Slime After Slime

On a dewy morning in July, I found a mysterious pile of yellow goo in my backyard. Initially, I wondered if my golden retriever, who will eat literally anything, was to blame. Upon closer inspection, I realized the mystery pile was indeed dog vomit, just not the kind I’d thought.

Turns out it was Fuligo septica, a species of slime mold known, fittingly, as dog vomit. Until then, I had never recognized slime mold in the wild but was able to identify it thanks to this issue’s Young Naturalists article (“Stranger than Science Fiction”) which the MCV staff was working on at the time. The story is all about the weird, surprisingly beautiful world of slime molds, a variety of small or microscopic organisms found mainly in damp, shady environments around the world.

To encounter slime in the wild while simultaneously working on an article about slime molds was a nifty bit of synchronicity. And it led me to learn more about Fuligo septica, which was first described by 18th-century French botanist Jean Marchant, who noticed it on tree bark and referred to it as fluer de tan, or bark flower. (In Finland, the slime was once believed to be used by witches to spoil their neighbors’ milk.)

Subsequent research has revealed all sorts of cool things about dog vomit. The slime has two life stages. First, it takes on a blob form and oozes over straw, wood, and other organic matter, hoovering up fungi, yeasts, and bacteria in its path. When it’s out of food, it fruits and releases spores that blow away to start the blobby process all over again. Due to Fuligo septica’s amoeba-like movements, researchers have used it as a model to study the behavior of cancer cells and to understand the evolution of RNA.

I hope you’re just as tickled about our slime mold article as I am. And who knows? Maybe we’ll get some damp, cool weather this fall and you’ll have your own slimy encounter. Happy hunting!