Lots of baby spiders never crawl very far from where they hatch. Plenty of others fly across countries.
When a spiderling wants to find new territory, it climbs up high - to the tip of a leaf, the top of a fence - sticks its bottom in the air, and shoots out a tuft of silk strands. The silk doesn’t catch the wind like a sail. Instead, the strands catch the planet’s natural electric field - Earth has a small positive charge in the atmosphere, and the negatively charged silk threads literally repel away from the ground and lift the spider into the sky.
Once airborne, spiders can drift for hundreds of miles. Researchers have caught ballooning spiders 2.5 miles up in the air, and on ships far out at sea. Some species use this to colonize entire countries, sailing across oceans on a few strands of silk and a tiny static charge.
