Michael Sars

Michael Sars: The Vicar Who Emptied the Azoic Zone

In 1864 a dredge worked off the Lofoten Islands came up carrying a stalked crinoid — a sea lily on a slender column, an animal European science had catalogued almost entirely from fossil beds. Michael Sars, by then professor of zoology at Christiania and past his sixtieth year, described it as *Rhizocrinus lofotensis*. It had been raised from roughly 300 fathoms, some 1,800 feet down, in water the leading naturalists of the day held to be lifeless. The specimen was small, pale and unspectacular. It also helped end one of the nineteenth century's more confident errors.

From a Bergen Wharf to the Theology Lecture Hall

Sars was born in Bergen on 30 August 1805, into a household with the sea already in it: his father was a sea captain and merchant of Bremen origin, his mother Divert Henriche Heilmann, of partly Estonian descent. Norway in the 1820s offered a bright young man few professional routes, and Sars took the standard one. He read theology at the Royal Frederick University in Christiania and took his candidate's degree in 1828. Nothing in that training pointed toward invertebrate zoology. What decided him was geography — the country he was about to be posted to.

Twenty-Six Years in a Coastal Parish

Between 1828 and 1854 Sars worked as teacher, vicar and rector in coastal Norwegian communities. The job required constant travel by boat between scattered congregations, and Sars turned every crossing into a collecting trip. The fjords were his laboratory: deep, cold, unusually accessible from shore, and almost entirely undescribed. He worked without a university appointment, without a research budget, and without colleagues within easy reach, publishing in Norwegian — a scientific language the rest of Europe largely could not read. He married Maren Welhaven in 1831; the household eventually ran to fourteen children.

This is the least glamorous and most important stretch of his career. Between roughly 1830 and 1860 he did the observational work that made his name — not in a single heroic expedition, but in thousands of hours of patient watching of animals he could keep alive in front of him.

What a Jellyfish Actually Is

Sars's first great result concerned identity. Nineteenth-century marine catalogues were clogged with organisms named as separate species on the strength of a single look. Sars recognised that many of them were not species at all but stages: the same animal at different points of its life, wearing forms so unlike each other that nobody had thought to connect them.

His most celebrated case was the jellyfish. He identified the sessile stage — the small stalked polyp fixed to the seabed — as the same creature as the free-swimming medusa, work that fed directly into the study of alternation of generations. He did comparable work on molluscs and other invertebrates, describing larval forms including the trochophore and the veliger, now standard fixtures of any zoology syllabus and then genuinely unknown quantities.

The intellectual move is worth naming precisely: Sars stopped treating a marine specimen as a fixed thing to be filed, and started treating it as a moment in a trajectory. Almost everything else he did followed from that habit.

Emptying the Azoic Zone

The other orthodoxy he broke belonged to Edward Forbes, whose azoic hypothesis held that animal life gave out below roughly 300 fathoms and that beneath that line the ocean was a dead zone. It was tidy, plausible and wrong, and the deep-water fjords of Norway happened to be one of the best places on earth to prove it wrong.

Sars dredged. He documented taxa living well past 450 fathoms, and in 1864, working with his son Georg Ossian, brought up the living sea lily from the Lofoten deeps. A living stalked crinoid was more than one more record: it suggested the deep sea might be holding fauna the fossil record had written off, and it made the ocean floor look less like a desert than like an unexplored continent. The find was noticed everywhere. Sars argued publicly for international deep-sea expeditions, and the enthusiasm his crinoid generated fed into the voyage of HMS *Challenger* in the 1870s — the cruise from which modern oceanography is usually dated.

The Chair, at Last

The academic establishment came round slowly. Honorary doctorates arrived from Zurich in 1846 and Berlin in 1860; the Royal Swedish Academy of Sciences elected him in 1855. In 1854, aged forty-nine, he finally got a salaried scientific post: professor of zoology at the University of Christiania, which he held until his death in 1869. He published some ninety-five papers, most originally in Norwegian, and the World Register of Marine Species credits him with naming 260 marine species. His two large books were *Fauna littoralis Norvegiae* (two volumes, 1856), a survey of Norwegian invertebrates, and the *Mémoires pour servir à la connaissance des crinoïdes vivants* (1868), which put the living sea lilies on the record in plates.

The Norwegian parliament also set him to work on the biology of the fisheries — a question of national income, not curiosity. He did not live to finish it; Georg Ossian did.

Why Michael Is Called a Genius

The quality at work here is not speed, mathematical power or theoretical daring. It is a rare and specific kind of seeing. Sars looked at organisms other competent naturalists had already looked at and noticed that they were the same organism. That requires holding an animal's entire life cycle in mind as a hypothesis while you watch a tank for weeks, and being willing to conclude that the published catalogue — the collective work of your field — is partly an artefact of impatience. His attack on the azoic hypothesis has the same shape: he did not out-argue Forbes, he went and looked, in the one place on earth where looking would settle it.

The honest counter-case is that Sars was not a system-builder. He produced no general theory comparable to those of his great contemporaries, and much of his output is descriptive taxonomy of a kind the twentieth century learned to undervalue. He worked in a small language, and a good deal of his influence reached the wider world second-hand. His most famous single object, the Lofoten crinoid, was hauled up by his son. What can fairly be claimed is narrower and still large: he is routinely described as one of the fathers of marine zoology, and two of the founding facts of the discipline — that many marine species are life stages, and that the deep sea is inhabited — are his. Call it the genius of the patient observer, which is a real category and a scarce one.

Legacy

The Sars name became a scientific dynasty: his sons Georg Ossian and Ernst both became scholars of note, Georg Ossian carrying the marine work forward for another half-century. Norway named a research vessel *Michael Sars* in 1910, and the University of Bergen's Michael Sars Centre for marine molecular biology carries his name today, still working on the animals he first pulled out of the fjords. He spent twenty-six years as a parish clergyman and fifteen as a professor, and the ocean floor has not been thought empty since.

Achievements

• Held posts at University of Oslo
• Educated at Bergen Cathedral School and University of Oslo
• Fields of research: marine biology and zoology