Category Archives: Protista

The Robot Farm

A slime mold is precisely the sort of thing you don’t want to step in. That also means figuratively, if you’re the kind of person who likes their taxonomy neat. That’s because slime molds aren’t molds at all… except for a few species that are. And while some of them are very slimy indeed, they usually aren’t. What?


The aptly-named Dog Vomit Slime Mold.

If not a fungus, usually, what is a slime mold? Either a giant amoeba, or a collection of amoebae. A plasmodial slime mold is essentially one giant cell with thousands of individual nuclei: a gross puddle of cytoplasm. But a cellular slime mold, my favorite kind, is a loose assembly of individual amoebae who, when a chemical signal is released, band together to form one creeping pile of neon goo that patrols the undergrowth, hunting for new bacteria for its component amoebae to munch, and creating a reproductive organism. For an analogy, imagine a herd of caribou on a wide open expanse of tundra, each browsing on lichen and moss by itself. But instead of migrating as a herd when they’ve finished off all the moss on the meadow, the caribou exude a pheromone that tells them to meet in the center and merge into one Super-Caribou that then takes off in search of more moss. Some caribou become the hooves, some the antlers. Some become the Super-Caribou’s testicles, producing sex cells for future use.


All the ones on the right are going to become the ears. The ones on the left… you don’t want to think about it.

Slime molds may not have antlers — or many discernible features at all, really — but they do have sex cells. Incredibly, some of the amoebae will sacrifice themselves to become the cells of the stalks that elevate the colony’s sori, or spore-producing organs, while others become the sex cells which will produce the spores themselves. In this way, the amoebae that make up a slime mold are like stem cells that act freely and independently of each other when feeding, then become differentiated when they join to become a multicellular organism. Like the Portuguese Man-of-War, it is an animal made of smaller animals, or more appropriately, a fungus-like thing made of smaller amoeba-like things.


Teamwork rhetoric aside, being the sex cells is a pretty highly coveted position among the amoebae.

But here’s the exciting part: it turns out that certain slime molds have developed agriculture. In a recent study, it was found that certain amoeba “cells” in Dictyostelium discoideum, a species of slime mold, could actually cultivate the very bacteria that the organism eats in its sori. That’s right: a brainless, de-centralized collection of unicellular organisms learned how to farm. If this doesn’t instantly impress you, think about how many other organisms out there purposefully cultivate their own food: it’s pretty much the leaf-cutter ants and us. Farming may not seem sexy to some people, but the difference between hunting-and-gathering and making your own nourishment where you live was a quantum leap made a mere ten thousand years ago that established human dominance over the Earth. Art, science, technology, and civilization itself came from the simple act of planting a seed.

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The Horror

January 5, 1929 — I have now fully resolved to kill Doctor Henry Moore, and a recent incident has shown me how I shall do it… A party from Uganda brought in a black with a queer illness which I can’t yet diagnose. He was lethargic, with a very low temperature, and shuffled in a peculiar way. Most of the others were afraid of him and said he was under some kind of witch-doctor spell; but Gobo, the interpreter, said he had been bitten by an insect. Spectral-looking — I don’t wonder the boys lay it to black magic. They seem to have seen cases like it before, and say there’s really nothing to do about it.
— H. P. Lovecraft, “Winged Death,” 1933

The Kingdom of Mali, 1375. It is the golden age of this African empire, with trade flourishing between its polar cities of Marrakesh and Timbuktu. Islam is growing here in Central Africa, due to a persuasive peace between local Central Africans and educated immigrant Arabs. But the kingdom is ruled by a cruel and arrogant despot, Sultan Diata II, whose lavish train of elephants, slaves, and golden carriages on his pilgrimage to Mecca made the continent gasp at his ostentatious display of wealth. Unfortunately for Diata, his days of opulence are numbered. The North African historian Ibn Khaldoun wrote that the Sultan “had been smitten with the sleeping sickness, which frequently affects the inhabitants of that region, especially the chieftains… Those afflicted are virtually never awake or alert. Sultan Diata had suffered for a duration of two years, after which, he died.”


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The Heavenly Zoo of Ernst Haeckel

If you asked who my favorite wildlife illustrator of all time is, the answer might surprise you. I wouldn’t choose Audubon, with his awkward flamingos, or Sibley with his scientific field guide portraiture, or even a modern master like Peter Schouten. (Twenty points if you can name this animal, regular readers!) No, my heart belongs to the proto-Art Nouveau stylings of a 19th century German naturalist who was all at once romantic, revolutionary, infuriating, misguided, and ultimately, necessary.

Ernst Haeckel was a zoologist, anatomist, and natural philosopher whose ideas shook the scientific world. He discovered the Kingdom of Protista, the eukaryotic microscopic organisms which contain the algae family and which, though still controversial, remains among biology’s “Fave Five.” While most naturalists are fortunate to discover a species or genus, and the occasional scientist discovers a phylum, it takes huge intellectual gonads to discover an entire Kingdom. Oh, he also invented the word and the idea of a “phylum.” Likewise, he also coined several other words indispensable to modern science, such as “phylogeny,” “anthropogeny,” and my favorite, “ecology.” He proposed that psychology was really a product of physiology — essentially, that one’s mind was a product of physical developments in the brain — which opened up, among other things, the modern disciplines of psychiatry and neurology. He floated the idea that the fossilized remains of human ancestors, which had not yet been discovered, would be found in Indonesia. His student, Eugene Dubois, took his advice and dug up the first Homo erectus: Java Man. And if that wasn’t enough, his Kunstformen der Natur singlehandedly redefined the art of wildlife illustrations.

Anemones:

Reptiles:

Hummingbirds:

Jellies:

That great medusa in the center he discovered and named Desmonema annasethe after his late wife, Anna Sethe. The flowing red tentacles reminded him of her ginger tresses. As I said, he was a Romantic.

It was Haeckel’s propensity toward the Romantic which clouded his otherwise brilliant scientific mind. He routinely hypothesized missing links and imaginary places — such as Lemuria — which would justify his evolutionary ideals. Though he was a friend, correspondent, and booster of Charles Darwin, he rejected the seemingly cruel theory of natural selection in favor of the more optimistic but outdated version of evolution called Lamarckism. He famously coined the phrase and theory “ontogeny recapitulates phylogeny” — in layman’s terms, that a fetus undergoes all the stages of evolution leading up to its ultimate development. The idea that a human fetus becomes, at various stages of development, a fish, a frog, a dog, and a monkey, is a sweet and tidy vision of evolution as a progressive journey toward an ultimate life form. It’s also wrong. That didn’t stop Haeckel from drastically altering his artwork to “prove” his confabulation.


Though it’s true that all vertebrates start out as gross little tadpole monsters.

The most disturbing aspect of his insistence on altering his science to fit his world view was his views on anthropogeny, the study of human origins. Why Haeckel agreed with Darwin that men were evolved from apelike ancestors, he didn’t believe that we were all evolved from the same apelike ancestor. In true German fashion, Haeckel believed that the races were essentially different species, with Germans being the “most evolved.” I don’t need to tell you who really cottoned to this idea.


But what’s really, really disturbing is how many pictures of Barack Obama turn up when you google “monkey hitler.”

So Ernst Haeckel was wrong as often as he was right, and usually in the extreme either way. His artwork shows almost everything you need to know about the man’s ideals; he was relentless in his endeavor to prove that nature was a place of order, balance, and beauty. And nowhere was this more evident than in his depictions of the protists he personally discovered: the radiolarians.

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