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00:00Humans aren't the only animals built to build.
00:04These six animal architects have evolved to engineer amazing structures.
00:09Some using found materials, some using their bodies,
00:12and some creating their construction materials inside their bodies.
00:17Though the process differs greatly across species,
00:20comparing the way nature executes her builds
00:23will reveal what these animals can achieve
00:25is equally as impressive to any man-made marvel.
00:29These are the builders.
00:56The beaver is perhaps the animal kingdom's most iconic builder,
01:00famous for one thing, this incredible structure, the beaver dam.
01:06If there is running water, a beaver will dam it.
01:10It's not that they're consciously deciding,
01:13this is where I'm going to build my dam.
01:16There's an instinct, a drive to do this.
01:19They are the ultimate contractor, you know, except they work hard.
01:23They create these amazing structures and lodges,
01:27but really what they've done is created a world that works for them.
01:31Beaver dams are impressive structures, massive and built to last.
01:35There are dams still standing that were first mapped 150 years ago.
01:43If you look at a beaver dam and you see a beaver,
01:46they're constantly working on their dam.
01:49They're trying to make it stronger.
01:51They might even try to make it bigger.
01:54Some of these beaver dams get pretty large
01:56and personally, you know, having canoed through backcountry,
01:59I've seen beaver dams more than 250 metres in length.
02:03So it's pretty amazing when you come across a dam
02:06and it's actually bisecting almost an entire water body.
02:10The longest beaver dam ever found stretches 850 metres,
02:14twice the length of the Hoover Dam.
02:16So long, in fact, it is visible from space.
02:20They are quite complex, having multiple exits and entrances.
02:24These beavers create these dams that are not easy to get into for their protection.
02:29So no other animal can come in and they are protected.
02:32The other thing that's interesting is what you see of a beaver hut is only a small amount of the
02:37structure.
02:38There's a large amount of structure below the water level that extends out from the hut.
02:42So there's all of these interlocking sticks that extend out from those entrances and exits and hide where they are.
02:50The building skills of these ingenious wetland architects are their primary defence.
02:58They're not even particularly fast.
03:01They don't have claws or teeth that can harm a predator.
03:04Their defence is their environment.
03:06I think that's really why they live the way that they do.
03:09As aquatic mammals, the ability to escape over water is what they rely on.
03:15So creating these flooded landscapes means that they're creating an environment in which they are safe, essentially.
03:20But beavers also built dams as a way of manipulating the environment to their advantage to gain greater access to
03:27food.
03:27In doing so, they have a significant impact on the environment.
03:32There's very few animals on planet Earth that augments entire ecosystems as much as the beaver.
03:38It creates huge amounts of bodies of water.
03:42When you look at images of the Laurentian Shield in Canada, for example, which is primarily exposed granite,
03:49with swampy water bodies in between, if it wasn't for the beaver, those swampy water bodies wouldn't be there.
03:56It's hard to list all of the things that benefit from beavers because there's so many individual things.
04:01But on a broad scale, marsh birds, grails and herons, shorebirds like sandpipers and plovers.
04:10Fish use these marshlands and wetlands as breeding habitats.
04:14So do aquatic reptiles like turtles.
04:17So do amphibian species.
04:19The flooded landscapes that beavers create are home to a whole suite of living things.
04:25And also plant communities as well.
04:27Beavers create the conditions that certain plant communities and species need and require to thrive.
04:34The number of beavers in North America is rather astounding, numbering into the millions.
04:39So we are not talking about one or two ponds or water bodies.
04:44We are talking hundreds of thousands of water bodies that these beavers are creating.
04:50And that is a really important part of the North American ecosystem.
04:54These ecological engineers are amphibious rodents.
04:58The second largest rodent in the world.
05:01They can get as big as 80 centimeters and weigh close to 16 kilos.
05:06And even though their work creates a biologically diverse feeding ground,
05:10the beaver's primary food source is plants.
05:15They've engineered the habitat and it acts as a place where water can collect,
05:20which then means there's vegetation growing.
05:22They do this manipulation to actually increase the probability that plants will grow where they are,
05:28which means that's what they can eat.
05:30Another of the beaver's food sources is also the building material, wood.
05:35When you come across a beaver dam, you really understand how complex this mound is.
05:42It is a lot of work to put these branches together from specific wood and then look at how the
05:49mud's been packed into it.
05:51And then you look at the animal that did it and you wonder how was that little thing been able
05:58to build this huge structure that has caused the dam and created a wetland in its space.
06:03When starting to build a dam or lodge, beavers take down trees near the stream they intend to block using
06:09their teeth, gnawing around it until gravity takes over.
06:13These trunks are pretty thick and the way they go after the wood, the pattern that they do is deliberate,
06:20but it takes a toll on grinding down those teeth.
06:24They also have to carry it back and a lot of times they use their mouth and those teeth play
06:28a big role in gripping that trunk and bringing it over.
06:32The beaver is well known for its prominent long front teeth.
06:35Those teeth are essential machinery needed to build.
06:39They're not just simply tough, they are in fact metallic.
06:44The enamel and the beaver's teeth contain iron, making them a kind of biological chisel.
06:52You're taking down trees that are pretty tall.
06:55Some of the wood is pretty hard.
06:57The teeth have to be extremely strong.
06:59That means they need to be long, they need to probably be thick and they need to be sturdy.
07:03Those metallic teeth are set in an incredibly strong lower jaw that gives the beaver the power to continuously gnaw
07:10through a tree trunk and drag it where it needs to go.
07:13Your teeth continually grow throughout their life and they're actually quite substantial, including the part that extends into the skull.
07:21They're five or six inches long.
07:23So as they're worn down by the gnawing and the cutting down of trees, those two main chewing teeth at
07:29the front continuously grows to replace the material that's lost.
07:33The beaver's teeth grow at an impressive rate of half a centimeter a month.
07:37Keeping them sharp is essential to their survival.
07:43The sound of running water is what triggers the dam building process.
07:47The fell trees form the base.
07:50Branches, twigs and mud form the rest of the structure.
07:54It's really quite impressive because at the outset it looks rather haphazard.
07:59There's actually an underlying structure to it.
08:01So when you look at a branch that comes off a tree after the beaver chews and cuts it off,
08:06it starts wide in the leafy area and then narrows down to a single stalk where it would attach to
08:13the tree.
08:13Well, the beavers position each one of those branches so that heavy stalk section is downstream and the leafy section
08:21is up on the bulk of the dam.
08:23And basically as they build up the leafy sections and add mud and build up leafy sections and add mud,
08:29each of those stalks and branches acts as a buttress to support the dam so that the dam doesn't get
08:35pushed downstream.
08:37Beavers will create canals and trails to facilitate moving the material they need for the lodges and dams, extending the
08:44built environment into a new ecosystem.
08:47Beavers are what we call keystone species.
08:49And if you remove them and you remove the work that they do in flooding landscapes and directing water and
08:55creating wetlands, everything else that lives in those wetlands kind of collapses around them as well.
08:59They are exceptional little engineers. They do a really good job at making a dam work and be functional.
09:05But it's pretty amazing that as engineers, there's a huge amount of science that goes into building just an earthen
09:12dam, let alone a concrete reinforced dam or something like the Hoover Dam.
09:16Those are major engineering undertings. But even Beavers are able to do this without a lot of input and do
09:23it relatively successfully.
09:24These dams last decades or even longer in the same position maintained by many generations of Beavers.
09:31So it's really quite impressive.
09:33Building a structure is one thing. Creating complex systems within it is a completely different task.
09:39But that's exactly what these, one of the smaller, simpler creatures do.
09:44Mountain building termites are superior architects who build these impressive mound structures, completely ventilated with tunnels and chambers.
09:51It's really just fascinating to me. Most animals, they'll dig a hole and they'll make a nest or they'll take
09:57a hollow log, create a nest there.
10:00But, you know, that's kind of the beginning and the end of most construction in the animal kingdom.
10:03And then you do have this relatively small group of organisms that go all in and they build these structures,
10:10almost palaces in some cases.
10:12Some of these termites build mounds that are 30 feet high and 30 feet wide.
10:19In Brazil, there was actually found a termite megacity.
10:22You can see that there's mounds and networks that termites have built for hundreds and hundreds of years.
10:28The termite megacity in Brazil covers an area of 230,000 square kilometers, roughly the size of Britain.
10:37There's upwards of 200 million of them. These are incredible engineering feats on a human scale.
10:45We're not talking about a big animal. We're talking about something that's certainly smaller than my baby fingernail.
10:51How does the tiniest of insects move so much dirt? By some estimates, enough to build 4,000 of the
10:58great pyramids of Giza.
11:00Your mind just gets blown at that intricacy. For a colony, the power is in numbers. So, obviously, there was
11:08a time where this colony was large.
11:11There wasn't a lot of disturbance and it was allowed to build that big of a colony.
11:16Brazil is perhaps the largest termite development, but mounds just as high and just as ancient exist in Africa, Asia
11:24and Australia.
11:26There are ones in northeast Australia that are oriented north-south and they're very thin this way and very broad
11:34the other way.
11:35And they're called magnetic mounds and it's basically aligned with the magnetic field.
11:40Then you have ones in a savanna habitat where they've got a long, thin one. And when it's in a
11:46forest, it's a short, squat one.
11:49Termites adapt to their specific environment, building various thick or thin-walled mounds depending on their surroundings.
11:56And each one is built bit by bit.
11:59It's hard to figure out how these animals get that blueprint or instructions on how to create these mounds.
12:06And it just happens through their efforts together that they create these structures that are beneficial to their entire group.
12:13Evolutionary engineering has turned these insects into mighty builders. But just how do they do it?
12:19When termites are building mounds, it first starts with mixing soil, its saliva and water with additional pheromones into a
12:26blob or a pellet that they drop.
12:28Other termites are then attracted to this pheromone concentrations and further builds onto it until it rises to a pillar
12:34or a wall.
12:36Once there's enough of that wall concentrated in that area, they then move to a different spot until all of
12:42these walls connect together, building that mound.
12:44It's the collective effort of these termites and the pheromones circulating in the air that allows them to build these
12:51mounds.
12:51Even more surprising, mound-building termites don't live in these elaborate structures.
12:57There's actually an underground system underneath that mound where they would nest and have their brood and their queen and
13:03everything else involved in a termite colony.
13:05So what exactly is their purpose?
13:08That is your domicile, but it is also built in a way that will give you protection.
13:13There are animals that, you know, aardvarks and anteaters and stuff that will attack these social insects.
13:19And of course, termite mounds, you almost need a jackhammer to open up some of them. They're so hard on
13:24the outside.
13:25But in an ingenious twist, mound termites have evolved to become experts in heating and cooling.
13:32Those structures are keeping the temperatures in the mound relatively uniform over the course of the day, making sure that
13:40there's good air exchanges so that we're getting rid of the CO2 and bringing in fresh oxygen, making sure that
13:46the environment's not going stagnant.
13:48It's not just, you know, regulating temperature, they're regulating the moisture level.
13:52If there's too much moisture in a mound, they're going to open up some air to get through to dry
13:56it out, because if mold gets into that mound, it's not a good thing for the colony.
14:00Mound-building termites work continuously, plugging holes and building new tunnels to keep the temperature regulated inside their nests.
14:08Termites, it would seem, are the natural world's thermal engineers.
14:12Passive heating and cooling is very difficult to achieve and do it well. So the fact that the termites have
14:18been able to build these structures that inherently control that temperature and humidity is pretty amazing.
14:25Their evolutionary biology has made sure that when they construct these things, they're actually very efficient and do what's needed.
14:32In human engineering, we typically rely on mechanical ventilation systems to keep our buildings heated and cooled.
14:38We could learn a lot from the passive systems created by termites.
14:43It's really hard for us as engineers, without designing really complex systems that have actuated dampers and fans that turn
14:51on and off, et cetera, to control the temperature in that room, let alone the temperature in every room in
14:56the house.
14:57And the fact that termites are able to build these passive systems that inherently solve all of those air conditioning
15:06and heating issues for the colony is really quite amazing.
15:09And it's, again, one of those evolutionary advantages that they've learned to build these structures that essentially make sure they
15:16live in their ideal environment year round.
15:18Creating intricate structures with environmental control is not only the domain of the termite.
15:25Some of the animal kingdom's most skilled builders are also some of the smallest.
15:30The bee, one of nature's most venerated creatures, is also one of its most diligent contractors.
15:37When we think about bees, we always think about the result, what they provide us, the honey.
15:41And we love the honey, and so we love bees.
15:44Gathering honey and beeswax from a hive has been part of human history since the Stone Age, roughly 9,000
15:51years ago.
15:52But bees do far more than make honey and beeswax.
15:56Bees are critical to our survival.
15:59Without bees, we wouldn't have that pollination.
16:01There'd be a lot of problems, not only for flowers, but plants and trees and so forth.
16:07Trees and plants are a big way of getting oxygen other than from the ocean.
16:11Flowering plants have been around for, you know, hundreds of millions of years.
16:14Bees have evolved not too long afterwards to start pollinating them to take advantage of the nectar source that these
16:19flowers provide.
16:21Pollination is taking pollen from one flower to another
16:24to create not just more flowers, but fruits and vegetables.
16:28All sorts of bees pollinate.
16:31Today, there are over 20,000 different species of bees.
16:34A lot of them are solitary, and they just kind of do their own thing.
16:37They'll create nests in the ground, and often they only live one season,
16:41and so they lay their eggs in these straw-like tubes, and they'll plug off a layer for each egg,
16:47pack it in with food, seal it up, lay an egg, fill it with food, seal it up, and go.
16:53But it is honeybees and bumblebees who are some of the most efficient and numerous pollinators in the bee world.
17:00We all think about bees as pollinators.
17:03Well, there are some plants that can only be pollinated by what are called buzz pollinators, like a bumblebee.
17:10Fumblebees are the teddy bears of the sky.
17:13They're fuzzy, they're huge for insects.
17:16The way that they putter along as they're buzzing, it's like they have nowhere to be.
17:20They're all performing really essential tasks, but they just kind of fumble along from flower to flower.
17:25They're really clumsy in the way that they fly almost.
17:29And they can absolutely load themself up with pollen.
17:31You know, you see sometimes these orange saturation of pollen into their honey baskets on their legs.
17:38They're by far the cutest organisms in the world, and I will fight anybody for that.
17:43Honeybees aren't as large as the bumblebee, but they are one of the most amazing builders.
17:48Honeybees themselves don't build a dome structure or a conical structure.
17:53They find a hollow log and they start building the actual combs inside the hive.
18:00And those are relatively amazing systems in that they're composed of a polymer beeswax,
18:07which is relatively strong and flexible.
18:11Honeybees construct these huge structures out of beeswax, which are filled with these amazing hexagonal chambers.
18:17What we don't really spend a lot of time on is how perfect the shape of the honeycomb is inside
18:25the hive.
18:25And I think that's something that's extremely fascinating with these builders,
18:30is the fact that they can just come up with these plans over and over and over again and build
18:34these perfect structures.
18:37When bees first build these cells, they actually come off as circular.
18:41They use their body heat to melt it in a way to allow it to gain that hexagonal shape.
18:48This is the most efficient shape to use.
18:51It's the least amount of wax to build a receptacle that will hold the most amount of honey.
18:56If you were to design an apartment building to get the largest number of units into the smallest area,
19:02that would be the way to do it.
19:04Most people couldn't draw one that exactly.
19:07They're not there with pliers and tape measures and everything else to work it out.
19:12The depth of it is by their own body length.
19:15They want to make sure that they're all the way in, because then they know that if you put a
19:20cap on it,
19:21it'll be big enough for the larvae and the next worker that's coming out.
19:25Each section has a specific compartment or section.
19:29There's the honey area, pollen area, there's the egg cell area, there's the drone area, there's the queen area,
19:36and there's different chambers that they organize this in.
19:40Honey bee hives are incredible weight-bearing structures.
19:44A complete honeycomb can hold 30 times its weight.
19:47There are different types of bees within a hive that have their own specific functions,
19:52and they will stick to that function.
19:54They will not disobey in terms of their role as a job in the hive.
19:58And so, seeing that colony continue to work and function, and seeing how perfect those shapes are
20:04and how integral the structure is just goes to show how everybody working their own job works.
20:11How is it that these tiny creatures can build such a complex structure?
20:17When we look at bees, we don't think of them as builders.
20:21But when you actually look inside, it's not haphazard.
20:24They really are working as a collective group, not only on active engineering and building combs,
20:30but on passive engineering in that the combs are arranged in a way that the hive doesn't suffocate,
20:36it doesn't become overheated.
20:37They're making sure that things are kept clean and not allowing bacteria to get in there,
20:42and the honey is going to spoil.
20:44There's a lot that's going on there, more than just those structures themselves.
20:49Honeybees use their bodies to create their building materials.
20:52When a bee undergoes its metamorphosis from the larvae and turns into an adult bee,
20:57it'll start to have these glands on the side of its abdomen,
21:00which will secrete a colorless, waxy substance.
21:03Bees will pick that off, they'll start chewing that,
21:06they'll mix it in with things like pollen, with a little bit of honey,
21:10and then it becomes that more opaque, kind of translucent wax that we're used to, that beeswax.
21:15The hive is well organized around the role that each bee plays,
21:18and that structure centers around the queen, who is fertilized once
21:22and spends the rest of her life laying eggs.
21:25The TV portrayals of hives being controlled by queens, that's just not the case.
21:30There's a biological need to support that queen,
21:33to make sure she's fed and that she can procreate,
21:35but she's not giving signals to bee number 452
21:40to create a new section of honeycomb in the back of the hive.
21:43It's all inherently ingrained into the collective genetic memory of the hive,
21:50of how it's supposed to perform.
21:52Each of those individual bees are working together to achieve a common goal.
21:57It's absolutely amazing.
21:59Bees have evolved to instinctively know their roles, known as swarm intelligence.
22:05It's not like there are sections of the hive and each one has a manager or a foreman.
22:09It's all kind of an innate understanding.
22:12It is a collective intelligence, but it's also a gene memory aspect.
22:16When you look at colonies, they have a job to do and they're going to do it.
22:19They don't have the intelligence to build a better or worse.
22:23They just do what they're programmed to do.
22:26When the bees come out, they actually work up through the hierarchy.
22:32For the first couple of weeks, they basically stay in the hive and they do different jobs.
22:39They can be cleaner uppers, they get rid of anything that dies.
22:43When the larva is ready to pupate, they have what is called capping,
22:48so they will cap each of the cells.
22:50Eventually, they will end up being the guards at the door.
22:54And then in the last part of their life, they're foragers.
22:57The astonishing strength of the social order has evolved for one simple purpose.
23:02The whole reason they build these structures and they transform nectar into honey
23:06is because they need to survive the harsher winters.
23:08When there are no flowers, when they can't forage to get food,
23:11they need to produce this food to last them through them.
23:13That foraging has given us some of the greatest beauty in the natural world.
23:18Bees have much to teach us about creating sustainable and long-lasting structures.
23:22But what can we learn from nature's most individual builder, the spider?
23:30Newborn spiders.
23:32Just starting to find their way along their mother's web.
23:36Not long after they're hatched, a spider's instincts take over.
23:40When young spiders hatch from their eggs,
23:43they'll actually spin a tiny web that they trail out behind them.
23:48And due to the drag on that thread that they've spun,
23:51the wind will pick them up and carry them to a different spot in the area.
23:57There are roughly 45,000 species of spiders in the world.
24:02They come in all different shapes and sizes,
24:05live in many different habitats,
24:07and they all produce this incredible building material known as silk.
24:11So essential that making it is the first thing a spider ever does.
24:15The species that we do know about now have specific roles in each habitat.
24:21Some are living under tunnels, some are web builders.
24:25They just have so much variety,
24:26and it's interesting to study each one case by case.
24:29Spiders have been making webs for over 250 million years.
24:33They are one of the animal kingdom's top builders,
24:36and their silk is the construction material of choice.
24:40They use it not only to build habitats, but also to trap prey,
24:44to escape predators, to make nests for their young,
24:47and sometimes they even eat it.
24:50It's simply an amazing material,
24:51and essentially it's a polymerized protein,
24:54and it's exceptionally strong.
24:57They create a substance that's exclusively for building.
25:00It's such a light, strong, amazing substance,
25:04and yet it's something that they can't help but make.
25:07A spider's body comes equipped with glands
25:09that secrete the early stages of silk into long ducts
25:13that lead to the spinnerets located on the spider's abdomen.
25:17It's really kind of cool because it doesn't actually form
25:20until just as it's leaving the spider's spinneret organ,
25:24so it's almost instantaneous silk.
25:28It doesn't exist until it decides to produce it.
25:32Each spinneret has a spigot that controls the thickness and speed
25:37at which these nanostrands are cast off.
25:40The faster you're able to do a specific task,
25:44a lot of times the better it can be,
25:46from a spider spinning a web at great speeds
25:50to set up its ability to catch prey.
25:53That's an advantage.
25:54That increases your survivability
25:56to anything that Mother Nature will throw to you.
25:59The spinnerets then wind these nanostrands together
26:02to form a thread of spider silk.
26:05Spiders have an amazing amount of control over this process.
26:09Different glands produce different strands,
26:11which can be wound together to create various types of silk.
26:15Some sticky, some elastic.
26:18Each one has a different purpose for building.
26:20It's really amazing to me that biology can come up
26:24with such creative ways to do things
26:27because when we make polymers and plastics,
26:30we don't go straight from oil to fabric.
26:34There's a whole bunch of stages we have to go through
26:37to get to that point.
26:39But the spider biologically just creates this amazing fiber
26:44that as engineers we have a hard time matching
26:47even in properties, let alone ease of production.
26:50A spider's web can seem like the most delicate structure on Earth,
26:54but in actual fact, it is one of the strongest.
26:57Pound for pound, spider silk is just as strong as steel.
27:02You could make one steel cable about yea thick.
27:04You could make one out of silk that's about the size of my little finger,
27:08if you could do it.
27:10So far, we're a long way away from that.
27:12And what spiders do with that silk is nothing short of astounding.
27:17There's different types of silk that they'll use in individual webs,
27:21and the webs can take a lot of different shapes.
27:23The traditional web that we think of spiders building is the orb web,
27:27the web that has the traditional spider web shape that we see every day.
27:32And that's a really interesting design because it's really meant to capture insects.
27:38Spiders first start building their web by climbing up to a high structure
27:41where they then cast a single thread.
27:44This thread is then blown by the wind and it attaches to a certain point
27:48and anchors it to that area.
27:50Once the spider is sure that it's anchored to that specific point,
27:53it then drags itself down with its body weight and then anchors that point to other areas,
27:59creating more points where it could support itself.
28:02And from the center, it then creates these things called radial spokes
28:05and then begins building that spiral from inside out.
28:09But that web isn't just one type of strand.
28:13The strands that run radially towards the middle and anchor the web are one type of thread.
28:18And then the thread that forms a spiral pattern of this sticky material that traps the fly or the insect.
28:25The net casting spider produces, as you would imagine, a net.
28:29It's almost like a fishing net.
28:31And it's just like you've seen old pictures of people in a boat throwing out a net
28:35and then bringing it back in.
28:37Well, they do the same thing.
28:38We think we're pretty clever, you know, we've worked out how to do this, this and this.
28:42And little organisms with brains the size of a pinhead have evolved to do exactly the same thing.
28:49It's also the speed at which they create things that are so much larger than their bodies.
28:53Everybody knows, you know, you like leave a patio chair somewhere for an afternoon,
28:57you come back the next morning, suddenly there's this insane web structure that's enormous
29:01and it's taken them just a couple of hours to create it.
29:05Some spiders build their webs at night and consume them in the morning
29:09for reasons that are not well understood.
29:12Speculation has it that the spiders are drinking the morning dew
29:15or preventing birds or other larger animals from getting caught.
29:20Not all spiders build webs or use webs.
29:22You have the orb weavers that build these kind of traditional webs.
29:26Then you have the ones that build these funnel webs and then all sorts of other varieties.
29:30Other forms of silk structures include unobstructed cobwebs, mesh webs, sheet webs.
29:37And some are even able to create structures that allowed them to flow underwater.
29:42The diving bell spider is an astonishing builder.
29:45This spider lives completely underwater, taking in oxygen from a sphere-shaped web structure,
29:51its own personal diving bell.
29:53It's interesting because it's really outside of the realm of human experience.
29:57We are not able to do anything remotely close,
30:00so we don't have any frame of reference for comparison in our own lives
30:05because we don't do anything like it.
30:07But that hasn't stopped humans from trying to create spider silk.
30:11Engineers aspire a lot to the properties of spider silk.
30:14It's something kind of like the holy grail for material science
30:17in that it's extremely light and extremely strong.
30:20So we have materials that we try to do that in engineering today,
30:24like carbon fiber and Kevlar and other materials which are very strong and light.
30:29Spider silk is among that class of materials.
30:32The race to create synthetic silk for human applications is well underway,
30:37from superior antimicrobial bandages to environmentally friendly textiles.
30:42Imagine living in a world where we create bridges and highway infrastructure
30:46out of organic compounds and silk, you know,
30:48if we found a way to do what spiders do.
30:51That would be pretty unbelievable.
30:53While unlocking the secrets of spider silk remain elusive,
30:56we can only marvel at the incredible abilities
30:59of one of nature's most prolific builders.
31:03Ingenious builders are found everywhere in nature.
31:06Some have even had an influence on human shelter.
31:11If you've ever thought you've spotted huge haystacks hanging from tree branches,
31:15or even telephone poles, then you found a sociable weaver bird's nest.
31:21Built to house multiple bird families, the sociable weaver bird takes communal living to the next level.
31:27Nest building reaches its peak probably with the weaver bird.
31:31There are a lot of birds that weave intricate nests.
31:34Some have intricate structures that they use for kind of display or attracting mates,
31:39like bower birds as well.
31:40But nowhere does the actual nest, the egg holding structure,
31:45kind of reach the heights that it reaches in the weaver bird.
31:50Social weaver birds are quite different.
31:52If you look at the structures that they build,
31:54they look like haystacks suspended up in tree branches.
31:57This is similar to an apartment complex,
32:00where there's generations and generations of birds in there.
32:03These families stay in there,
32:05and their offspring might even move in next door at a different chamber.
32:09They continuously add on to it.
32:12Looking like a haystack or a grass hut up in a tree,
32:16these nests contain multiple chambers
32:18inhabited by bird pairs and their offspring.
32:21The entrances are underneath,
32:23which makes the nest look a bit like honeycomb from below.
32:26But the most impressive feature is that these nests are built to last.
32:32Some are even reported close to 100 years old.
32:39When you see a tree with a weaver's nest, they're very large.
32:44You know, we got 20 or 30 nests,
32:46and it's taking up 25% of this relatively large tree.
32:51We think of birds as only producing these little nests that sits in a nook of the tree,
32:57but the weavers are very much different in that they may colonize a very large portion of the tree,
33:01or you may see a tree that has 20, 30, 40, 50 weaver nests hanging off the branches.
33:07Each individual nest in itself is a pretty impressive structure in that the birds really do take time to use
33:17the strands of grass in specific patterns
33:20to construct a nest that is supported by the branch above,
33:26but has enough structural integrity to hold both the adults and the developing young in that nest without falling off.
33:35And the other great advantage of it is that because of the way it's hung off the branch,
33:40it's very difficult for predators to get to it without risking their own skin.
33:45But no matter how clever, sociable weaver birds are still vulnerable to predators.
33:51Snakes are very good at getting at weaver birds and getting into their nest.
33:55They can slither up the trunk, they can go to the end of the limb without trying to fall over,
33:59and they can get into the nest and really cause some havoc.
34:03Now recently there's been a new adaptation that weaver birds have actually figured out
34:07that snakes have trouble climbing telephone poles.
34:10And so they build their nests on telephone poles and snakes can't get at them.
34:15There are two types of weaver birds.
34:18The sociable weaver with their elaborate communal structures,
34:22and the solo weaver bird who builds an individual nest in order to attract a mate.
34:27But whether they want to go it alone or live in a commune,
34:31weaver birds are fascinating builders.
34:34There's a lot that goes into weavers building a nest.
34:37It's not just one skill.
34:40They have to have great visual acuity because they have to see the strands
34:44as they're weaving them together.
34:45They have to recognize that they're making patterns.
34:48That pattern may not be cognitive, the weaver may not be saying
34:52over, under, over, under, over, under, or what have you.
34:55There's something wired in their brain that says,
34:58okay, I'm at this point in the pattern.
35:00I got to now use my beak somehow and my eyes to make sure it matches this pattern
35:05and build a larger structure.
35:07In the world of birds, mostly it's females that do the majority of nest building.
35:11But in the weaver birds, males, for the most part, build these nests
35:15and then they use them as a way to kind of entice females to mate with them.
35:19And with the thought being that females will pick the most elaborate nests.
35:23At the start of courting season, the male weaver begins his nest
35:27by tying a single blade of grass to a tree branch.
35:31He uses his beak and foot to tie the knot.
35:35You start with one blade of grass, you put it in a spot,
35:39you test it out a few times, you see if it holds where it is.
35:42And like the course of building a nest, especially a complicated nest,
35:46may take a week, two weeks.
35:48And during that time, they're constantly maybe changing a little bit about the positioning.
35:53If early on in the process it's not quite right or it's not working out,
35:57they'll abandon that and try a different location.
35:59So it does change consistently and they are using inputs from the environment.
36:03It's not something that, bam, they make it in an hour and then they're committed.
36:06They're constantly reevaluating what they've done.
36:09The amount of effort they put into it makes them remarkable species,
36:13but also just shows how much investment they put in reproduction.
36:18Once the grass is secure, the solo weaver starts on the entrance to the nest.
36:25He continues building the structure by weaving the grass one strand over the other, in and out.
36:32The same way humans would weave a basket.
36:35It's surprisingly strong.
36:37The structures that they're creating and the way that they intertwine those fibers
36:42gives rise to some pretty significant load carrying capacity
36:47so that they're not at risk if they're young falling out
36:49and they're not at risk of that nest dropping off in a windstorm.
36:55Experience in weavers really plays a role.
36:58A yearling may not be able to build a strong nest because it's just learning.
37:02Maybe it's not as strong.
37:03Maybe it's not used to navigating, trying to build a nest from a limb in the wind.
37:09So as it grows and becomes older, the nest gets stronger and more solidified.
37:15Female weaver birds choose the best nest and settle in with the builder.
37:21Another way that weaver birds are actually quite unique in the nest building world,
37:25unlike a lot of other birds, is that most bird nests are just built to last a single season.
37:31Females will lay their eggs in their nest.
37:34The young will hatch in the nest.
37:35And then once they leave that nest and they make it out on their own, the nest is done.
37:39And they'll build an entirely new nest the next year.
37:42Weaver birds will live in their nests and around their nests all year sometimes.
37:48That is incredibly rare in the world of birds.
37:51And so these structures are designed not just to last for a short period of a couple of months,
37:55but to last sometimes for, like, lifetimes.
37:58Weaver bird structures bear a striking resemblance to grass huts.
38:03And that might not be an accident.
38:05They're the sort of structure that, yeah, a person could imagine living in.
38:10They look like pieces of the human built environment.
38:12There is some thought with weaver birds that human technology for home building,
38:17specifically with grasses and grass huts and things like that,
38:20did get some of their inspiration from the structures built by weaver birds.
38:24It's incredible to think that these remarkable birds
38:27may have been one of the early influences on how humans build shelter.
38:31But one of nature's most fascinating builders, the ant,
38:35is inspiring future technology.
38:38Ants usually conjure up images of tiny determined creatures
38:41tunneling underground and creating mounds of anthills.
38:45But there is one particular ant that is a different sort of builder.
38:48The army ant.
38:51Army ants are species that don't have a home.
38:54And so they move through the environment.
38:56They can be really quite vicious.
38:59They'll eat damn near anything in sight.
39:01They just go through as a horde.
39:03It's really rather gruesome.
39:06Army ants are wildly incredible.
39:08Like, the strategies that they have, especially to build on the fly,
39:12we think of them as this, like, super organism.
39:14Army ants build bridges using only their bodies.
39:17It's a very dynamic structure.
39:19There are always ants leaving.
39:20There are always ants coming in to join it.
39:22And it's continually lengthening or shortening or widening as is needed.
39:28And the ultimate goal here is to increase traffic flow.
39:32You know, you don't want to waste ants just making a bridge for the sake of it.
39:34The scale of the structures they're building are as large as freeway bridges that we would build.
39:40It takes us years often to design, construct, and put into operation these bridges.
39:47And yet the ants are coordinated enough to create that structure in minutes.
39:54The level of cooperation needed for such an operation is staggering.
39:58And the army ant manages it all on instinct.
40:01We're talking about an individual colony of ants that acts as this cohesive whole
40:06in a way that an individual person might act with that same level of agency in a lot of ways.
40:11So when you are an ant, what you have at your disposal are your numbers and your environment.
40:17It really shows that cooperation can take the place of innovation in some cases.
40:25Not only are the ants a super organism who's going out to get food, bringing back food,
40:30but they're also the road that these foragers are going across.
40:33I don't know any other organism that is not only the gatherer of food,
40:37but also the substrate that it's walking on.
40:41Evolutionary design has given army ants the ability to know when to start building a bridge.
40:46They've learned how to work together in a certain situation.
40:52Let's say you and I are in the front.
40:54We come to the edge, and you stop.
40:57Everybody walking behind you is not expecting you to stop.
41:00So as soon as they bump into us, we immediately freeze,
41:03and the others get on top of us, and they get bumped, and they freeze,
41:07so then it would go.
41:08It's not a, everybody wait, let me assess this, you know, maybe we can walk around.
41:12It's the innate freezing response of when I'm in front, somebody hits me, I stop.
41:19Once traffic slows down, the bridge ants rejoin the march.
41:23In order to maintain their efficiency as a colony,
41:26there cannot be too many ants involved in bridge building.
41:29It's almost like there's a program that's running all the ants together,
41:34but there's nothing there actually connecting all of that.
41:37So how do army ants know how and when to build?
41:41Pheromones are what are called info chemicals,
41:44and these are chemicals that exist in nature that provide information
41:47between individuals of the same species.
41:51What happens is that when you go out, and they have what are called foragers,
41:56and if they find food, then they will come back
41:58and they leave a marking pheromone on the ground,
42:01and it's sort of like a signal that says the food is fantastic,
42:05and so the others know to follow the trail the other way.
42:10Army ants have evolved to be nomads,
42:12constantly on the march foraging for food to feed the queen and larvae.
42:16They are so organized, they even have a three-lane traffic system
42:20that puts human highways to shame.
42:23These army ants are incredible kind of roadway engineers.
42:26Colonies can be up to a couple hundred thousand individuals.
42:29One of the things that they really strive to achieve is great traffic flow.
42:32When they're on the way to forage, they'll lay down some pheromone in the center,
42:36and then on either side of those are the returning ants.
42:39And so in this way, they know kind of which is the out way and which is the in way.
42:43This allows outgoing ants to turn sharply,
42:45while the returning ants who are carrying food back to the queen can maintain their path.
42:50But every once in a while, they have to stop.
42:53And once again, their fantastic building skills come into play.
42:56They make a temporary nest called a bivouac using their bodies.
43:00They build these living nests, these bivouacs, out of themselves.
43:04Older ants are near the edges, so they're a little more exposed
43:08in case there is a danger. Younger ants are closer to the middle.
43:10And within that, they have tunnels to go through.
43:13They have places where they bring the food.
43:14They have the queen, who is producing eggs and being fed.
43:17And they have this entire living nest that can adapt to stimuli around it
43:22as ants rear up to any threat that might present itself.
43:24It just goes to show without any individual sense of danger or fear.
43:30There's a lot that's possible.
43:32And they do come up with like weird, amorphous living shapes.
43:36And it's so interesting.
43:39The amazing engineering and building skills of the army
43:42has made them an evolutionary powerhouse.
43:46It's incredible because we think we're the major life form on Earth.
43:51We got another story coming to us.
43:53These guys out biomass us by orders of magnitude.
43:57We think of us as being more evolved, but the way they work together
44:01has allowed them to be on Earth for thousands of times
44:05that humans have been here.
44:07And that's something we want to do as engineers
44:10is have a modular design of adaptable systems
44:15that recognize that they need to change to the inputs
44:18that's coming into them.
44:20It's much like the ants in the colony do.
44:22But we're not there yet.
44:24I mean, that's complexity beyond what we currently have today.
44:31Evolution has clearly gifted some members of the animal kingdom
44:34with incredible construction skills.
44:36We can learn a great deal about sustainable landscapes
44:39from the beaver, circulation and airflow from mound-building termites,
44:43and the beautifully symmetrical hives of the honeybees.
44:46We are already trying to mimic the strength of spider silk.
44:49The sociable weaver bird may have inspired the first human huts.
44:53And we can only dream of one day building like army ants.
44:57These animal builders inspire on every level
45:00with their incredible creations.
45:23The mi advice and the earth ecosystem is a very average Maria
45:28for once in months.
45:30They take around that very long space.
45:30How?
45:30When the event began to develop a marinefelden chercher
45:31There you go look at ADOL的話
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