Unbelievable Structures Built By Insects

Let's explore amazing ant buildings and other unbelievable examples of insect engineering and animal architecture!

May 31, 2023・

20 min read

Ants truly sum up the phrase “small, but mighty!”. They’re tiny, six-legged insects, most species of which are smaller than an inch long! But a single ant can lift up to 20 times its own body weight! That’s the equivalent of an average human lifting 4000 pounds, which’d be like you deadlifting an SUV!

But unlike most of us, ants put this incredible strength to work by constructing bridges, towers, rafts, but not from materials, from their own bodies! Let's go for a deep dive into the bug world and find out exactly what those crafty ants and many other critters like them are up too!

Army Ants

In the tropical rainforests of South America and Africa, you might think the fiercest creatures around are the big cats or the giant pythons! But underneath the leaf litter on the forest floor, there is one insect that truly terrorizes lizards, birds, and even snakes! These six-legged soldiers are known as Army Ants.

There are over 200 species of army ants, but most can be identified by their dark-brown-to-black bodies, with orange-colored abdomens. So, if you ever see an ant that looks like its booty has been dipped in fake tan, then you know you’re dealing with an army ant!

They got that name because the behavior of a colony, like a group of soldiers on a mission, is incredibly aggressive and well-organized. They all work together to raid for food in cycles, which have a nomadic and stationary phase.

The nomadic phase is when these ants are on the move, traveling over 1100 feet at a time! Considering an average ant is 750 times smaller than a human being, to them covering a distance of over 1000 feet would be like you running a marathon!

But there’s an important reason why these ants cover such long distances. After all, they say that an army marches on its stomach, and true to their name, army ants are constantly on the search for food. In fact, they’re known for their aggressive foraging behavior, patrolling the forest and raiding resources wherever they can.

They’re so forceful, other bugs live in fear of being swarmed by this insect militia! Such as the poor slug in the image below who, even though it thought it was safe crawling up a tree, became the colony’s afternoon snack.

And even insects that build their nests above ground aren’t safe from an army ant raid. For example, wasps may think that their nest is protected underneath a house eave, but army ants can deploy unbelievable logistical maneuvers such as a hanging bridge!

That looks like a lot of work, but you might be wondering why they didn’t just climb up the side of the house to reach the nest. While Army Ants can climb up things vertically, they have a hard time walking on sheer inverted surfaces and can’t carry any significant loads across them.

So how exactly did they make this bridge? To understand this, we need to learn how army ants assemble themselves into such organized bug bridges. Besides, army ants are practically blind and are only equipped with brains that have a volume of 1 microliter. That’s literally a million times smaller than a human brain!

However, this teeny-weenie brain follows one simple instinctual mechanism: when an army ant approaches a gap in the path ahead, it naturally slows down. That doesn’t seem like a big deal, but the rest of the colony following behind is unaware of this gap and so continues marching forwards at their current pace.

As a result, they end up walking over this first ant, which instinctively freezes in response. The other ants then slow down at the gap and freeze as they too are overrun by the colony. In this way, the ants start to build an interlinked bridge of their own bodies, long enough to span the gap in their path!

However, being blind, individual ants have no idea how many members of their colony are holding fast over the gap. And this is where the next phase of their one rule kicks in. They can detect when the rest of the colony is stampeding over their backs, in which case they hold steady.

However, when they no longer detect many ants crossing, perhaps because there are many others building the bridge themselves, they unfreeze and re-join the march! Just like a stop, start switch in their brains!

This way, ants are able to link together to form utterly amazing structures that can cross over super steep inclines, or even planes set at a 90° angle! Look at them in the clip below, completely unphased by the vertical drop below them! That’s ant power.

Going back to that bendy bridge, it seems that the ants started from the edge of the roof and initially built their bridge in one straight line across to the nest. But as more ants joined the raid, the weight gradually dragged the bridge down. More ants froze in place along the drooping structure, which allowed the other ants to cross over, raid the nest, and carry back their loot!

But bridges aren’t the only superior structure that army ants can form. Unlike those unlucky wasps, army ants don’t have a permanent nest. Rather, when they go into their stationary phase, they can also construct a nest out of their own bodies known as a “bivouac”!

These are large conical structures that can stretch over 3 feet across and are constructed of between 150,000 to 700,000 worker ants linking legs and bodies in a huge network that’d blow the mind of the most experienced human architect!

The human equivalent of a bivouac would be something like trying to live in a house constructed from a bunch of people doing yoga poses! Inside the bivouac, thousands of larvae are located near the center with the queen ant, and workers are responsible for feeding them.

Every 20 days or so, the army ants dissemble the bivouac and march to a new location. But don’t worry about accidentally stumbling into one of these giant ant nests, as they typically hang high up in trees, rotten logs, or inside sheltered sand banks.

Fire Ants

Rainy days can really get you down. You’re either stuck inside all day or left huddled under an umbrella. But while rainy days can be a mild inconvenience to us, on the scale of an ant, a few drops of rain can signal the start of the ant-pocalypse! Without adequate protection, a heavy rain shower can result in an entire colony being washed away!

The places in the world that receive the most rain are the rainforests, as they typically get between 79 to 384 inches of rain per year! By comparison, the US only receives 30 inches of rain per year! So, for ants inhabiting the rainforests of South America, they’re in constant danger of being swept away.

Except, the resident Fire Ant species have figured out an ingenious way to counteract the heavy rainfall of the jungle. If their underground tunnels are flooded, fire ants can link together to create floating rafts that can be held together for weeks!

How long do you think you could float along a river? Most of us would end up sunburnt after falling asleep on an inflatable for 20 minutes; nevermind surviving for weeks on a floating raft! But even if fire ants are better castaways than Tom Hanks, the colony must eventually find dry land if they are to rebuild their nest.

But how do these fire ants create such durable rafts out of their own bodies? Well, the ants themselves are, in fact, waterproof! An individual ant’s hard outer skin, known as the cuticle, is naturally hydrophobic and repels water! That’s because the cuticle’s rough surface allows an ant to trap air against its body, in what’s known as a “plastron layer”.

This ability to create an air shield protects the ants even when they’re pushed underwater, as you can see from the clip below of a researcher trying and failing to submerge a bundle of fire ants. The more ants there are, the more this waterproof ability is enhanced, turning the colony from a life raft into its own cruise ship!

The raft building instinct of fire ants is so strong that as soon as they come into contact with water, they assemble! The ants use their six legs and mandible jaws to hook onto one another, while they also secrete an oily fluid from adhesive pads on their legs.

This fluid allows them to stick to smooth surfaces and basically glues them to one another. The final raft typically forms a pancake shape, but these fire ants can get a little more creative and even form path like structures over any liquid in their way!

However, these water-resistant fire ants do have one surprising weakness: soap! Even a single drop of soap can disrupt the surface tension of the water and destroy the raft, resulting in hundreds of drowned ants.

A useful thing to know, as these fire ants live up to their name as they attack by latching themselves onto a target with their mandibles before delivering a burning sting to the flesh! Fortunately, the ache of the fire ant sting is only short-lived, fading after a few minutes, but it is soon replaced by an intense itching, followed by a rash of pus-filled blisters.

And don’t think you’ll escape the threat of fire ants just by avoiding the jungles of South America, as one species, Solenopsis Invicta, also known as the Red Imported Fire Ant, has already colonized at least 13 states in the US! But not to worry, if you see a raft of these fire ants floating down the street after a rainstorm, then you know the best weapon to brandish in your defense is a bottle of dish soap!

Weaver Ants

A lot of people these days opt for a more natural theme in their décor; whether it’s buying a bunch of house plants, or adding a rope swing to your hipster living room. But when it comes to a “natural” aesthetic, nothing beats the designs of Weaver Ants.

Native to Australia and Southeast Asia, these colonies take natural décor to the next level and construct their entire nests out of leaves! Admiring the simplicity of these weaver ant nests really does spark joy.

To construct these lush, leafy nests, first scout ants locate suitable leaves. Then the colony begin constructing the walls of their nest by either cutting a large leaf into smaller, foldable parts, or by bringing together multiple leaves. Smaller nests can be made of just one single leaf, while larger nests can be constructed of nearly 300 leaves!

Worker ants draw the leaves together by working in coordinated chains of 9-12 ants, they fold the leaves to overlap and hold them in place. Just like army ants, weaver ants possess incredible teamwork instincts and can even construct bridges out of themselves, allowing them to traverse both horizontal and vertical gaps!

The ants are able to balance on one another in a tower, while the rest of the colony use them as a ladder to cross the gap. These agile climbing skills definitely come in handy when they construct their nests in the treetops!

The ants also glue their nests closed by pressing their young larvae against the leaves, because the larvae naturally produce silk as part of their cocooning instinct. When pressed, they deposit this silk on the leaves, meaning they double up as tubes of all-natural super glue!

The worker ants then use this silk to stitch the leaves together, creating their incredible green displays. And the weaver ants don’t just stop with one nest! Rather they create dozens of these leaf hollows across the forest to provide shelter for their huge colony! Other nests are even specialized as nurseries for their young, food storage and even waste disposal sites.

Red Wood Ants

We’ve all had annoying roommates, inconsiderate people who leave dirty dishes in the sink or keep taking your favorite spot on the couch. It can be hard to deal with just 2 or 3 other people sharing your space, let alone living with 250,000 roommates! But for red wood ants, this crowded living arrangement is perfectly homey.

These ants can live in huge colonies with between 100,000 to 400,000 worker ants and over 100 queens who’re constantly laying new eggs! And to house all these ants, they need gigantic nests! Unlike other bugs on this list, red wood ants may not be the most creative when it comes to their nest structures. But what they lack in creative design, they make up for in scale.

Though young nests may be no bigger than a dinner plate, a mature nest can be up to 6.5 feet tall! That’s the same height as Michael Jordan! But that’s only the size of the nest on the surface. Just like an iceberg, what’s above ground is often mirrored or even larger underground!

Inside the nest is a huge network of interconnected tunnels and chambers. Most of the chambers host the queens and larvae, while other chambers are used as food storage, waste disposal sites, and even graveyards!

You might think that all these open tunnels and chambers must put the colony at flood risk and one heavy rain shower and this ant hill could turn into an ant-quarium! However, these engineering ants are already 10 steps ahead.

Up on the surface of the nest is a “thatch” roof, consisting of: pine needles, small twigs, moss, heather, dried grass and pieces of lichen. On first inspection, you may think this is just a random pile of forest litter. But each piece of the thatch has been laid in a precise manner so that rainwater trickles away from the nest, keeping it nice and dry.

The thatch also acts as the nest’s heating system; intercepting the sun’s rays at right angles and acting as a solar panel that raises the internal temperature of the nest. Essentially, these ant hills are waterproof and centrally heated; these ants live better than most people!

No wonder red wood ant colonies are so aggressive when defending their territory. They don’t want other ants leeching off their prime real-estate! However, in one rare case, multiple colonies of these wood ants have managed to put aside their differences and form a single super colony!

On the coastland of Japan’s most northern island, Hokkaido, scientists have discovered an estimated 45,000 Japanese red wood ant nests which stretch nearly 12.4 miles along the coastline!

All the nests are linked by trails and tunnels, through which worker ants can travel freely between each nest. In total this super colony is estimated to contain 307 million ants, with 306 million workers and 1.1 million queens!

Scientists are puzzled by this giant colony, as they are unable to explain how these ants coexist in such a giant empire! In fact, the size of this super colony nearly rivals the third largest population in the world, the US, which has a population of over 332 million people.

Nevertheless, this mammoth ant nest has had centuries to grow to this size, as it is thought to be over 1000 years old! So not only does it have a bigger population than the US, it also pre-dates the US constitution by some 750 years! In that time, these 300 million ants have learned to coexist a whole lot better than us humans.

Silkhenge

Troy Alexander, from Tambopata Research Center, was on a rainforest expedition through the Southern Peruvian Amazon in 2013. When he spotted something strange among the treeline, Troy got closer and discovered a mysterious cocoon consisting of a central spire, like a circus tent, encircled by a neat picket fence reinforced by horizontal web wires.

The internal tent-like structure was only 0.78 inches across: barely the same size as a cherry. The upright fence-like structure was unlike any other insect cocoon previously discovered!

Completely lost as to what it might be, Troy turned to the internet’s biggest collective of armchair experts: Reddit! He posted several photographs of his discovery to /r/whatsthisbug, a subreddit devoted to identifying insects and their handiwork. His post soon went viral, and the strange cocoon quickly gained the nickname, “Silkhenge.”

It eventually caught the attention of real experts, as entomologists around the world weighed in. Yet still, no one could identify what bug was behind this strange tiny cocoon. Given that it was made of silk, it strongly implied a spider. But the question remained, what kind of crafty spider was behind this adorable web creation?

A few months later, another research team of scientists flew out to Peru and returned to the small island where the mystery cocoon had first been spotted. The scientists staked out the area, and along a 650-foot trail, they located 45 different picket fence cocoons, but still the bugs inside them remained hidden.

So, the scientists did the only thing they could do; they sat in wait and watched the cocoons closely. Finally, after 7 days, the central tents parted, and tiny baby spiderlings emerged! Though the actual species of spider still remains unknown, and researchers still aren’t sure why these cocoon nests are constructed with cute picket fences!

They have theorized that the picket fences act to either protect the eggs concealed in the central tent from other predatory insects, such as ants. Or that the web wires contain chemical attractants to lure and trap mites and flies to provide the newly hatched spiders with their first meal. Currently, neither theory has been proven.

Yellowjacket Nests

Can you imagine kicking back in your comfy old armchair then suddenly hearing a strange buzzing noise, feeling a crinkly cardboard texture brushing against your ankles and finding a whole wasps’ nest fused to the chair?

The chair in the footage below is taken over by no ordinary wasp nest, this is a yellowjacket wasp nest; a species of wasp that can be incredibly territorial. And unlike bees, whose serrated stingers get stuck in fibrous human flesh, wasps have smooth stingers, so they can sting you multiple times over!

Wasps prefer a sheltered spot to build their nests, as they are constructed from chewed wood pulp and saliva, creating a paper-like material. As a result, these nests are incredibly vulnerable to water!

Typically, wasp nests are found in wall cavities, roof spaces, under house eaves, or in sheds and garages. But other wasps have constructed nests in some unbelievable places, such as encasing entire bird houses, wrapping the nests around wind chimes, and even bedding into a bed!

Meanwhile, a larger species of wasp, the European hornet, twice the size of a yellow jacket, can build even bigger nests! Such as this passenger-sized nest (in the clip below) in the front seat of a car!

Exterminators will normally use a smoker to calm the hornets because smoke disrupts the chemical signals that hornets, wasps and bees use to communicate to the rest of their colony. Unable to communicate, they can’t organize an attack, allowing our exterminator here to leisurely remove the nest from the car.

That’s a neat trick, but it doesn't work sometimes. The watch this next clip of hornet nest removal. This nest covered the entire floor of an abandoned shed in Patterson, Louisiana, and was simply too large for any targeted smoke to have an effect. So, the exterminator made the brave decision to remove it all, by hand, over the grueling course of 45 minutes.

This may have been a bad day for this colony of hornets, but despite the loss, wasps are actually on the winning side of this war. On average, wasps’ nests can reach the size of a basketball, with 3000 to 5000 of the flying devils inside. However, with climate change heating up the planet, warm-weather-loving wasps have started to build super-sized nests!

In Alabama, there have been over 90 reports of mega yellowjacket nests found around the summertime that can range from a few feet in diameter, up to the size of a Volkswagen Beetle car! And these mammoth nests can contain upwards of 15,000 wasps, that’s a whole buzzing army!

Termite Mounds

Humans have built some impressive structures over the years, like the Empire State Building, the Burj Khalifa, the Shard, and Shanghai Tower! These skyscrapers define the skylines of some of the biggest cities in the world.

But it turns out if one bug was scaled up to be the same size as a human, then their towers would dwarf even the tallest man-made building! Though instead of steel and concrete, these colossal towers would be giant piles of dirt, and host a whole colony of termites!

Termites are found on all continents of the world, except Antarctica. Despite how widespread they are, they’re very difficult to spot, as these bugs are tiny! Worker termites measure between 3/16 to 9/16 of an inch in length. So, on average, a termite could fit snugly into your fingernail.

However, termites don’t let their tiny size hold them back; suitably named Cathedral Termites can build towers as high as 26 feet off the ground! They create these colossal mounds by rolling up balls of dirt and laying them atop each other like bricks, using their saliva as cement.

Building such a hulk-sized mound is incredibly impressive for a creature that isn’t even an inch long. By comparison, the average height of a man in the US is 5 foot 9 inches. While the tallest building we’ve ever constructed, the Burj Khalifa tower in Dubai, stands a staggering 2,722 feet above the ground.

But if termites were scaled up to be the same size as humans, then the towers they could build would also be scaled up proportionally and end up the height of four Burj Khalifa’s stacked on top of one another! That’s 10,888 feet tall, that’s 60% up the first layer of the atmosphere!

In addition, termites don’t just build proportionally bigger towers than us, they also beat humans to the invention of air-conditioning! Inside their dirt towers is a sophisticated inner network of tunnels, with a large central ventilation shaft and thinner chimneys branching off it at the sides.

During the day, air in the ventilation shaft remains relatively cool, while air in the narrower chimneys on the outer edges heats up quickly. Cold air is denser, so it sinks down the shaft, while hot air rises up and through the chimneys. This ensures the termites have continuous cool air flow through their mound, preventing them from becoming baked into termite fries!

And at night, the air flow amazingly reverses, as the air in the narrower chimneys cools down quicker than in the central shaft. And so cold air sinks down the chimneys and warm air rises up the central shaft. This ensures the termites have a constant supply of fresh air overnight!

It's solely the worker termites that are responsible for tunneling and building these massive mounds. They also collect food for the colony and take care of the Queen termite, who sounds like she’s living the high life. But be warned, these bug queens are the exact opposite of a dainty woman in a crown, rather a horrifying swollen egg-laying nightmare!

No wonder termites build their towers so tall; they need all that space to hide their super huge, hideous queens! I hope you were amazed at these unbelievable structures built by insects. Thanks for reading!