Mother Nature may be timeless, but some of her creations seem kind of, well, dated. Take bioluminescent fungi, for example: funky fluorescent figures that look like they popped right out of a blacklight poster from 1996. Check out the timelapse video below from Planet Earth II for more glowing weirdness and read on for an explanation (as much as something like glowing mushrooms can be explained).

Glowing mushrooms are not a new phenomenon. Both Aristotle and Pliny the Elder wrote of the “foxfire” produced by mushrooms on rotting logs. So far, scientists have discovered 81 different species of bioluminescent fungi. They appear across the globe and take all kinds of weird shapes, but they always emit the same eerie green light.

The precise purpose of that green light remains to be seen. Bioluminescence is kind of the Swiss army knife of natural skills. Some animals use it for hunting, while others use it to hide. Others light up to find mates and reproduce. Glowing fungi could be doing any of these things. Some glowing species are edible, and it’s possible that they’re using their light to attract nocturnal insects who will eat them and scatter their spores. But they might also be using their light for protection, by luring in predators of mushroom-eating insects or by advertising their toxicity. It’s also possible that glowing is simply a byproduct of their natural chemical processes. We really don’t know. The mushrooms remain a mystery.

[h/t Sploid]