The diving bell and the water spider: How spiders breathe under water

Water spiders spend their entire lives under water, only venturing to the surface to replenish their diving bell air supply. Yet no one knew how long the spiders could remain submerged until Roger Seymour and Stefan Hetz measured the bubble's oxygen level. They found that the diving bell behaves like a gill sucking oxygen from the water and the spiders only need to dash to the surface once a day to supplement their air supply.