There’s No Place Like Home: 4 of Nature’s Savviest Homeowners

These four creatures build, or steal, homes so wild you might want to move in yourself. A cozy silken tent, a rugged mobile home by the shore, and a custom-built loft that serves up an all-you-can-eat buffet. First, caddisflies build underwater stone hideouts using organic tape. To us, it's a tranquil mountain stream. But if you're a bug living on those algae-covered rocks in the water, it's a constant underwater hurricane. Powerful currents, debris swirling all around you. How do you survive? Well, you build a shelter. All you need are some raw materials and a little tape. That's right, tape. This is the larva of the caddisfly. This insect has evolved a tool that's eluded us humans so far. Tape that stays sticky underwater. As winged adults, caddisflies are a favorite food for trout. Artificial lures mimic them in painstaking detail. But they spend most of their lives as larvae in shallow, turbulent water, which is rich in the oxygen they need. And though its head and legs are covered in a thick layer of insect armor, or chitin, its soft, white lower body is more exposed to the elements. And especially to any passing predators. So the caddisfly has figured out how to build a case for ballast, protection, and camouflage. It does this by binding together pebbles with a special silk that looks, and acts, a lot like double-sided waterproof tape. Every case starts with one pebble. It's like the cornerstone of a building. The caddisfly adds more pebbles, one by one, like a bricklayer putting up a wall, using its tape as the mortar. When he brushes the surface with his mouth, that's his tape dispenser working. It's in a gland under his chin. He's sealing the pebble down. These flies are very particular about their building stones. Only the right shape and size will do. If it doesn't fit, it's out. When he finds a match, he fits it into place. Once he tapes down the basic shape of the case, he seals it up from the inside in a series of barrel-roll maneuvers. The problem with our tape is that when it's wet, it loses its stick. But caddisfly tape is selective. It sticks to pebbles, but not to water. What's more, the ribbon itself is like a rubber band. It can stretch to twice its size and return to the same shape. But it snaps back slowly. It's a rubber band that moves like molasses. So the case is resilient. No quick movements. That's a lot safer for the vulnerable larva living inside. Bioengineers have started to figure out how we could make our own caddisfly silk, maybe as a kind of internal surgeon's tape, to replace the metal and string that we use to patch people up now. The magical underwater tape of the caddisfly. Another example of how evolution finds radical solutions to everyday problems. Like how to survive in a hurricane. These webspinners put your knitting projects to shame. They craft their sprawling homes with their feet. OK, under a log, you uncover a wispy white web. You're thinking, spider. Not so fast. This maze of woven silk has nothing to do with arachnids. It's actually created by a kind of insect called a webspinner. They're related to stick insects and praying mantises. Never heard of them? Not surprised. They give spiders a run for their money. Their handiwork is a tent, umbrella, and invisibility cloak all in one. But while spiders produce silk from their back ends, a webspinner's silk comes from her feet. Yep, her front feet. She intertwines the strands, waving back and forth, back and forth. She has tiny hair-like ejectors on the bottom of each foot. Which shoot out the silk. It's the thinnest silk of any animal. The work is painstaking. But the result is pretty cozy. Kind of like a quilted roof. Their home, also known as a gallery, is their only defense, hiding their soft bodies from predators. There's also plenty of moss and lichen to eat inside. So why leave? And if they need to do some housekeeping, it's easy to take out the trash. They just stick it to the roof. And forget about it. The silk also keeps out something they really like to avoid – rain. Webspinners can easily drown if a downpour floods their gallery. Luckily, they've got exceptional weatherproofing. Water just beads up on the silk's surface, like on a rose petal. And that water actually changes the silk, making the surface more slippery by transforming the proteins. So it becomes extra waterproof. But having silk-slinging front feet has a downside. Say an unwanted visitor comes along. If they want to get away, webspinners have to tiptoe to avoid triggering their silk ejectors. Not exactly the fastest runner. So to escape, webspinners dart backwards to avoid getting tangled up. They're much faster in reverse. Small price to pay for the ability to weave an entire hidden world. One that will keep the webspinners – and their young – safe for generations to come. Hermit crabs are always looking to upgrade their homes. And if they find one they really like, they won't hesitate to give their neighbor the boot. Hermit crabs are obsessed with snail shells. And these crafty little crabs are more than happy to let the snails do all the work to make their future homes. In these northern California tide pools, turban snails invest years – sometimes decades – growing their shells. They pull calcium carbonate right out of the water to do it. They spend their days eating the algae that coats pretty much everything in these rocky, shallow pools. The rugged shells protect the snail's squishy bodies from the relentless surf. They're way stronger than your average garden snail shell. Those sturdy curves catch the attention of these grainy-hand hermit crabs. But hermit crabs won't kill the snails to get them. They wait for a snail to die, and then rush in. This new home comes with a free meal. Escargot, anyone? It's a competitive market. And they're constantly looking to upgrade. Maybe they've outgrown their current place. A shell that's too small hampers growth. And a damaged shell like this one just isn't safe. While the front of their body is covered in stiff armor, their elongated back half is soft. It curves to match the shell's spiral shape. At the very end of its body, deep inside the shell, modified legs called uropods grab on, like the arms of an anchor. Before they make any big moves, they usually inspect their new potential digs. If they like what they see, they make sure the coast is clear, hold on to both shells, and… Much better. Now to get this place cleaned up. But the crabs never get too attached. They might occupy this shell for just a few hours if they find something better. Sometimes hermit crabs will squabble over a particularly desirable abode. Or bully the current occupant into abandoning its shell by banging against it. But the tenant hiding inside won't give up its most prized possession easily. If there's one thing they can count on, though, there will always be another shell. And another. An orb-weaver spider builds a web that's more than a home. It's an extension of the spider's senses. Some of nature's most mesmerizing works of art might just be hanging in your backyard. The artist is an orb-weaver spider. Though it has eight eyes, it's practically blind. And its sublime compositions aren't just deadly traps. They're an extension of the spider's senses. Spider creations come in many forms. Tangles. Funnels. Sheets. Even mixed media. Intricate spirals are an orb-weaver's signature design. There are thousands of orb-weaver species, each with its own style. Like this trash-line orb-weaver. It hides out in its string of past victims. Spiders are born web-spinners. See these spiderlings? Testing out their skills. To weave these webs, the spider secretes silk through organs called spinnerets. Spider silk is made mostly of proteins. The spider uses different types of silk for different purposes. To start, the orb-weaver lays down a scaffolding using a smooth, structural silk. Then the spider switches to a sticky silk for its main motif. Circle after circle of tenacious thread. Its eyes only see light, dark, and a little movement. So the orb-weaver builds by feel. The spider constructs its ephemeral home in just a few hours or less. The delicate-looking web is actually five times stronger than steel. If it were scaled up to human size, you couldn't just sweep it away. If the spider's hungry, it can tighten the strands of its web, making it easier to sense prey. When a fly crashes into the sticky web, its impact reverberates. Since the spider can't see well, it feels nearby spokes to zero in on its meal. It uses sharp fangs to inject a paralyzing venom. Then the orb-weaver basically shrink-wraps its prey using a wide sheet of silk. When it feeds, it repeatedly bites the wrapped-up prey, liquefying it so it can suck up all the juices. Once a meal is all wrapped up, the spider can store it in its pantry for later. It has no problem finding it again. Only a handful of invertebrates can remember where things are like this. So how does an orb-weaver do all these things with a brain the size of a poppy seed? Some scientists think a spider's mind radiates out through the strands of its web, beyond the limits of its body. It seems this exquisite creation is not just a home, a sophisticated net, or a place to keep food. It's a map of the spider's memories.