If you’re an air-breathing animal, how do you stay under water for a long time? Aquatic mammals, like whales and seals, must come to the surface and take big gulps of air. Humans can do this, too, but nowhere near as well. We get some help from scuba gear, which includes air tanks and special breathing equipment (the letters of "scuba" stand for Self-contained Underwater Breathing Apparatus).
Before scuba diving came on the scene fifty years ago, divers wore a big helmet. All the air was pumped along a tube that led from the helmet to a boat. You can imagine how dangerous it was to have a long tube that could get snagged or break. But the diving helmet was just one step away from the diving bell.
Diving bells have been around for a very long time. The idea was to lower a bell-shaped container into the water with the opening at the bottom. The air was trapped inside, which means that someone could stay inside the bell and breathe as it was lowered into the water. You can see how this happens in the kitchen sink. Take a glass, turn it upside down, and push it into a sink full of water. The glass does not fill with water because the air inside has nowhere else to go.
But before man came up with scuba gear or the diving bell, one spider was doing very well underwater. This is the water spider of Europe. It weaves a basket-like web among some plants growing in the water, and then it comes to the surface. As it dives back down again, it carries air that has been trapped against its body. The spider pushes this off under the web, and it collects to form something like a diving bell. It keeps doing this until the bubble is big enough for itself, and a tasty snack or two. The water spider is a quick swimmer, a good hunter, and has a potent bite. It can do everything in water, except breathe and eat its food.
How did the water spider become so successful? If this happened by chance, we might think that a few other species of spider would take advantage of the watery world. But the water spider is the only one, and it does it so well. The water spider is so special that it shows all the signs of being designed by our Creator God just for this purpose.