturalists from the British Isles, France, Italy and Spain, and also some seasiders of other countries (Denmark, Germany – including those who then did service in Russia, the Netherlands, Sweden). The following list of names includes only some of many names: Adanson, C.A. Agardh, Bailey, Bivona, Bonnemaison, Bory de St. Vincent, Decaisne, De la Pylaie, Derbès, Dumortier, Fries, Ginnani, S.F. Gray, Greville, W.H. Harvey, Hering, Hooker, Hornemann, Kützing, Lamarck, Lamouroux, Link, Lyngbye, Meneghini, Montagne, O.F. Müller, Postels, Roth, Ruprecht, Solier, Sonder, Stackhouse, Zanardini. In the late 18th and early 19th centuries phycology is characterized by inventories (surveys of flora and vegetation) and more or less successful attempts to reconcile categories as unlike to each other as unicellular forms (infusoria), filamentous microphytes (Conferva), and large plant-like kelps. The study of ontogeny proved to be the most effective means by which to reveal relations that are not obvious if only the outer habit is compared. So, the different groups that finally were to form the Phaeophyceae were brought together by and by. This division was given the name we still use today as late as 1885 by Ferdinand Hauck (1845–1889). Before then the kelps and the filamentous brown algae were kept separate in different orders. As soon as phylogenetic thinking seized the whole of biology, matters were turned upside down. Now, the simple (early?) representatives of a group of presumably or obviously related organisms became the research subjects of special interest. Investigations concentrated on forerunners, ancestral forms, or whatever designations were given to organisms that were considered to be at the roots of a given line of evolutionary advance. This may be best illustrated by the study of sexuality, a study area which has fascinated biologists for centuries. For example, the final detection of the most fundamental process, i.e. fusion of two cells, male and female, can be clearly seen in algae. However, this interpretation of a very simple observation was only possible with an appropriate concept of sexuality. In algae, in special cases, two individuals formed by two single cells fuse to form the zygote. Thus, it is shown with all necessary clarity that sexuality and multiplication have to be kept separate in considering what reproduction of organisms means
and studying the ways how it is accomplished. This was the end of a very long discussion with many wrong turns and grotesque situations. Instead of useless speculation, observation of simple organisms clarified this matter. As we shall see, some marine algae were ideal for this purpose.
The Germans and Austrians and the Mediterranean – Two Extraterritorial Biological Stations Of course, Germany has seashores at both, the North Sea (sometimes still called “German Ocean”) and the Baltic. However, longing for and traveling to Italy (and the Mediterranean region in general) is a matter of German literary history. German speaking literary historians use the notion “topos” for such permanent feeling. Italian history, art, literature, landscape, fashion, wines, and cookery are in their entirety also a general concern of German culture (Waetzold 1927). Many Danish people are also fascinated by the Mediterranean and ever since the late 18th and in the 19th centuries haven been going there every year. During a rather long period in Central European history, only the ruling nobility, soldiers, pilgrims, tradesmen and traveling scholars were on the road. Educational journeys became popular in the 17th and 18th century. In the 19th century, financial conditions and the available means of public transport made tourism possible not only for the upper, but also for the middle classes of the society. To go and see the biota of the seashore, the high Alps and the Mediterranean, each of these at least once, became not only highly recommended but compulsory for all biologists. Many organisms from the South became especially well-known research objects and textbook cases of general botany. This was accomplished by intimate scientific cooperation and exchange of ideas between naturalists from the British Isles, Scandinavia, West, Central und East Central Europe on the one hand and those from Italy, and later, also from Spain and Greece on the other. In the field of phycology scientists from France, who had access to seashores in the North, West and South, played a special role. In many respects they acted as pioneers and trailblazers. Furthermore, biologists from the North liked to go themselves to the Mediterranean, and they still continue to do so. Nearly all botanists of high reputation in the 19th century spared neither effort nor expense to experience the Mediterranean nature. Topics and destinations of their travels varied, but the mainspring of all these journeys was the same. However, for the
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
French as well as for the Austrian colleagues the situation was different since the territories of both countries then included Mediterranean coasts. In the case of France this was the gorgeous landscape of the Côte d’Azur (or Riviera, as the Germans say with an Italian notion) and the further coastal area between Alpes Maritimes and Pyrénées. The Austro-Hungarian Empire had its “crownland” Triest (Trieste) and its coastland (“Küstenland”) in Dalmatia. Thus, to Austrians and Southern Germans, especially those living in Munich, the notion of “the Sea” denotes not so much the North Sea or the Baltic. The latter are only natural points of reference for Central and Northern Germans. By contrast, the seaside resorts the Bavarians and Austrians mostly think of are situated around the Adriatic Sea. These now well-established bonds between people and landscapes were established by the early travelers in the 18th and 19th centuries. Anyhow, many non-Mediterranean naturalists and scientists then traveled to the South. Among those who came early was our famous German poet Johann Wolfgang von Goethe (1749–1832) who went to Italy for three reasons: To escape trouble at the ducal court in Weimar, to study art and to experience the Southern nature. One of his admirers was the Swedish Carl Adolph Agardh (1785–1859) who followed the tracks of his idol in Italy and Bohemia in 1827 (Mollenhauer 2002). Friedrich Traugott Kützing (1807–1893) went to Italy mainly as a collector of plants. At that time many naturalists subscribed for exsiccata collections brought together by experienced botanists. The latter sold parts in advance (then called “Aktien”) and used the money to pay their own travel costs. Kützing, before obtaining a permanent position in Nordhausen, did so, too (Müller and Zaunick 1960). Nathanael Pringsheim (1823–1894) and Ferdinand Cohn (1828–1898) wanted to see Gustave-Adolphe Thuret (1817–1875) and/or his famous garden at Antibes which was a “Tusculum” as well as a destination for botanical pilgrimages (Cohn 1901). Ernst Haeckel (1834–1919) and his colleague in Jena, Eduard Strasburger (1844–1912), also liked to go to the Mediterranean. The Zurich people, Carl Nägeli (1817–1891) and Carl Cramer (1831–1901), Nägeli’s student and later the successor to his chair, saw Naples with Mount Vesuvius and the Amalfi coast, collected algae there and studied them on the collecting site and at home after returning to Zurich. Equally, the circles arount Anton de Bary (1831–1888) and Johannes Reinke (1849–1931), chose the same destination. The two leading personalities kept strictly apart. Their colleagues and students, however, did not join them in their “separatism”. Count Hermann zu Solms-
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Laubach (1842–1915), student and later successor of A. de Bary, also kept friendly relations and cooperated with Reinke when both were professors of botany in Göttingen. The others, Michael Woronin (1838–1903), Friedrich Schmitz (1850–1895), Gottfried Berthold (1854–1937), and Paul Falkenberg (1848–1925), were more exclusively associated with their respective teachers or masters. Colleagues from the Northern and Eastern countries, like the younger Agardh, Carl Adolph’s son Jakob Georg Agardh (1813–1901), and Johan Erhart Areschoug (1811–1887) from Sweden, also contributed to Mediterranean phycology. Later, Johan Nordal Fischer Wille (1858–1924) from Norway, Edouard von Glinka Janczewski (1846–1918) from Poland and Andrej Sergeevicˇ Famincyn (1835–1918) from Russia (to name only some outstanding representatives), due to their relative isolation in their home countries, were again more keen on working together with the Western and Southern European botanists. The efforts of all of these specialists yielded an impressive survey of the marine flora and vegetation as well as the natural history of the species of this region. Knowledge of the Mediterranean biodiversity and comparison with scientific results gathered by North American colleagues from their southern seashores and the Caribbean enabled the European specialists to understand the rich material of collections that soon was to come from the foreign colonies in Africa, South East Asia, South America and the Pacific territories. This much broeadened insight, in turn, improved and deepened the general understanding of the Mediterranean biota. In another contribution (Mollenhauer 2004) I have summarized an important part of Mediterranean phycology up to the end of the 19th century. In the early 20th century, a considerable number of field stations and other research centers around the Mediterranean Sea were active. For phycologists, the small private establishment at the Cape d’Antibes in France (now part of the Muséum National d’Histoire Naturelle, Paris) is a classical one of special interest. It was founded by Thuret in 1857. Another station which played an important role in research on the Adriatic Sea was the Zoologische Station Triest of the University of Vienna, founded in 1898 and closed after World War I in 1919. The director was Carl Cori (1865–1954). Among the institutions that were destined to grow were two rather special German foundations, viz. the Zoologische Station Neapel (now “Stazione Zoologica Anton Dohrn, Napoli”, founded in 1872) by Anton Dohrn (1840–1909), and the former Zoologische Station des Berliner Aquariums in Rovigno, (now “Institut za
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biologiju mora Rovinj”/Marine research station at Rovinj, Croatia; founded about 20 years later, in 1891). The latter was founded by Otto Hermes (1838–1910), then director of the Aquarium Unter den Linden in Berlin. Of course, there was some mutual influence among these stations. Fantini (2002: 7) reports how, after a visit to the Aquarium in the Prussian Capital, the idea occurred to Dohrn to combine a laboratory with a public aquarium so as to raise funds for the salary of a research assistant from the expected entrance fees. Both stations flourished thanks to the idealism and skillful management of their founders. However, for political reasons around the troubled times of World War I and soon after the founders had died, both institutions had to undergo severe alterations and “metamorphoses”, at least in terms of their organizational structure. But even before the cataclysms of World War I had brought so many changes in their wake, both stations were in permanent need of funds and sponsors. In order to raise the funds necessary for the continuation of work in Rovigno and Naples, scientific and other supporters had to do their utmost in rallying the financial support of the influential and moneyed (Partsch 1979). The research facilities offered by the aforementioned institutions enabled many phycologists to
study algae in the field and in labs situated in close proximity to the sea shore. This naturalist’s work done by scientists from many countries yielded a rather good survey of the structure, reproduction and growth conditions of many species. One exemplary summary of long-term work are Funk’s papers on the algae of the Gulf of Naples (Funk 1922, 1927, 1955). Further research was based on this knowledge of the natural history of the Mediterranean algae.
Experimental Studies The changing aspects of papers dealing with some special algae reflect the current concepts and ideas of botany in the late phase of natural history and the early years of experimental science. It is rather impressive to trace this way of studying a special organism under changing aspects. The siphoneous green algae Valonia and Halicystis are good examples. In spite of the similar aspects they are not narrowly related to one another. During a starting period of phycology characterized by exploration and inventories, the Italian naturalist, Giuseppe Conte Ginanni (1692–1753), described the algal genus Valonia in an opus posthumum (Ginanni 1755 [or 1757, according to Tilden 1937: 419]). This genus com-
Figure 1. The public aquarium of the Stazione Zoologica Anton Dohrn in Naples. In his autobiography, Anton Dohrn recollected “In Berlin I had time to visit the rather new Aquarium whose director was Dr. Brehm, whom I already knew. As I sat in thought and the carriage slowly climbed the rising road, I suddenly had an idea. The Zoological Station could be realized if one built a large aquarium on the Mediterranean, the richest sea in Europe, and use its proceeds to cover the coasts of a small laboratory” (Heuss 1991: 89).
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
prises several Mediterranean species (V. aegagropila, V. macrophysa, V. utricularis). The most impressing species forms green iridescent balloon-like cells that grow on the substratum. In some sites they grow in densely packed mats of aggregated vesicles resembling a pavement. Oltmanns (1922: 363) calls this alga “famous”. He refers to classic papers by C. A. Agardh, Famincyn, Schmitz and Kuckuck. These authors have analyzed the structure and reproduction of Valonia, especially the very strange type of cell division. Up to this day, the life history of Valonia is still under debate. There are reports of biflagellated gametes and indictions of a haplobiontic life cycle. After Greville’s introduction of the term “siphoneous”, the bladders of Valonia came to be understood as the largest examples of this vesicular type of thallus organization (non-segmented). Later, after the establishment of the cell theory and with a better understanding of the elements of cellular organization they were considered, together with the stem cells of the charophytes as ideal examples of giant multinuclear plant cells. Current knowledge of these organisms suggests that they should not be characterized as siphoneous algae. Their organization is better described as siphonocladalean and they are affiliated to the following genera: Chamaedoris Montagne 1842 Dictyosph[a]eria Decaisne 1842 Microdictyon Decaisne 1841 Siphonocladus Schmitz 1878 Struvea Sonder 1845 These form the family Valoniaceae (as described by Oltmanns 1904). In all these exclusively marine genera the frond consists of a simple or branched coenocyte that lives attached to the substratum. Some species have a complex thallus differentiated into a main axis with branches. In Valonia, in particular, the large branched coenocyte forms short rhizoidal basal appendages. Species of this genus are widely distributed in tropical and subtropical seas. Valonia utricularis (Roth) C. A. Agardh is a wellknown species of this genus from the Mediterranean. The main part is simply a large bladder sometimes reaching a diameter of 10 cm. In 1988, Valonia ventricosa, a very much used experimental alga, became Ventricaria ventricosa (J. Agardh) Olsen et West (Olsen and West 1988). The word “siphoneous” is now considered a descriptive term just as the aforementioned term, siphonocladalean. In 1878, one of the pioneers, F. Schmitz, described a new genus, Siphonocladus, based on material from the sea near Athens. Its parent cells cleave into a large number of vesicles with
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a multiseriate arrangement. They form a thread-like aggregate that can be branched. This organisation became the model type to describe the thalli of many green algae among which the Cladophorales are the most prominent. Round (1965: 37) turns our attention to the early observations by the younger Agardh and Nägeli. They had already noticed striations in the walls of these algae. This observation led to further studies, and eventually Valonia (Ventricaria) bladders became highly appreciated experimental organisms used in studies on wall-structure, wound-healing, permeability and absorption of electrolytes (e.g. Sugiyama et al. 2000, Bisson and Beilby 2002 – to name only two recent examples of papers dealing with this alga). Peter Kornmann (1907–1993) who later became famous for his studies on the life cycles of many benthic microalgae on the island of Helgoland, started his career as a young research assistant studying osmotic phenomena in Valonia cells in his home city Frankfurt am Main (Kornmann 1934). This particular interest led to several sojourns (1930, 1933, 1934) he made as a student and guest worker in the Stazione Zoologica in Naples. After working with Valonia, Kornmann planned further experiments and looked for similar algal material that was available in Central Europe. Thus he turned to the former Valonia ovalis (Lyngbye) J. G. Agardh which had been renamed after J. E. Areschoug’s creation of the new genus Halicystis in 1850. The new nomenclatural combination was called Halicystis ovalis (Lyngbye) Areschoug. At the first glance nomenclatural recombinations of this kind make the impression of rather arbitrary acts of taxonomists. Careful consideration of the reasons behind the creation of a new taxon Halicystis, however, rapidly does away with such hasty judgment. In spite of the significant similarity of Valonia and Halicystis Areschoug found their ways of reproduction rather different. Oltmanns who was not in favor of the creation of Halicystis (Oltmanns 1922: 305–306) nevertheless had to admit that the formation of swarmers occurs in a peculiar way. Without the formation of a true wall, the cell contents accumulate in the apical and/or subapical part of the bladder, then cleave into many biflagellate motile cells that are explosively released. On the other hand, George R. M. Murray (1858–1911) and Paul Kuckuck (1866–1918), supported Areschoug’s decision. Both were highly esteemed phycologists, their particular area of expertise having been materials from Northern seas as well as the Mediterranean. Kornmann successfully settled the case by corroboration of the positions of Areschoug, Murray and Kuckuck. Since Kornmann’s successful physio-
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logical research depended on the permanent supply of material of Halicystis, he began culture work. Eventually, he obtained the whole life cycle of this alga and could show that Halicystis is the gametophytic stage of the very dissimilar alga Derbesia, whose branched filametous thalli form the sporophyte (Kornmann 1938, see Lüning 1994). Thanks to this contribution, Kornmann gained the position of curator of botany on Helgoland. A mere substitute at first, he ended up staying for the rest of his life (except during wartime) on the island and successfully investigated many other such life cycles. Kornmann’s path to “maricultural breeding success” of Halicystis was prepared by the man whom he had replaced as botanist of the Biologische Anstalt Helgoland, Ernst Schreiber (1896–1980). Schreiber paved the way for the successful culturing of marine benthic and planktonic algae by introducing soil extract (for details see Mollenhauer and Lüning 1988). This new recipe was also well-known in Berlin-Dahlem, where Schreiber had hailed from originally. Two young biologists in the Kaiser-Wilhelm-Institut Joachim Hämmerling (1901–1980) and Bjørn Føyn (1898–1955) had successfully modified the Schreiber’s nutrient solution (Erdschreiber) and were able to culture marine algae in the laboratory. Max Hartmann (1876–1962), then director at the KaiserWilhelm-Institut für Biologie was head of the research group to which Hämmerling and Føyn belonged. Hartmann, his friend Fritz Schaudinn (1871–1906) and the third in this trio, Stanislaus von Prowazek (1875–1915), all three of them aspiring scientists, had been working for some time in the German [later: German-Italian] Marine Research Station in Rovigno (see Mollenhauer 1998, 2000; for Prowazek, who also had done research in Triest, see Jaenicke 2001). In 1910, the Kaiser-Wilhelm-Gesellschaft zur Förderung der Wissenschaften had taken over the management and funding of this station, which was to become an Italian one after World War I. After a longer interruption, the institution could continue research work after 1931 as a joint Italian-German foundation. Some years earlier, Ernst Küster (1874–1953) who visited the station at the same time when Hartmann and Prowazek were working there, had been most impressed by the inspiring hospitality and the facilities for living and investigations (see Steuer 1931, 1933; Küster-Winkelmann 1956: 126f; Zavodnik 1995).
A Man and “his” Alga: Joachim Hämmerling – The Acetabularia people Much later, Hartmann went again to the Adriatic Sea and became familiar with the genera Ectocarpus
and Acetabularia, the further study of which was to become research work on a very high level and with immense importance for general biology. Acetabularia, a member of the Dasycladales, is a “classical alga” which has long been a subject of scientific inquiry. The first adequate description was given in a 1750 monograph on the natural history of the Adriatic Sea by Vitaliano Donati (1711–1762). Donati gave its original name to the Callopilophorum, which later was to change to Acetabularia. The Spanish allround naturalist Antonio José [Joseph] Cavanilles (1745–1804) described the same organism under the name Corallina acetabulum thus showing that a definitive categorization of this organism had been long in coming. Dasycladales are probably the most popular fossil algae thanks to the work of Julius Pia (1887–1943). Paleobotanical research on these algae started rather early. The name Acetabularia was given by Lamouroux in 1812. For details of the early history, the fossil Dasycladales and cell research in general, compare the marvelous monograph by Sigrid Berger and Matthias J. Kaever (Berger and Kaever 1992). In 1929, Hartmann was again in the Mediterranean and collected Acetabularia, which he forwarded to Hämmerling. His coworker proceeded to culture it successfully. The latter also carefully studied the organization of the peculiar organism with a rhizoidal prostrate portion of the giant cell, the stalk and the “umbrella” which are already fully developed for several years before the alga is finally mature enough to reproduce. As is now common knowledge, there is during the vegetative stage only one giant nucleus of an impressive size up to a diameter of 80 µm. Hämmerling soon recognized “that there was a model system for studies on the role of the nucleus in the cell and the interactions of nucleus and cytoplasm.” ….. He “devoted all of his scientific life to exploring the physiological consequences of enucleation and nuclear transplantation in Acetabularia” (Berger 1996: 284). His scientific ardour had a profound impact on his family life: he and his family went to Naples in 1932 and collected material there; his wife Charlotte coauthored two of his papers. Seven years later, the couple spent several months in the Caribbean; and, in 1939, the family went to Rovigno where Hämmerling became German Director of the Institute of Marine Biology. Wherever he lived, he enlarged his collection of living strains of Dasycladales which he also managed to take with him after Mussolini’s downfall in 1943. After temporarily living at Langenargen on the Lake of Constance and working in an Institut für Seenforschung und Seenbewirtschaftung, he was able to move to Wilhelmshaven. There, the MaxPlanck-Gesellschaft (continuing and superseding
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
the Kaiser-Wilhelm-Gesellschaft) established something completely new: the Max-Planck-Institut für Meeresbiologie, founded in 1948 (Beth 1949, Schweiger 1969). Hämmerling went on with his investigations on Acetabularia until the day he retired. From this point onwards, Hans-Georg Schweiger (1927–1986), who next filled Hämmerling’s position, continued his predecessor’s work. Under his directorship the name of the institute was renamed MaxPlanck-Institut für Zellbiologie. The research group later moved to Ladenburg near Heidelberg. For many years, Acetabularia research was a matter of only the research group under Hämmerling. His persevering and consequent studies yielded the following main results: “The nucleus is the site where the genetic information is localized. – An anucleate cell is capable of performing morphological differentiation even though the nucleus contains the genetic information. – The nucleus delivers its information to the cytoplasm a longer time before it is needed. – The cytoplasm has the capability to store the genetic information and express it in a temporal sequence. – The cytoplasm also regulates nuclear activity. – The genetic information is polarly distributed in the cytoplasm. – The nucleus plays an important role in the establishment of polarity.” (cited from Berger 1996). Hämmerling’s work was never fully acknowledged by the scientific establishment. His research was not considered “big science”. But finally, additional groups shared his scientific program and/or supplemented it. Berger attributes the proliferation of Acetabularia research to some now well-known further authors (Bonotto, Brachet, Puiseux-Dao, Woodcock). Results obtained from the study of this very special alga paved the way for molecular biology. Numerous German botanists have contributed with at least one of their papers to Acetabularia research. The long list contains some names whose bearers are not generally considered Acetabularia people. Consequently, it seems fair to suggest that the scientific community has been influenced by Hämmerling’s personality and work to an extent that beg for a re-evaluation of his contribution to science. Some of Hämmerling’s cooperators, too, are/were rather modest and stayed in the background. Sigrid Berger was curator of the culture collection for many years. Her “horticultural care” was very successful. Whoever was lucky enough to see her beautifully green, healthy and thriving charges was deeply impressed. It is a special pleasure to know that the excellent collection of living Dasycladales-strains was transferred to Austin to be incorporated in the UTEX culture collection. Her and
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Kaever’s book is full of beautiful illustrations documenting her cultivated treasures. Another now almost forgotten scientist among the numerous and diverse Acetabularia people was Kurt Beth (1912–1999). He joined Hämmerling in Rovigno, following him also to Langenargen and Wilhelmshaven. Later, in 1956, he moved to Naples where he worked until his retirement. Beth wrote more than a dozen papers on Acetabularia. However, later he did marvelous work as the heart and soul of the Stazione Zoologica and care-taker of the archives, library and herbarium. He was one of these special people who were so integral and defining a part of many institutions in the old days, the decicated, educated all-rounders, who knew everybody and everything, in Beth’s case with the addition of his expertise on algae of the Gulf of Naples (Aliotta and Tripodi 2001). He deserves some lines of commemoration.
Relative Sexuality – Pure Research or Poor Research? Another alga that the Hartmann group introduced as an experimental organism is the brown intertidal alga Ectocarpus with branched uniseriate filamentous thalli. The definition of the genus was proposed by Lyngbye 1819. Before, these algae were categorized as so-called Conferva species. Numerous species have been described, though the definite boundaries between them remained obscure until today. These benthic algae are widespread in the upper littoral of cold to warm temperate regions of all oceans. Some species are true cosmopolitans. Taxonomic work with these algae is a rather unpleasant matter since species determination is unsuccessful in many cases (Kornmann and Sahling 1977: 91). However, by using pure cultures and considering carefully the modifying environmental factors, these difficulties can be overcome. Reproduction by motile spores from plurilocular sporangia was observed rather early, though later reports on the same phenomena and some different other modes of reproduction caused much confusion. An investigation of the complete life cycle by Dieter Gerhard Müller (*1935) was based on material of Ectocarpus siliculosus (Dillw.) Lyngb. from Naples (Müller 1967). These algae can be used as an experimental system for the study of reproduction and sexual behavior, speciation, biogeography etc. As early as 1935 Josephine E. Tilden (1869–1957) stated: “Perhaps no alga has been the subject of so much investigation as has Ectocarpus” (Tilden 1935: 238).
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Kuckuck and other authors who worked in the 1890s and 1910s started to revise the rather complex diversity of species and phenomena of reproduction. When Kuckuck died he left unfinished manuscripts whose editing was done later (Nienburg, Kornmann). Thus, taxonomy was improved step by step. In the 1880s Berthold worked in Naples on Ectocarpus siliculosus and saw the swarmers behaving as gametes, i.e. fusing. Berthold also made first cytological investigations. Later, Knight (1929) and Papenfuss (1935) incompletely confirmed the results obtained in Naples by Berthold with material from the Isle of Man and from Woods Hole, Massachusetts. D. G. Müller summarized the results of his thesis as follows: “The sexual life history involves two generations, which are connected by fertilization and meiosis: dioecious haploid gametophytes alternate with a diploid sporophyte of slightly different morphology. Sex determination is genotypic. The motile gametes are morphologically identical, but physiologically different, showing either male or female characters. Meiosis occurs in unilocular sporangia on diploid sporophytes. Several accessory reproductive pathways have been described. Unfertilized gametes develop into haploid sporophytes, which show two different types of reproduction: Plurilocular mito-sporangia perpetuate these genetically unisexual sporophytes, while zoids from unilocular sporangia can either re-establish the gametophyte phase, or develop into new unisexual sporophytes” (Müller 1988: 469). Hartmann’s interest in this alga was a very special one. He studied in a wide range of experiments the determination and differentiation of sex, sex substances and other phenomena in order to include these results into his general theory of sexuality (Hartmann 1943, 1956). Before, during and immediately after World War II he was a leading personality in German biology. However, several non-German books on biohistory on these years do not even mention Hartmann’s name. It seems that his dominance may have been a particular German affair. His somewhat obscure behavior in the awkward affair concerning Franz Moewus (1856–1937) may also have tainted his reputation (cf. Sapp 1990; Schnepf 2001). However, this is reflective only of Hartmann’s esteem outside Germany. In Germany itself, his work is still the basis of fundamental doctrines of biology and anthropology. Wolfgang Wickler (*1931) quotes his studies (without naming the author) in a popular survey of studies on the behavior of man and animals (Wickler 1969). Hartmann’s results are taken for incontestable facts. On the other hand, Annette Wilbois Coleman (*1934) comments on Hart-
mann’s Ectocarpus studies as follows: “A system of relative sexuality was proposed by Hartmann (1925) to explain some of the results he obtained with Ectocarpus siliculosus. This system differs empirically from multipolar breeding in that reactions between different strains are of differing, though constant, intensities. All strains can be classified in a linear array according to the intensity of their mating reaction, adjacent strains crossing weakly if at all. Hartmann’s theory has not been confirmed using pure cultures of any alga under constant conditions” (Coleman: 1962: 713f.). Similar reservation against Hartmann’s concept of relative sexuality can be found in a survey on algal sexuality by Gilbert Morgen Smith (1885–1959) written a few years after World War II (Smith 1951). Apart from that, Smith who was a leading phycologists in the USA. for had a very thorough knowledge of German research and held it in big esteem. Hartmann’s scientific heritage, his influence on biological doctrines and his special role during the “thousand-year Reich” are still a matter of vivid debate (Chen 2003).
Algae and Politics The last statement brings us back to the title of this paper. With the presented evidence in mind, it seems fair to suggest that research on algae forms a relationship of dependency with public opinion. What I mean by that is the observation that projects are supported or suppressed and selection of studied species, areas, and biota to be investigated are influenced by this factor. This dependency is mainly indirect, but not exclusively so. Availability of working facilities and accessibility to sites of collection and experiments is much more susceptible to politics. The “Nibelungentreue” [= faithfulness until death] connecting Imperial Germany and Imperial Austria before and during World War I hovered in the background of German research in the Adriatic Sea. The “Irredenta” [Italian nationalistic movement for uniting all Italian speaking people in one country] caused the heavy attacks by the Italians with which they aimed for the “liberation” of Triest/Trieste and the Eastern Adriatic coast from Austrian occupation. In consequence, work at the two research stations in Triest and Rovigno/Rovinj stopped altogether or was interrupted. The Stazione Zoologica in Naples was taken over by the Italian authorities from their German founders in World War II. However, some supporters of this world famous institution, in the first place Benedetto Croce (1866–1952), philosopher and politician,
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
brought about arrangements to continue work there and to further include the Germans in funding and research (Fantini 2002: 20). If we further think of personal suppression, holocaust, deportation, and internment, it becomes obvious that science as a matter supposedly kept safe in the haven of the much cited ivory tower never did exist in real life. It is mainly a matter of “unworldliness” of some scientists. Today, we approach everything, science as well as aspects of our personal lives, in terms of the economic value endeavors may or may not have. Marketing is going to govern scientific work. However, the relative value of culture, education and science should not only, or even mainly, be estimated by recourse to questions of expenditure and utility but rather with respect to more appropriate standards.
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Funk G (1955) Beiträge zur Kenntnis der Meeresalgen von Neapel, zugleich mikrophotographischer Atlas. Pubbl Staz Napoli 25 (Suppl) Ginanni G (1755) Opere postume (tomo I) nel quale si contengono 114 (Algae et Zoophyta) che vegetano nel more adriatico. Venezia. [The book was published in 1757, according to Tilden (1937): 419] Hartmann M (1925) Über relative Sexualität bei Ectocarpus siliculosus. Naturwissenschaften 13: 975–980 Hartmann M (1943, 1956) Die Sexualität, 1st and 2nd ed. G. Fischer, Jena, Stuttgart Hauck F ([1883–]1885) Die Meeresalgen Deutschlands und Österreichs. In Dr. L. Rabenhorst’s KryptogamenFlora, 2. Aufl. Kummer, Leipzig Heuss T (1991) Anton Dohrn – A Life for Science. Springer Verlag, Berlin, Heidelberg, New York
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Protist
FROM THE ARCHIVES
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia Dieter Mollenhauer1 Forschungsinstitut Senckenberg, Frankfurt am Main, Forschungsstation für Mittelgebirge, Lochmühle 2, 63599 Biebergemünd, Germany Kennst du das Land, wo die Zitronen blühn? [Do you know the land where lemons bloom?] Goethe: Lied der Mignon, Wilhelm Meisters theatralische Sendung, 4 (1)
Phycology on Tortuous Pathways In his magnificent two-volume “Structure and Reproduction of the Algae” Felix Eugen Fritsch (1879–1954) single-handedly provides us with his era’s ultimate summary of phycological knowledge. His works were published in 1935 and 1945, respectively. The two key words in the titles of Fritsch’s book are also appropriate to characterize the main trend of research in the period between 1850 and 1950. Algae were mainly studied to comprehend how they are organized and how this organization is brought about in the course of ontogenetic development. These organisms are particularly suited to provide one with an understanding of how growth results from cell division. In turn, comparative studies of cytokinesis yield insights into the phenomenon that the formation of new cellular walls and karyokinesis in algae, like in higher plants, can be linked although this is not a must (formation of siphoneous or siphonocladalean organization). Many general concepts of plant cytology and anatomy are derived from the study of algae. By giving the scientific Linnean name Fucus to the well-known littoral organisms living in the sea botanists also introduced the “model of an alga”. Thus, in early phycology, the “type seaweed”, i.e. kelp (in Britain and Scotland), varech [varec] (in France outside of Brittany), goémon (in Brittany, 1
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France), tang (in Nordic countries and Germany), became the standard of comparison for all other organisms whose character as algae was under debate. This is also the reason why brown algae in the early literature are collectively named Fucoideae C.A. Agardh (synonymous with Phaeosporeae Thuret, Melanospermeae Harvey and Melanophyceae Stizenberger). We are not sure whether “fucus” was really the name of an alga in GraecoRoman times. Moreover, looking for the understanding of the Latin word “fucus” or its Greek counterpart “ϕυ′κος” is of little help. In the end, the real meaning of “fucus” remains obscure, especially since it was seen as a type of beauty product rather than as a category of living beings. Initially, aquatic organisms other than Fucoideae were not named “algae”. Therefore, the older literature is full of notions like “conferva”, “lichen”, “muscus”, “tremella” or even “corallina”. Definitions of categories in biodiversity research are principally unstable since they always only reflect the status of current knowledge. If, in lucky cases, they are very precise, they are of the type of aphorisms, or better: epigrams. Consequently, in the field of biology, the need for flexibility reflective of the research progress on the one hand, and the need for stability for the purpose of systematic and nomenclatural orderliness on the other, are in permanent conflict. The biohistorian has to be aware of this fact and must 1434-4610/04/155/03-361 $ 30.00/0
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use current notions carefully when interpreting the past. What naturalists understood by algae changed thoroughly in the era of early inventories. Among the pioneers who brought together under a common name some of so many very dissimilar living beings and who defined the term “alga” in the first approaches were the early marine naturalists from the British Isles, France, Italy and Spain, and also some seasiders of other countries (Denmark, Germany – including those who then did service in Russia, the Netherlands, Sweden). The following list of names includes only some of many names: Adanson, C.A. Agardh, Bailey, Bivona, Bonnemaison, Bory de St. Vincent, Decaisne, De la Pylaie, Derbès, Dumortier, Fries, Ginnani, S.F. Gray, Greville, W.H. Harvey, Hering, Hooker, Hornemann, Kützing, Lamarck, Lamouroux, Link, Lyngbye, Meneghini, Montagne, O.F. Müller, Postels, Roth, Ruprecht, Solier, Sonder, Stackhouse, Zanardini. In the late 18th and early 19th centuries phycology is characterized by inventories (surveys of flora and vegetation) and more or less successful attempts to reconcile categories as unlike to each other as unicellular forms (infusoria), filamentous microphytes (Conferva), and large plant-like kelps. The study of ontogeny proved to be the most effective means by which to reveal relations that are not obvious if only the outer habit is compared. So, the different groups that finally were to form the Phaeophyceae were brought together by and by. This division was given the name we still use today as late as 1885 by Ferdinand Hauck (1845–1889). Before then the kelps and the filamentous brown algae were kept separate in different orders. As soon as phylogenetic thinking seized the whole of biology, matters were turned upside down. Now, the simple (early?) representatives of a group of presumably or obviously related organisms became the research subjects of special interest. Investigations concentrated on forerunners, ancestral forms, or whatever designations were given to organisms that were considered to be at the roots of a given line of evolutionary advance. This may be best illustrated by the study of sexuality, a study area which has fascinated biologists for centuries. For example, the final detection of the most fundamental process, i.e. fusion of two cells, male and female, can be clearly seen in algae. However, this interpretation of a very simple observation was only possible with an appropriate concept of sexuality. In algae, in special cases, two individuals formed by two single cells fuse to form the zygote. Thus, it is shown with all necessary clarity that sexuality and multiplication have to be kept separate in considering what reproduction of organisms means
and studying the ways how it is accomplished. This was the end of a very long discussion with many wrong turns and grotesque situations. Instead of useless speculation, observation of simple organisms clarified this matter. As we shall see, some marine algae were ideal for this purpose.
The Germans and Austrians and the Mediterranean – Two Extraterritorial Biological Stations Of course, Germany has seashores at both, the North Sea (sometimes still called “German Ocean”) and the Baltic. However, longing for and traveling to Italy (and the Mediterranean region in general) is a matter of German literary history. German speaking literary historians use the notion “topos” for such permanent feeling. Italian history, art, literature, landscape, fashion, wines, and cookery are in their entirety also a general concern of German culture (Waetzold 1927). Many Danish people are also fascinated by the Mediterranean and ever since the late 18th and in the 19th centuries haven been going there every year. During a rather long period in Central European history, only the ruling nobility, soldiers, pilgrims, tradesmen and traveling scholars were on the road. Educational journeys became popular in the 17th and 18th century. In the 19th century, financial conditions and the available means of public transport made tourism possible not only for the upper, but also for the middle classes of the society. To go and see the biota of the seashore, the high Alps and the Mediterranean, each of these at least once, became not only highly recommended but compulsory for all biologists. Many organisms from the South became especially well-known research objects and textbook cases of general botany. This was accomplished by intimate scientific cooperation and exchange of ideas between naturalists from the British Isles, Scandinavia, West, Central und East Central Europe on the one hand and those from Italy, and later, also from Spain and Greece on the other. In the field of phycology scientists from France, who had access to seashores in the North, West and South, played a special role. In many respects they acted as pioneers and trailblazers. Furthermore, biologists from the North liked to go themselves to the Mediterranean, and they still continue to do so. Nearly all botanists of high reputation in the 19th century spared neither effort nor expense to experience the Mediterranean nature. Topics and destinations of their travels varied, but the mainspring of all these journeys was the same. However, for the
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
French as well as for the Austrian colleagues the situation was different since the territories of both countries then included Mediterranean coasts. In the case of France this was the gorgeous landscape of the Côte d’Azur (or Riviera, as the Germans say with an Italian notion) and the further coastal area between Alpes Maritimes and Pyrénées. The Austro-Hungarian Empire had its “crownland” Triest (Trieste) and its coastland (“Küstenland”) in Dalmatia. Thus, to Austrians and Southern Germans, especially those living in Munich, the notion of “the Sea” denotes not so much the North Sea or the Baltic. The latter are only natural points of reference for Central and Northern Germans. By contrast, the seaside resorts the Bavarians and Austrians mostly think of are situated around the Adriatic Sea. These now well-established bonds between people and landscapes were established by the early travelers in the 18th and 19th centuries. Anyhow, many non-Mediterranean naturalists and scientists then traveled to the South. Among those who came early was our famous German poet Johann Wolfgang von Goethe (1749–1832) who went to Italy for three reasons: To escape trouble at the ducal court in Weimar, to study art and to experience the Southern nature. One of his admirers was the Swedish Carl Adolph Agardh (1785–1859) who followed the tracks of his idol in Italy and Bohemia in 1827 (Mollenhauer 2002). Friedrich Traugott Kützing (1807–1893) went to Italy mainly as a collector of plants. At that time many naturalists subscribed for exsiccata collections brought together by experienced botanists. The latter sold parts in advance (then called “Aktien”) and used the money to pay their own travel costs. Kützing, before obtaining a permanent position in Nordhausen, did so, too (Müller and Zaunick 1960). Nathanael Pringsheim (1823–1894) and Ferdinand Cohn (1828–1898) wanted to see Gustave-Adolphe Thuret (1817–1875) and/or his famous garden at Antibes which was a “Tusculum” as well as a destination for botanical pilgrimages (Cohn 1901). Ernst Haeckel (1834–1919) and his colleague in Jena, Eduard Strasburger (1844–1912), also liked to go to the Mediterranean. The Zurich people, Carl Nägeli (1817–1891) and Carl Cramer (1831–1901), Nägeli’s student and later the successor to his chair, saw Naples with Mount Vesuvius and the Amalfi coast, collected algae there and studied them on the collecting site and at home after returning to Zurich. Equally, the circles arount Anton de Bary (1831–1888) and Johannes Reinke (1849–1931), chose the same destination. The two leading personalities kept strictly apart. Their colleagues and students, however, did not join them in their “separatism”. Count Hermann zu Solms-
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Laubach (1842–1915), student and later successor of A. de Bary, also kept friendly relations and cooperated with Reinke when both were professors of botany in Göttingen. The others, Michael Woronin (1838–1903), Friedrich Schmitz (1850–1895), Gottfried Berthold (1854–1937), and Paul Falkenberg (1848–1925), were more exclusively associated with their respective teachers or masters. Colleagues from the Northern and Eastern countries, like the younger Agardh, Carl Adolph’s son Jakob Georg Agardh (1813–1901), and Johan Erhart Areschoug (1811–1887) from Sweden, also contributed to Mediterranean phycology. Later, Johan Nordal Fischer Wille (1858–1924) from Norway, Edouard von Glinka Janczewski (1846–1918) from Poland and Andrej Sergeevicˇ Famincyn (1835–1918) from Russia (to name only some outstanding representatives), due to their relative isolation in their home countries, were again more keen on working together with the Western and Southern European botanists. The efforts of all of these specialists yielded an impressive survey of the marine flora and vegetation as well as the natural history of the species of this region. Knowledge of the Mediterranean biodiversity and comparison with scientific results gathered by North American colleagues from their southern seashores and the Caribbean enabled the European specialists to understand the rich material of collections that soon was to come from the foreign colonies in Africa, South East Asia, South America and the Pacific territories. This much broeadened insight, in turn, improved and deepened the general understanding of the Mediterranean biota. In another contribution (Mollenhauer 2004) I have summarized an important part of Mediterranean phycology up to the end of the 19th century. In the early 20th century, a considerable number of field stations and other research centers around the Mediterranean Sea were active. For phycologists, the small private establishment at the Cape d’Antibes in France (now part of the Muséum National d’Histoire Naturelle, Paris) is a classical one of special interest. It was founded by Thuret in 1857. Another station which played an important role in research on the Adriatic Sea was the Zoologische Station Triest of the University of Vienna, founded in 1898 and closed after World War I in 1919. The director was Carl Cori (1865–1954). Among the institutions that were destined to grow were two rather special German foundations, viz. the Zoologische Station Neapel (now “Stazione Zoologica Anton Dohrn, Napoli”, founded in 1872) by Anton Dohrn (1840–1909), and the former Zoologische Station des Berliner Aquariums in Rovigno, (now “Institut za
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biologiju mora Rovinj”/Marine research station at Rovinj, Croatia; founded about 20 years later, in 1891). The latter was founded by Otto Hermes (1838–1910), then director of the Aquarium Unter den Linden in Berlin. Of course, there was some mutual influence among these stations. Fantini (2002: 7) reports how, after a visit to the Aquarium in the Prussian Capital, the idea occurred to Dohrn to combine a laboratory with a public aquarium so as to raise funds for the salary of a research assistant from the expected entrance fees. Both stations flourished thanks to the idealism and skillful management of their founders. However, for political reasons around the troubled times of World War I and soon after the founders had died, both institutions had to undergo severe alterations and “metamorphoses”, at least in terms of their organizational structure. But even before the cataclysms of World War I had brought so many changes in their wake, both stations were in permanent need of funds and sponsors. In order to raise the funds necessary for the continuation of work in Rovigno and Naples, scientific and other supporters had to do their utmost in rallying the financial support of the influential and moneyed (Partsch 1979). The research facilities offered by the aforementioned institutions enabled many phycologists to
study algae in the field and in labs situated in close proximity to the sea shore. This naturalist’s work done by scientists from many countries yielded a rather good survey of the structure, reproduction and growth conditions of many species. One exemplary summary of long-term work are Funk’s papers on the algae of the Gulf of Naples (Funk 1922, 1927, 1955). Further research was based on this knowledge of the natural history of the Mediterranean algae.
Experimental Studies The changing aspects of papers dealing with some special algae reflect the current concepts and ideas of botany in the late phase of natural history and the early years of experimental science. It is rather impressive to trace this way of studying a special organism under changing aspects. The siphoneous green algae Valonia and Halicystis are good examples. In spite of the similar aspects they are not narrowly related to one another. During a starting period of phycology characterized by exploration and inventories, the Italian naturalist, Giuseppe Conte Ginanni (1692–1753), described the algal genus Valonia in an opus posthumum (Ginanni 1755 [or 1757, according to Tilden 1937: 419]). This genus com-
Figure 1. The public aquarium of the Stazione Zoologica Anton Dohrn in Naples. In his autobiography, Anton Dohrn recollected “In Berlin I had time to visit the rather new Aquarium whose director was Dr. Brehm, whom I already knew. As I sat in thought and the carriage slowly climbed the rising road, I suddenly had an idea. The Zoological Station could be realized if one built a large aquarium on the Mediterranean, the richest sea in Europe, and use its proceeds to cover the coasts of a small laboratory” (Heuss 1991: 89).
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
prises several Mediterranean species (V. aegagropila, V. macrophysa, V. utricularis). The most impressing species forms green iridescent balloon-like cells that grow on the substratum. In some sites they grow in densely packed mats of aggregated vesicles resembling a pavement. Oltmanns (1922: 363) calls this alga “famous”. He refers to classic papers by C. A. Agardh, Famincyn, Schmitz and Kuckuck. These authors have analyzed the structure and reproduction of Valonia, especially the very strange type of cell division. Up to this day, the life history of Valonia is still under debate. There are reports of biflagellated gametes and indictions of a haplobiontic life cycle. After Greville’s introduction of the term “siphoneous”, the bladders of Valonia came to be understood as the largest examples of this vesicular type of thallus organization (non-segmented). Later, after the establishment of the cell theory and with a better understanding of the elements of cellular organization they were considered, together with the stem cells of the charophytes as ideal examples of giant multinuclear plant cells. Current knowledge of these organisms suggests that they should not be characterized as siphoneous algae. Their organization is better described as siphonocladalean and they are affiliated to the following genera: Chamaedoris Montagne 1842 Dictyosph[a]eria Decaisne 1842 Microdictyon Decaisne 1841 Siphonocladus Schmitz 1878 Struvea Sonder 1845 These form the family Valoniaceae (as described by Oltmanns 1904). In all these exclusively marine genera the frond consists of a simple or branched coenocyte that lives attached to the substratum. Some species have a complex thallus differentiated into a main axis with branches. In Valonia, in particular, the large branched coenocyte forms short rhizoidal basal appendages. Species of this genus are widely distributed in tropical and subtropical seas. Valonia utricularis (Roth) C. A. Agardh is a wellknown species of this genus from the Mediterranean. The main part is simply a large bladder sometimes reaching a diameter of 10 cm. In 1988, Valonia ventricosa, a very much used experimental alga, became Ventricaria ventricosa (J. Agardh) Olsen et West (Olsen and West 1988). The word “siphoneous” is now considered a descriptive term just as the aforementioned term, siphonocladalean. In 1878, one of the pioneers, F. Schmitz, described a new genus, Siphonocladus, based on material from the sea near Athens. Its parent cells cleave into a large number of vesicles with
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a multiseriate arrangement. They form a thread-like aggregate that can be branched. This organisation became the model type to describe the thalli of many green algae among which the Cladophorales are the most prominent. Round (1965: 37) turns our attention to the early observations by the younger Agardh and Nägeli. They had already noticed striations in the walls of these algae. This observation led to further studies, and eventually Valonia (Ventricaria) bladders became highly appreciated experimental organisms used in studies on wall-structure, wound-healing, permeability and absorption of electrolytes (e.g. Sugiyama et al. 2000, Bisson and Beilby 2002 – to name only two recent examples of papers dealing with this alga). Peter Kornmann (1907–1993) who later became famous for his studies on the life cycles of many benthic microalgae on the island of Helgoland, started his career as a young research assistant studying osmotic phenomena in Valonia cells in his home city Frankfurt am Main (Kornmann 1934). This particular interest led to several sojourns (1930, 1933, 1934) he made as a student and guest worker in the Stazione Zoologica in Naples. After working with Valonia, Kornmann planned further experiments and looked for similar algal material that was available in Central Europe. Thus he turned to the former Valonia ovalis (Lyngbye) J. G. Agardh which had been renamed after J. E. Areschoug’s creation of the new genus Halicystis in 1850. The new nomenclatural combination was called Halicystis ovalis (Lyngbye) Areschoug. At the first glance nomenclatural recombinations of this kind make the impression of rather arbitrary acts of taxonomists. Careful consideration of the reasons behind the creation of a new taxon Halicystis, however, rapidly does away with such hasty judgment. In spite of the significant similarity of Valonia and Halicystis Areschoug found their ways of reproduction rather different. Oltmanns who was not in favor of the creation of Halicystis (Oltmanns 1922: 305–306) nevertheless had to admit that the formation of swarmers occurs in a peculiar way. Without the formation of a true wall, the cell contents accumulate in the apical and/or subapical part of the bladder, then cleave into many biflagellate motile cells that are explosively released. On the other hand, George R. M. Murray (1858–1911) and Paul Kuckuck (1866–1918), supported Areschoug’s decision. Both were highly esteemed phycologists, their particular area of expertise having been materials from Northern seas as well as the Mediterranean. Kornmann successfully settled the case by corroboration of the positions of Areschoug, Murray and Kuckuck. Since Kornmann’s successful physio-
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logical research depended on the permanent supply of material of Halicystis, he began culture work. Eventually, he obtained the whole life cycle of this alga and could show that Halicystis is the gametophytic stage of the very dissimilar alga Derbesia, whose branched filametous thalli form the sporophyte (Kornmann 1938, see Lüning 1994). Thanks to this contribution, Kornmann gained the position of curator of botany on Helgoland. A mere substitute at first, he ended up staying for the rest of his life (except during wartime) on the island and successfully investigated many other such life cycles. Kornmann’s path to “maricultural breeding success” of Halicystis was prepared by the man whom he had replaced as botanist of the Biologische Anstalt Helgoland, Ernst Schreiber (1896–1980). Schreiber paved the way for the successful culturing of marine benthic and planktonic algae by introducing soil extract (for details see Mollenhauer and Lüning 1988). This new recipe was also well-known in Berlin-Dahlem, where Schreiber had hailed from originally. Two young biologists in the Kaiser-Wilhelm-Institut Joachim Hämmerling (1901–1980) and Bjørn Føyn (1898–1955) had successfully modified the Schreiber’s nutrient solution (Erdschreiber) and were able to culture marine algae in the laboratory. Max Hartmann (1876–1962), then director at the KaiserWilhelm-Institut für Biologie was head of the research group to which Hämmerling and Føyn belonged. Hartmann, his friend Fritz Schaudinn (1871–1906) and the third in this trio, Stanislaus von Prowazek (1875–1915), all three of them aspiring scientists, had been working for some time in the German [later: German-Italian] Marine Research Station in Rovigno (see Mollenhauer 1998, 2000; for Prowazek, who also had done research in Triest, see Jaenicke 2001). In 1910, the Kaiser-Wilhelm-Gesellschaft zur Förderung der Wissenschaften had taken over the management and funding of this station, which was to become an Italian one after World War I. After a longer interruption, the institution could continue research work after 1931 as a joint Italian-German foundation. Some years earlier, Ernst Küster (1874–1953) who visited the station at the same time when Hartmann and Prowazek were working there, had been most impressed by the inspiring hospitality and the facilities for living and investigations (see Steuer 1931, 1933; Küster-Winkelmann 1956: 126f; Zavodnik 1995).
A Man and “his” Alga: Joachim Hämmerling – The Acetabularia people Much later, Hartmann went again to the Adriatic Sea and became familiar with the genera Ectocarpus
and Acetabularia, the further study of which was to become research work on a very high level and with immense importance for general biology. Acetabularia, a member of the Dasycladales, is a “classical alga” which has long been a subject of scientific inquiry. The first adequate description was given in a 1750 monograph on the natural history of the Adriatic Sea by Vitaliano Donati (1711–1762). Donati gave its original name to the Callopilophorum, which later was to change to Acetabularia. The Spanish allround naturalist Antonio José [Joseph] Cavanilles (1745–1804) described the same organism under the name Corallina acetabulum thus showing that a definitive categorization of this organism had been long in coming. Dasycladales are probably the most popular fossil algae thanks to the work of Julius Pia (1887–1943). Paleobotanical research on these algae started rather early. The name Acetabularia was given by Lamouroux in 1812. For details of the early history, the fossil Dasycladales and cell research in general, compare the marvelous monograph by Sigrid Berger and Matthias J. Kaever (Berger and Kaever 1992). In 1929, Hartmann was again in the Mediterranean and collected Acetabularia, which he forwarded to Hämmerling. His coworker proceeded to culture it successfully. The latter also carefully studied the organization of the peculiar organism with a rhizoidal prostrate portion of the giant cell, the stalk and the “umbrella” which are already fully developed for several years before the alga is finally mature enough to reproduce. As is now common knowledge, there is during the vegetative stage only one giant nucleus of an impressive size up to a diameter of 80 µm. Hämmerling soon recognized “that there was a model system for studies on the role of the nucleus in the cell and the interactions of nucleus and cytoplasm.” ….. He “devoted all of his scientific life to exploring the physiological consequences of enucleation and nuclear transplantation in Acetabularia” (Berger 1996: 284). His scientific ardour had a profound impact on his family life: he and his family went to Naples in 1932 and collected material there; his wife Charlotte coauthored two of his papers. Seven years later, the couple spent several months in the Caribbean; and, in 1939, the family went to Rovigno where Hämmerling became German Director of the Institute of Marine Biology. Wherever he lived, he enlarged his collection of living strains of Dasycladales which he also managed to take with him after Mussolini’s downfall in 1943. After temporarily living at Langenargen on the Lake of Constance and working in an Institut für Seenforschung und Seenbewirtschaftung, he was able to move to Wilhelmshaven. There, the MaxPlanck-Gesellschaft (continuing and superseding
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
the Kaiser-Wilhelm-Gesellschaft) established something completely new: the Max-Planck-Institut für Meeresbiologie, founded in 1948 (Beth 1949, Schweiger 1969). Hämmerling went on with his investigations on Acetabularia until the day he retired. From this point onwards, Hans-Georg Schweiger (1927–1986), who next filled Hämmerling’s position, continued his predecessor’s work. Under his directorship the name of the institute was renamed MaxPlanck-Institut für Zellbiologie. The research group later moved to Ladenburg near Heidelberg. For many years, Acetabularia research was a matter of only the research group under Hämmerling. His persevering and consequent studies yielded the following main results: “The nucleus is the site where the genetic information is localized. – An anucleate cell is capable of performing morphological differentiation even though the nucleus contains the genetic information. – The nucleus delivers its information to the cytoplasm a longer time before it is needed. – The cytoplasm has the capability to store the genetic information and express it in a temporal sequence. – The cytoplasm also regulates nuclear activity. – The genetic information is polarly distributed in the cytoplasm. – The nucleus plays an important role in the establishment of polarity.” (cited from Berger 1996). Hämmerling’s work was never fully acknowledged by the scientific establishment. His research was not considered “big science”. But finally, additional groups shared his scientific program and/or supplemented it. Berger attributes the proliferation of Acetabularia research to some now well-known further authors (Bonotto, Brachet, Puiseux-Dao, Woodcock). Results obtained from the study of this very special alga paved the way for molecular biology. Numerous German botanists have contributed with at least one of their papers to Acetabularia research. The long list contains some names whose bearers are not generally considered Acetabularia people. Consequently, it seems fair to suggest that the scientific community has been influenced by Hämmerling’s personality and work to an extent that beg for a re-evaluation of his contribution to science. Some of Hämmerling’s cooperators, too, are/were rather modest and stayed in the background. Sigrid Berger was curator of the culture collection for many years. Her “horticultural care” was very successful. Whoever was lucky enough to see her beautifully green, healthy and thriving charges was deeply impressed. It is a special pleasure to know that the excellent collection of living Dasycladales-strains was transferred to Austin to be incorporated in the UTEX culture collection. Her and
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Kaever’s book is full of beautiful illustrations documenting her cultivated treasures. Another now almost forgotten scientist among the numerous and diverse Acetabularia people was Kurt Beth (1912–1999). He joined Hämmerling in Rovigno, following him also to Langenargen and Wilhelmshaven. Later, in 1956, he moved to Naples where he worked until his retirement. Beth wrote more than a dozen papers on Acetabularia. However, later he did marvelous work as the heart and soul of the Stazione Zoologica and care-taker of the archives, library and herbarium. He was one of these special people who were so integral and defining a part of many institutions in the old days, the decicated, educated all-rounders, who knew everybody and everything, in Beth’s case with the addition of his expertise on algae of the Gulf of Naples (Aliotta and Tripodi 2001). He deserves some lines of commemoration.
Relative Sexuality – Pure Research or Poor Research? Another alga that the Hartmann group introduced as an experimental organism is the brown intertidal alga Ectocarpus with branched uniseriate filamentous thalli. The definition of the genus was proposed by Lyngbye 1819. Before, these algae were categorized as so-called Conferva species. Numerous species have been described, though the definite boundaries between them remained obscure until today. These benthic algae are widespread in the upper littoral of cold to warm temperate regions of all oceans. Some species are true cosmopolitans. Taxonomic work with these algae is a rather unpleasant matter since species determination is unsuccessful in many cases (Kornmann and Sahling 1977: 91). However, by using pure cultures and considering carefully the modifying environmental factors, these difficulties can be overcome. Reproduction by motile spores from plurilocular sporangia was observed rather early, though later reports on the same phenomena and some different other modes of reproduction caused much confusion. An investigation of the complete life cycle by Dieter Gerhard Müller (*1935) was based on material of Ectocarpus siliculosus (Dillw.) Lyngb. from Naples (Müller 1967). These algae can be used as an experimental system for the study of reproduction and sexual behavior, speciation, biogeography etc. As early as 1935 Josephine E. Tilden (1869–1957) stated: “Perhaps no alga has been the subject of so much investigation as has Ectocarpus” (Tilden 1935: 238).
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Kuckuck and other authors who worked in the 1890s and 1910s started to revise the rather complex diversity of species and phenomena of reproduction. When Kuckuck died he left unfinished manuscripts whose editing was done later (Nienburg, Kornmann). Thus, taxonomy was improved step by step. In the 1880s Berthold worked in Naples on Ectocarpus siliculosus and saw the swarmers behaving as gametes, i.e. fusing. Berthold also made first cytological investigations. Later, Knight (1929) and Papenfuss (1935) incompletely confirmed the results obtained in Naples by Berthold with material from the Isle of Man and from Woods Hole, Massachusetts. D. G. Müller summarized the results of his thesis as follows: “The sexual life history involves two generations, which are connected by fertilization and meiosis: dioecious haploid gametophytes alternate with a diploid sporophyte of slightly different morphology. Sex determination is genotypic. The motile gametes are morphologically identical, but physiologically different, showing either male or female characters. Meiosis occurs in unilocular sporangia on diploid sporophytes. Several accessory reproductive pathways have been described. Unfertilized gametes develop into haploid sporophytes, which show two different types of reproduction: Plurilocular mito-sporangia perpetuate these genetically unisexual sporophytes, while zoids from unilocular sporangia can either re-establish the gametophyte phase, or develop into new unisexual sporophytes” (Müller 1988: 469). Hartmann’s interest in this alga was a very special one. He studied in a wide range of experiments the determination and differentiation of sex, sex substances and other phenomena in order to include these results into his general theory of sexuality (Hartmann 1943, 1956). Before, during and immediately after World War II he was a leading personality in German biology. However, several non-German books on biohistory on these years do not even mention Hartmann’s name. It seems that his dominance may have been a particular German affair. His somewhat obscure behavior in the awkward affair concerning Franz Moewus (1856–1937) may also have tainted his reputation (cf. Sapp 1990; Schnepf 2001). However, this is reflective only of Hartmann’s esteem outside Germany. In Germany itself, his work is still the basis of fundamental doctrines of biology and anthropology. Wolfgang Wickler (*1931) quotes his studies (without naming the author) in a popular survey of studies on the behavior of man and animals (Wickler 1969). Hartmann’s results are taken for incontestable facts. On the other hand, Annette Wilbois Coleman (*1934) comments on Hart-
mann’s Ectocarpus studies as follows: “A system of relative sexuality was proposed by Hartmann (1925) to explain some of the results he obtained with Ectocarpus siliculosus. This system differs empirically from multipolar breeding in that reactions between different strains are of differing, though constant, intensities. All strains can be classified in a linear array according to the intensity of their mating reaction, adjacent strains crossing weakly if at all. Hartmann’s theory has not been confirmed using pure cultures of any alga under constant conditions” (Coleman: 1962: 713f.). Similar reservation against Hartmann’s concept of relative sexuality can be found in a survey on algal sexuality by Gilbert Morgen Smith (1885–1959) written a few years after World War II (Smith 1951). Apart from that, Smith who was a leading phycologists in the USA. for had a very thorough knowledge of German research and held it in big esteem. Hartmann’s scientific heritage, his influence on biological doctrines and his special role during the “thousand-year Reich” are still a matter of vivid debate (Chen 2003).
Algae and Politics The last statement brings us back to the title of this paper. With the presented evidence in mind, it seems fair to suggest that research on algae forms a relationship of dependency with public opinion. What I mean by that is the observation that projects are supported or suppressed and selection of studied species, areas, and biota to be investigated are influenced by this factor. This dependency is mainly indirect, but not exclusively so. Availability of working facilities and accessibility to sites of collection and experiments is much more susceptible to politics. The “Nibelungentreue” [= faithfulness until death] connecting Imperial Germany and Imperial Austria before and during World War I hovered in the background of German research in the Adriatic Sea. The “Irredenta” [Italian nationalistic movement for uniting all Italian speaking people in one country] caused the heavy attacks by the Italians with which they aimed for the “liberation” of Triest/Trieste and the Eastern Adriatic coast from Austrian occupation. In consequence, work at the two research stations in Triest and Rovigno/Rovinj stopped altogether or was interrupted. The Stazione Zoologica in Naples was taken over by the Italian authorities from their German founders in World War II. However, some supporters of this world famous institution, in the first place Benedetto Croce (1866–1952), philosopher and politician,
International Politics, Ectocarpus, Valonia, Halicystis, and Acetabularia
brought about arrangements to continue work there and to further include the Germans in funding and research (Fantini 2002: 20). If we further think of personal suppression, holocaust, deportation, and internment, it becomes obvious that science as a matter supposedly kept safe in the haven of the much cited ivory tower never did exist in real life. It is mainly a matter of “unworldliness” of some scientists. Today, we approach everything, science as well as aspects of our personal lives, in terms of the economic value endeavors may or may not have. Marketing is going to govern scientific work. However, the relative value of culture, education and science should not only, or even mainly, be estimated by recourse to questions of expenditure and utility but rather with respect to more appropriate standards.
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Funk G (1955) Beiträge zur Kenntnis der Meeresalgen von Neapel, zugleich mikrophotographischer Atlas. Pubbl Staz Napoli 25 (Suppl) Ginanni G (1755) Opere postume (tomo I) nel quale si contengono 114 (Algae et Zoophyta) che vegetano nel more adriatico. Venezia. [The book was published in 1757, according to Tilden (1937): 419] Hartmann M (1925) Über relative Sexualität bei Ectocarpus siliculosus. Naturwissenschaften 13: 975–980 Hartmann M (1943, 1956) Die Sexualität, 1st and 2nd ed. G. Fischer, Jena, Stuttgart Hauck F ([1883–]1885) Die Meeresalgen Deutschlands und Österreichs. In Dr. L. Rabenhorst’s KryptogamenFlora, 2. Aufl. Kummer, Leipzig Heuss T (1991) Anton Dohrn – A Life for Science. Springer Verlag, Berlin, Heidelberg, New York
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