If you search the right terms on the internet you can find a collection of videos and gifs that depict people stumbling across giant piles of fur in various locations. In the gif below you’ll see a man finding what appears to be a pile of fur that’s… writhing on a park slide. It’s only when he gives it a poke that you suddenly realise exactly what it is.
It’s a giant pile of terrifying harvestmen, otherwise known as daddy long legs or “lame spiders that other spiders don’t invite to parties”. Although, if you’re curious, harvestmen aren’t spiders but they are arachnids making them like scorpions, ticks and mites in that they belong to the same family as spiders but also kind of do their own thing.
Watching that giant pile of fuzz disperse is terrifying to anyone with arachnophobia and it’s easy to see why! No one wants to be anywhere near that.
The video below shows the harvestmen hibernating in a cave, which is a more usual place for them to hang out.
The reason for their clustering is simply about “safety in numbers”. In the video above you can see the cluster vibrating as the man approaches it, a tactic which freaks most predators out and helps keep them safe.
So there we have it. If you’re ever on a caving trip abroad and stumble upon a giant pile of pubic hair then whatever you do, don’t poke it. Well… you probably weren’t at risk of that anyway.