These are horsetails. They are hundred-and-fifty-million-year-old plants and the last of their kind. Instead of seeds, they give off spores. And instead of flying or swimming, these spores use humidity to walk, or even hop, on four little legs.

Okay, this is incredible. Horsetails, or equisetum, are one of those “living fossil” plants that have managed to hang on after most of the rest of their family has died off. They look like someone cut a single branch off a Christmas tree and stuck it in the ground. When they reproduce, they send out spores, which look like little round seeds with four “arms” curved around their body. As it gets humid, here’s what happens.

Yep. The offspring of something named after horses trots on four legs. It’s not as graceful as a horse, but it’s been around for 150 million years, so clearly it gets the job done.

Image: Kristian Peters