Adolf Seilacher (1925–2014) Palaeontologist Who Pioneered Analysis of Trace Fossils

COMMENT OBITUARY Adolf Seilacher (1925–2014) Palaeontologist who pioneered analysis of trace fossils.

dolf Seilacher used the simplest of that of a regular sea urchin, to show that not methods — careful observation — every shape has adaptive significance. to transform our understanding of Seilacher’s ability to interpret morphol- Aancient organisms. His interpretations of ogy from first principles is best demon-

the enigmatic Ediacara fossils, which date strated by his research on the strange fossils GERBER WOLFGANG from about 578 million years ago, before the of the Ediacaran period, with shapes such as appearance of the major animal phyla during fronds, spindles and discs. He saw in these the Cambrian explosion, explained forms “an exotic principle of organismic construc- found among the earliest large organisms. tion” consisting of quilted chambers that Seilacher also showed how trace fossils — maximize the surface available for feeding those that record biological activity such as and respiration. He assigned the Ediacara the burrowing of marine animals — reveal organisms to an extinct kingdom of life that behavioural traits. He analysed the influ- he called Vendobionta. The relationships of ences that shape invertebrate morphology these organisms remain controversial, but and showed how exceptionally preserved many examples investigated by Seilacher on fossil assemblages (for which he used the Mistaken Point in Newfoundland, Canada, term Lagerstätten) are the result of condi- show a fractal organization that defies easy tions such as low oxygen, rapid burial and assignment to any living group. the effect of microbial films that seal the Among the trace fossils, Seilacher was sediment surface. particularly fascinated by Paleodictyon, a In a career that straddled the Atlantic, regular, often hexagonal, mesh-like structure Seilacher influenced palaeontology as much that is connected to the sediment surface by with his personality as with his publications. short vertical tunnels, and occurs in rocks With a commanding yet engaging presence, from as far back as the Cambrian. Seilacher he had a way of asking questions that caught Otto Schindewolf discovered trilobite tracks interpreted this marine burrow as a ‘farm’ for speakers off guard — an occurrence referred in early Cambrian rocks, conveying clues raising bacteria. to as being ‘Dolfed’. about the animals’ lifestyle. In later years, In 1976, modern examples of Paleodictyon Seilacher, who died on 26 April aged 89, Seilacher’s advice was sought by oil compa- were discovered in the deep sea by ocean- was born in 1925 near Stuttgart in Germany. nies exploring sandstones in North Africa ographer Peter Rona. Almost 30 years later, He found his first fossil at the age of 14 and and the southwestern United States, because Seilacher and Rona boarded the submersible published his first paper, on fossil sharks he could use trace fossils to interpret the age vessel Alvin and retrieved samples from the from local rocks, at 18. He served in the and depositional environment of the rocks. Mid-Atlantic Ridge at a depth of 3.4 kilo German navy in the last years of the Second Seilacher spent much of his career at metres. Stephen Low’s 2003 film Volcanoes of World War before entering the University of Tübingen, retiring as a professor in 1990. the Deep Sea pictures the two of them slicing Tübingen in 1945. From 1987 to 2009 he spent autumns teaching soft sediments containing the burrow system There, palaeontologist Friedrich von at Yale University in New Haven, Connecti- — sadly, the animal proved elusive. Huene taught him to use the camera lucida, cut. In 1992, he was awarded the Crafoord An inveterate traveller, Dolf taught and an apparatus with a prism and mirror that Prize of the Royal Swedish Academy of Sci- did field work on every continent except projects the image of a specimen onto a sheet ences. This enabled him to travel the world, Antarctica. He collected not only fossils, but of paper so that it can be traced. Over the often with his wife, Edith, making replicas also rugs, ancient cylinder seals and pre- rest of his career, Seilacher made thousands of surfaces that preserve an extraordinary Columbian art, and loved to share stories of drawings in this way, both as illustrations range of trace and other fossils and sedimen- while enjoying a glass of wine and a cigar. He for his publications, and as an aid to under- tary structures such as ripples. This collection published works on an extraordinary range standing fossils. He favoured a portable cam- became his own international touring exhibi- of fossils over his 70-year career, notably his era lucida that once belonged to von Huene tion, entitled Fossil Art. 2007 text Trace Fossil Analysis (Springer) and rather than the modern versions that attach Seilacher’s insights fundamentally his forthcoming Morphodynamics (CRC to binocular microscopes. changed the analysis of the evolution of Press). Seilacher remained at Tübingen for his form. He broke away from the prevailing His iconic drawings and interpretations doctorate to study Jurassic and Triassic idea that all morphological features are will remain inspirational for teachers and trace fossils (dating from about 252 million adaptations for some function. He mined students for years to come. ■ to 145 million years ago). He spent time collections, particularly those of the Pea- at the Senckenberg marine station on the body Museum of Natural History at Yale, Derek E. G. Briggs is director of the Baltic Sea, where he learned ‘actuopalae- for convergent morphologies that provided Peabody Museum of Natural History at ontology’ — using the behaviour of living evidence of other influences. No Seilacher Yale University in New Haven, Connecticut, organisms as a guide to interpreting fossils. course on invertebrates was complete with- USA. He taught with Dolf Seilacher at Yale In 1951, on an expedition to the Salt Range out his demonstration that a water-filled bal- from 2003 to 2009. in Pakistan, Seilacher and his PhD adviser loon automatically assumes a form similar to e-mail: [email protected]