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Proteus: How Radiolarians Saved Ernst Haeckel

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Ernst Haeckel around Christmas 1860, when he was 26, the year after he returned from Italy.

Ernst Haeckel had spent an unhappy year practicing medicine when his parents finally consented to pay for a year of scientific study and travel in Italy. It was 1859, and he was 25. He had discovered a passion for biology and a talent for art during his college years, but his parents had pushed for practicality. If there was ever an antidote for practicality, it's Italy.

Once there, the lure of the lush Neapolitan landscape and hot weather that pushed the ocean microbes he'd hope to study far north conspired to draw the young scientist toward landscape painting. He was finding very little in his ocean samples, and began to lose faith that he had a talent for science. As he spent weeks living with other artists and enjoying the perks of the non-starving artists' lifestyle, he seriously pondered leaving science for good.


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Then he traveled to Messina, Sicily, where ocean currents and the geometry of the harbor captured tiny ocean protists called radiolarians in abundance. Haeckel was enchanted. Science had him. But so did art -- he would go on to paint or draw thousands of radiolarians and scores of every other sort of living creature known to 19th century science.

This the crux of the story told in the documentary "Proteus", the 22-year labor of love of filmmaker David Lebrun, which I have long known about as an ardent fan of Haeckel's art and had long planned to see. This week I finally did. I approached it with trepidation because although the IMDB reviews were favorable, the reviews at Netflix were decidedly not.

Here are a few clips to give you a taste:

What was it he saw in the radiolarians that drew Haeckel back to science? "Every morning I am newly amazed at the inexhaustible richness of these tiny and delicate structures," he wrote. "That I thrust myself with sheer passion on these scientific treasures, which are simultaneously so pleasing to the aesthetic eye, you can well imagine." Haeckel had two passions. Radiolarians satisfied both.

Radiolaria with algal symbionts inside. By, of course, Haeckel.

Radiolarians are tiny protists that live inside intricate silica shells. Because silica is impervious to the acids that often dissolve shells made of calcium carbonate at great depth, they make up a huge proportion of the sludge found on deep sea beds. They extend tiny pseudopods out from their shell to capture food, and sometimes they house algae to help feed them.

They were among the earliest eukaryotes to evolve at the end of the Pre-Cambrian, 550 million years ago, and their shells have varied so much over time that they are useful for dating petroleum beds and geological formations. But why do they have those shells, and what force could be selecting for the endless variety in their structure? I do not know.

The film describes how Haeckel, raised a Christian, was torn as a youth between two powerful forces: his love of science, which seemed to be reducing nature to a system of soulless laws, and his love for the romanticism of the early 19th century German philosophers. That included, in particular, Goethe, who believed that (I'm, obviously, paraphrasing here) God is not a discrete being, but is found as an ineffable and intangible presence in all parts of nature, no matter how tiny -- the "God in Nature". Radiolarians, filmmaker David Lebrun argues, were what first resolved the tension in Haeckel between those two conflicting forces. In their endless variety and enchanting beauty, Haeckel felt he was seeing and touching -- and by drawing them, sharing -- a part of God.

Later in Haeckel's life, the Challenger expedition dredged up thousands of new deep-sea radiolarian species from the depths of the Mariana Trench, site of Challenger Deep, the deepest spot on Earth, some five miles beneath the surface. Haeckel spent a decade studying the sediments brought back by the expedition and drawing the 3,000 new species he found, and it is these images that you see flipping by in black and white in "Proteus", by director David Lebrun.

On nights and weekends over two decades while he often supported a family with other jobs, Lebrun labored to bring this film to the screen. He commissioned an original score and spent thousands of hours photographing Haeckel's work (today with digital technology the same work would take only a few days).The film is illustrated like a Ken Burns film exclusively with beautiful period artwork, and whoever was the foley artist deserves a gold star: the sound effects bring them alive.

Lebrun likes to play with repetition of pattern, but I felt that the radiolarian animation sequences would have better achieved the point he was trying to make much better if he slowed down the switching of images a bit and never once repeated one. From watching bonus material, I know his goal was to make the radiolarians appear to dance. But I found it distracting and, strangely, almost boring after a certain point, and felt it got in the way of the point he was trying to make. Considering that Haeckel drew thousands of radiolarians, there was no need to repeat. If I'd never seen the same radiolarian twice, I think I would have felt more awe.

Although the reviewers on Netflix complained that the film was boring and repetitive, I found it to be engrossing, beautiful to look at and listen to (if a bit slow at times), and completely coherent. Lebrun does a great job tracing the historical, scientific, and literary forces that shaped Haeckel's world, from the influence on romantics of Samuel Taylor Coleridge's Rime of the Ancient Mariner, to the unexpected spur to oceanography that the laying of the first trans-Atlantic telegraph cable by the SS Great Eastern proved to be. At one point, it even moved me to tears. I recommend.

More radiolaria, again by Haeckel. Notice icosahedral structures at top that evolved convergently with some virus capsids.

Though Haeckel went on to become one of the most influential and widely-read biologists of the 19th century, championing evolutionary theory, drawing the first evolutionary tree to incorporate all known life, coining the terms phylum", "phylogeny", "ecology", and "protist", and being among the first to boldly, publicly, state that humans evolved from apes and life evolved from non-living matter, he embraced some controversial, and in several cases, incorrect theories about evolution. Perhaps as a result, he is little known today.

Probably his biggest blunder was his belief in Recapitulation Theory, often expressed as "ontogeny recapitulates phylogeny". He believed the embryonic forms of animals literally expressed their evolutionary history, and that humans pass through all the stages of their past evolution as embryos. This is not correct; at best, we might say that embryos pass through many, but not all, of the embryonic forms of our ancestors, but certainly not their adult forms.

Instead of natural selection, he also believed a form of Lamarckism was the driver of evolution. He also succumbed to racial prejudices common during his time and used science to back his views, sullying his reputation today, and he held controversial and mystical religious ideas that drew attacks from contemporary scientists and clergy alike.

"Everything now came before me in new and beautiful and remarkable forms," he wrote of the radiolarians in Messina. "I began to see and hear not only the outer forms, but also the inner content, the nature and the history of things." The astute reader will recognize this as an early expression of his Goethe-driven mystical nature philosophy as well as ultimately flawed belief in Recapitulation Theory.

But he had this virtue: an unadulterated sense of wonder at the diversity of life, and a burning passion to share this wonder with others through his art. Indeed, he believed the universe was an infinite unfolding work of art, and that it was a scientist's job to portray with both precision and passion what he had found.


If his personal philosophy led him astray scientifically, the romantic artist in him was able to depict the diversity of life in a way so moving that it is alluring to non-scientists even today. Personally, I will never get enough of Haeckel's art, which helped inspire my beloved Art Nouveau. I've seriously considered decorating a room, or possibly every room, in my house with them.

Indeed, I'm not the first person with this impulse. Lebrun discovered during his research that Haeckel's home in Jena, Germany -- the aptly named Villa Medusa -- was adorned with such features as chairs carved with radiolarians and a chandelier surrounded by a painted jellyfish mandala. WANT.

You can buy a copy of his 1904 masterwork "Artforms of Nature" here at Amazon, originally issued in 10 sets of 10 between 1899 and 1904, of which at least one print in almost every set was of radiolarians. Or you can buy individual prints of them to hang on your wall here (or just search for "Haeckel" at your favorite art prints webseller). And if you're interested in "Proteus" and don't have Netflix or similar, look for it at Amazon.

Whatever his faults as a scientist and biologist, to me his legacy as science illustrator is his highest and greatest. In my opinion, the best science communicators -- Carl Sagan, Richard Feynman, Rachel Carson, or Jane Goodall, to pick a few -- understand that speaking to people's hearts about science is as important as speaking to their brains. In this mission, I believe Haeckel was an unqualified success.

What was it he saw in the radiolarians that drew Haeckel back to science? "Every morning I am newly amazed at the inexhaustible richness of these tiny and delicate structures," he wrote. "That I thrust myself with sheer passion on these scientific treasures, which are simultaneously so pleasing to the aesthetic eye, you can well imagine." Haeckel had two passions. Radiolarians satisfied both.