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the animal within s01e06
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00:00Fireflies, Komodo dragons, and the blue-ringed octopus.
00:04These are the mad scientists of the animal world.
00:07Many produce toxic substances to ward off predators,
00:11and the most dangerous creatures on the face of the Earth
00:13have mastered DIY chemical warfare.
00:16Yet others can caught potions to protect themselves,
00:19or to woo mates or prey.
00:21Imagine if we could use our own bodies as chemical labs.
00:25These creatures have devised ways to do just that,
00:28yielding very powerful results.
00:50One of the most potent examples of biochemistry
00:53is found on a group of Indonesian islands.
00:57Whipped up by a fairytale-like creature,
00:59it's got scientists wondering whether an untapped source of antibiotics
01:02might be dragon's blood.
01:05Komodo dragons are the closest things to real dragons that we really have.
01:10The name does not lie.
01:11I mean, I wonder where the human concept of a dragon came like,
01:15and how much of it was impacted by creatures like that.
01:18Feeding on deer substantially larger than it is,
01:20the Komodo dragon is an apex predator,
01:23which measures up to three meters in length,
01:26and weighs up to 150 kilograms.
01:29But how does it hunt exactly?
01:30The Komodo has a long yellowed forked tongue,
01:33with which it can detect carrion up to nine kilometers away.
01:37Similar to a lot of other reptiles,
01:38the Komodo dragon has this Jacobson's organ,
01:40and so it'll stick out its tongue,
01:42and it'll kind of smell the air through its nose,
01:45and its hearing is not super great.
01:47But it doesn't need to be for this animal.
01:49It's thought to be less important for them
01:50to kind of sense things around in their environment
01:52than it would be for, say, vulnerable deer
01:55that also lives on the Komodo island.
01:57The world's largest lizard hunts in the afternoon
02:00and prefers ambushes.
02:02Their metabolisms are still relatively slow.
02:04As reptiles, they're ectotherms,
02:06and so they're warmed by the surrounding environment.
02:08Their body temperature stays very close
02:10to the surrounding environment.
02:11And so they need to bask in the sun like any other reptile.
02:13They tend to eat, you know,
02:15up to 80% of their body weight in one sitting,
02:17and then they might not eat for another month.
02:19And so often they'll only eat, you know,
02:21a handful of meals throughout the whole year,
02:22and that's enough to satisfy them.
02:24So they have these really low metabolisms
02:26that allows them to live for quite long times.
02:28What happens with a metabolism is it reflects the energy sources
02:32that are available to you.
02:33So they live in a confined area.
02:37There aren't any opportunities to find new places
02:39to kind of find provisions or food sources.
02:41If you are an endotherm on a cold day,
02:44you're not able to, you know, to create the energy
02:46and to move at the speed that you need
02:49in order to kill these mammalian warm-blooded prey.
02:51Komodo dragons, they can just kind of sit and wait
02:53until they have enough energy.
02:54The opportunity, you know, has come at the right time.
02:56It's a testament to kind of the environment that they live in,
02:59giving them what they need.
03:00The Komodo dragons will usually swallow
03:02their entire prey whole.
03:03They have these loosely articulated jaws
03:06that allow them to stretch to quite a high degree
03:08and fit an animal much bigger than the size of its head
03:11into its mouth.
03:13And they're often hunting large creatures,
03:15so it takes a long time,
03:17sometimes, you know, up to half an hour.
03:19And then you can imagine things like boa constrictors
03:21doing similar things with their prey items.
03:23It can be difficult to breathe as you're doing that process,
03:26so they have this tube under their tongue
03:28that allows them to breathe
03:30as they're kind of slowly imbibing their large prey items.
03:34It's like a little snorkel under their tongue
03:36that allows them to eat and breathe at the same time.
03:38And when the going gets really tough,
03:41it has yet another ability at its disposal.
03:44When it starts to have difficulty swallowing a large prey,
03:48then it'll actually ram itself against a tree
03:50to force that down its throat.
03:51And these creatures are tough on the outside.
03:54It takes Komodos eight or nine years to mature,
03:57and they'll live to be about 30.
03:59You can tell their age by the extent of their osteoderms.
04:03Their skin is covered in these osteoderms,
04:05which are these bony plates at the surface of their skin.
04:08And so it's essentially kind of a chain-mail armor
04:10that surrounds them, so they can be incredibly well protected.
04:13The Komodo also has powerful neck muscles
04:16and incredible teeth that come into full effect
04:18when it lunges at prey.
04:20Because they have, you know,
04:21these 60 serrated steak knife teeth in their mouth,
04:25growing up to 2.5 centimeters long.
04:27I mean, that's absolutely massive.
04:30The Komodo has yet another trick up its sleeve.
04:33Venom.
04:34But this is no ordinary venom.
04:36It is a masterstroke of biological chemistry
04:39that ensures the Komodo unparalleled dominance.
04:43Clearly, this is not something
04:44that's necessary for their survival.
04:46It's a little bit of an icing on the cake sort of a situation
04:48from an evolutionary perspective.
04:50The Komodo is the largest venomous reptile.
04:53Whereas snakes usually have one venom duct,
04:56the Komodo has two venom glands
04:58in their lower jaw between their teeth.
05:00This venom just kind of secretes itself into the saliva,
05:03and so it's not nearly as efficient
05:05as kind of the hypodermic needle of a venomous snake.
05:08But it is, especially considering kind of their method
05:11of biting things, leaving incredibly large wounds,
05:14it's pretty effective in its own right.
05:16The toxic brew of protein
05:18stirred up by the Komodo's venom glands
05:20is not as fast acting as other venoms in the world.
05:23But it is perfect for the dragon's purposes.
05:27One protein in the venom
05:28relaxes the cell walls of the prey,
05:30widening blood vessels
05:32and causing blood pressure to drop,
05:34which ultimately induces shock.
05:36And the venom is also an anticoagulant,
05:39which prevents the prey's blood from clotting.
05:41Venom's an amazing tool for animals,
05:43and it's so widespread in the animal kingdom,
05:46it's absolutely amazing,
05:47which means it's a very successful approach
05:50to killing things.
05:52There's almost no chance of escaping in a lot of ways.
05:54When you, as a predator, like a Komodo dragon,
05:58have an incredibly powerful down bite,
06:00and you have a physiology kind of of your jaws
06:03and the shapes of your teeth as well,
06:05that don't create like a clean cut,
06:08but create kind of a serrated, jagged wound,
06:11that's already a lot more difficult for healing purposes.
06:14And then these toxins in their mouths will increase the bleed out,
06:18they'll act as anticoagulant so the balloon can't heal itself,
06:21and they'll lower the blood pressure of the animal as well,
06:24to keep blood flowing.
06:25It's absolutely a devastating bite,
06:28and probably the worst thing to be bitten by in the animal kingdom.
06:32Having an advantage like venom where you can just strike
06:35and then sit back, wait for the animal to die
06:38without putting yourself at risk is a huge advantage.
06:41If you're a cold-blooded animal, an endotherm,
06:44you know, you have a limited supply of energy
06:46and you can't expend it for really long periods of time,
06:49so having a venom that subdues the prey relatively quickly
06:53so that you don't run out of that immediate energy source,
06:56and then you're able to consume your prey at your leisure.
06:59In 2009, scientists finally discovered
07:03the killer chemistry of the Komodo's venom.
07:05The venom of the Komodo dragon was a mystery, actually,
07:08for a really long time.
07:09For the longest time,
07:10we just thought that they had incredibly dirty mouths,
07:13and there was a lot of bacteria inside these mouths
07:16that when they bit got transferred into wounds
07:18and caused kind of these anticoagulatory properties
07:21and increased damage in bites.
07:23With over 50 varieties of bacteria in the Komodo's mouth,
07:27we thought any creature it bit would die of infection.
07:31When we learned that it was using venom versus bacteria to kill,
07:35this probed yet other questions.
07:38We've always wondered why Komodo's themselves never fall ill
07:41or get infected,
07:42despite frequently sustaining wounds themselves.
07:46They're highly hostile and dangerous to one another.
07:50So, and I guess, in a way,
07:51that's really akin to how people live in the world, too, right?
07:54Like, that's what's most dangerous to people.
07:56Our other people, same with Komodo dragons.
07:59They're really, like, the humans of their environment.
08:01You know, this apex predator
08:02that's really just become a danger to themselves.
08:05Dragon battles are often lethal.
08:07But when they're not, Komodo's heal remarkably well.
08:12In a world on the hunt for resistance-free antibiotics,
08:16we wondered whether this fairytale-like creature holds a key.
08:20And in 2017, a substance was isolated in the Komodo's blood,
08:25which appears to have supercharged antibiotic properties.
08:28Currently being studied, biochemists have dubbed it DRGN1.
08:34Animals always seem to have some chemical specialty
08:37that allows them to fit into some kind of niche,
08:40whether we can see it or not.
08:42Every animal kind of has some organic compound
08:45that's unique to it that it produces to make itself better
08:49or protect it from something.
08:51And as engineers and scientists and chemists,
08:53we're constantly looking to the animal kingdom
08:57for better ways to make new compounds
08:59that may have medical applications
09:02or materials engineering applications
09:05because the biology of life is so complex,
09:09it can just produce compounds
09:11that we can't even dream up yet.
09:13As the Komodo was working its magic
09:15on Indonesia's Sunda Islands,
09:17over in the Americas,
09:18a more ordinary creature
09:20is concocting a potion of its own.
09:23Skunks are the real stinkers of the animal kingdom.
09:26Although they'd certainly lose most physical fights,
09:29they have an uncanny ability to scare away their opponents.
09:33All thanks to an arsenal of chemicals
09:36they store in their rear ends.
09:38I like to tell my daughters that the scariest thing
09:40in the forest is the skunk.
09:42And it's one of the few animals that will stand his ground
09:45and make sure that you're the one who runs away
09:48rather than them running away.
09:49Skunks are, you know, one of our cutest animals
09:52that's also incredibly maligned just because of something that it does,
09:56which, by the way, is not dangerous at all.
09:58It's a testament to the power of a smell.
10:01It can't physically hurt us, but it annoys us
10:03and puts us in discomfort to the point where we, like,
10:06have a visceral reaction to the sight of skunks in our communities.
10:10Skunks are a mammal only found in the Americas,
10:12and the most iconic of them, the striped skunk,
10:15lives in the U.S., Canada, and Mexico.
10:19Originally, they were classified under mustelids,
10:22where otters, the weasels, martins.
10:24However, they have been reclassified to their own group, mephididae.
10:27Skunks are omnivorous, eating plants and animals.
10:31Like raccoons, they are easily habituated to living near people,
10:35which has enabled them to thrive in urban and suburban areas.
10:39In urban environments, they've flourished
10:42mostly because we have these beautiful, pristine lawns
10:45that they love to dig up to get at the grubs underneath our grass.
10:47They're known as your lawn ruiners,
10:50eating the invertebrates found in your lawn,
10:52but they can eat anything that they can get their hands on,
10:55from roots, berries, veggies, and meat.
10:58Among the animals that prey on them are domestic dogs,
11:01coyotes, bobcats, and owls.
11:04But even their predators tend not to prefer to go after skunks.
11:09Their defense is one of nature's most effective stink bombs.
11:13The skunk creates a noxious chemical in its anal gland,
11:16and when it's frightened or angered,
11:18it sprays this out of its backside
11:20with impressive accuracy and distance upon its target.
11:24The chemical itself is a combination of six thiols and one alkaloid.
11:30Thiols are a chemical of sulfur and hydrogen bonded together.
11:33There's a lot of thiols subtly in a lot of different organic things,
11:38and they're in onions and garlic in small amounts.
11:42This is what makes garlic smell, and onions cause our eyes to water.
11:47Thiols are particularly obnoxious compounds,
11:50and we actually use them in engineering quite frequently
11:53where we need an odorant.
11:55So in propane or natural gas, you may have noticed that it has a smell
11:59kind of like rotten eggs.
12:00Well, that's a thiol called mercaptan that we specifically add as an odorant
12:06so that you can smell the natural gas of the propane,
12:09which naturally has no odor.
12:11So very similar to the skunk's odor,
12:13we're actually using similar compounds
12:15to make sure we're protecting people from natural gas and propane leaks.
12:20In skunk spray, three of the thiols are regular,
12:23and the other three are thioacetates,
12:26which don't have a strong scent on their own,
12:28but do when they react with water.
12:31The spray is an oily substance.
12:33That's why it clings onto you and lasts for a long time.
12:36When dogs get sprayed by skunks,
12:38you're usually advised to actually not bathe your dogs
12:40because when you bathe your dogs,
12:42you're allowing that substance to react with water
12:44and allow it to become smellier.
12:46And to combat this, it's suggested to use baking soda
12:50or hydrogen peroxide as it configures the chemical structure
12:54to that non-putrid smell.
12:58Side effects of getting sprayed with skunk thiols
13:00can be vomiting and temporary blindness.
13:03If ingested, these chemicals are poisonous
13:05and can even kill predators.
13:08The skunk carries enough spray for five or six uses,
13:11about 15 milliliters.
13:13The chemicals are constantly being concocted,
13:16but it's a slow process.
13:18It takes ten days to refill the gland.
13:21I like to picture the little scent gland of a skunk in its body.
13:25It's around the size of a grape,
13:26and you picture this tiny little thing
13:28having this amazing effect on such a large area.
13:30What they actually do is they have nozzle-like protrusions
13:34where they can regulate the way that it is sprayed.
13:36So they can spray in a mist, or they can even use a continuous stream,
13:40and they can shoot up to far distances with high accuracy.
13:43They have been recorded to do at a distance of over six meters.
13:47The ability to spray a liquid a relatively far distance
13:50is really dependent on the nozzle size and the volume of the container.
13:54So imagine taking a bulb with a really small hole in the end
13:59and filling the bulb full of liquid and then squeezing the bulb.
14:01You're going to be able to squirt the water out the small hole a long distance.
14:05Well, the skunk's essentially doing the same thing,
14:07is that they have a small orifice that releases the stinky liquid,
14:11and then they have a relatively large bladder with a muscle around it
14:15that squeezes it, giving them that six-meter distance.
14:18There's not many creatures that can propel something out of their body that far.
14:24That six meters distance was a real big safety zone for the skunk,
14:29so a really, really great evolutionary advantage
14:31to prevent it from being killed by its predators.
14:34Despite how effective this defense is,
14:37given that it's always in short supply,
14:39the skunk is not quick to use it.
14:41If you are a skunk and you only do have one defense,
14:44and it is your spray,
14:45you can't go around dispelling all of your spray,
14:48and then you are completely defenseless for up to two weeks
14:51as you build up more.
14:52Before using its spray, the creature has a few warning strategies.
14:56One of those is the stripe on its back,
14:59which is like an arrow that points to the source of its poison.
15:02We normally find that in nature
15:04when there are bright colorations or distinctive patterns.
15:07those are normally advertising that an animal is venomous or poisonous,
15:12and in the skunk's case, that they secrete the smell.
15:16As well as the coloration of the striped skunk,
15:18all species make gestures to ward off a threat before spraying.
15:23They'll kind of stand on their front legs and do these kind of headstands.
15:26I find them really interesting because they don't, in fact,
15:29resemble any other threat display from an animal that could actually harm you.
15:33They are unique to skunks, and they're all to just kind of show off the fact,
15:37they're like, look, I'm a skunk.
15:38And it does work for them because we treat them with a lot of respect,
15:42a lot of distance, and in some cases, a little bit of fear.
15:46In fact, the skunk's chemistry has been mimicked by human defense systems
15:50to instill fear and distance.
15:53Created in the 2000s by the Israeli army,
15:56the skunk bomb is a synthetic crowd control measure
16:00modeled on actual skunk spray.
16:02It's designed to permeate victim clothing for up to five years.
16:07If you spray it onto clothes or something like that,
16:09it will hold that odor for a long time.
16:11So, you know, potentially as a weapon, as something that's going to be noxious to people,
16:16it will definitely work.
16:17You know, it really does have a strong biological reaction.
16:21Luckily for the skunk, the noxious perfume it produces
16:24is enough to keep humans and animals away and ensure its success.
16:31While the skunk's chemistry is a repugnant repellent,
16:34an even smaller animal produces a far deadlier concoction.
16:40While it lounges in the shallow waters of the Indian and West Pacific oceans.
16:44Blue-ringed octopus, really incredible, tiny creature, small,
16:48really stunningly beautiful, really intricately patterned,
16:51and one of the most lethal animals on the face of the planet.
16:55Blue-ringed octopuses are about the size of a ping-pong ball,
16:58but one bite from a blue-ringed octopus has enough venom to kill up to 26 humans.
17:03Fortunately for us, before we get too close to them,
17:07they flash the blue rings they are named after in order to warn us away.
17:12This incredible creature lives in tidal pools and coral reefs
17:16from Japan to Australia.
17:18They grow to be between only 12 to 20 centimeters,
17:21but are generally docile in nature.
17:24Cephalopods, cuttlefish, octopi, squid, etc.
17:26are just this really unbelievable group of organisms.
17:30We know that they're quite intelligent.
17:32We know that they have problem-solving abilities.
17:35They are also masters of escape,
17:36and they can even learn to communicate with us in some ways
17:39through the arsenal that they have available,
17:42through their color patterns.
17:43And what's really amazing is that most of them have incredibly short lives.
17:47So the fact that they're able to, you know, create this intelligence
17:52over, like, a lifespan that in most cases is no longer than two years
17:56is really unbelievable.
17:58If threatened or provoked,
17:59this octopus turns bright yellow with flashing blue rings.
18:03The blue rings are kind of interesting.
18:05They're created as sort of an iridescence type of light.
18:09The iridescence is actually hidden under a muscular layer,
18:12and then there's chromatophores around that layer that can control
18:16how bright that iridescence is.
18:18So that muscular layer will contract.
18:21It'll allow that iridescence to come out,
18:24and you'll see the blue ring.
18:25The rings contain multi-layer light reflectors called iridiphores.
18:30The iridiphores have this refractive quality that reflects these light
18:33and can actually appear to be changing in color
18:36depending on which angle you look at them.
18:38And in their relaxed state,
18:40they're covered by certain muscles that when they contract
18:43they expose their iridiphores.
18:45As with the skunk's white stripe,
18:47or the firefly's bioluminescence,
18:49the coloration is a warning sign.
18:52So by being brightly colored,
18:54you can warn potential predators to recognize you quickly
18:57and effectively that they won't confuse you
19:01with something that's more palatable.
19:02They will know instantly by looking at you,
19:04you're very unique, you're very distinctive,
19:06they don't want to touch you.
19:07And in that case, that uniqueness means I am very dangerous.
19:10Its second line of defense,
19:12if you are naive enough to disregard its blue rings,
19:15is its extremely lethal venom,
19:18one of the deadliest biochemicals in the animal kingdom.
19:21Their toxin is so potent,
19:23it's a thousand times more potent than cyanide.
19:26The toxin found in the blue ringed octopus is called tetrodotoxin,
19:30and they actually theorize that they find these toxins
19:33from the food that they eat.
19:35They actually don't make themselves,
19:37but it's made by the bacteria living in their salivary glands
19:40that produces it for them,
19:41and then deliver it through the bite of their beak.
19:44Tetrodotoxin is the same neurotoxin found in pufferfish,
19:47porcupinefish and starfish,
19:49which blocks the sodium channels in its victim,
19:52causing blindness and eventually death.
19:54At first, a toxin can cause delayed motor coordination,
19:58and then it attacks your respiratory system,
20:01basically paralyzing you and depriving you of oxygen.
20:05There have been records of human fatalities,
20:07and there is no cure.
20:09However, you can actually help the person surviving
20:12through artificial respiration.
20:13It almost seems like a case of evolutionary overkill
20:16until you kind of look at it a little bit more carefully.
20:18If you're a small creature that's evolved to have this, like,
20:23incredible toxic punch,
20:24it's probably because the things that are preying on you are enormous,
20:28and so you need to be able to be dangerous
20:31to something that's much larger than yourself.
20:33While it can be used for defense,
20:35the primary use of this super chemical is for hunting.
20:39Blue-ringed octopuses prey on small crabs and shrimp,
20:42and they use this venom to target their prey
20:44and uses their beak to deliver their venom onto their prey
20:48as they're penetrating their shell,
20:50and that's how they actually end up
20:52being able to overcome and subdue their food.
20:55The lethal neurotoxin can paralyze prey within seconds.
20:59As with so many chemicals cooked up by the animal kingdom,
21:03scientists and engineers are researching
21:05whether the blue-ringed octopus's venom could be used strategically.
21:09When you're looking at their toxins
21:10and their ability to delay these motor coordinations
21:14and affect the nervous system,
21:15you can study how you can use that for some treatments for pain.
21:20Other medicinal uses could be in the treatment of allergies and cancer.
21:24Like the Komodo dragon's blood,
21:26the neurotoxins of cephalopods
21:27remain an untapped resource in drug discovery.
21:31There's another creature scientists look to for answers about compounds.
21:36Like the blue-ringed octopus,
21:38it too uses its body as a chemistry lab,
21:41but in a much flashier way.
21:43Under a clear exoskeleton,
21:46the firefly triggers chemical reactions to create light.
21:49The light shows can be used to repel predators and attract mates,
21:54and they can also be weaponized to shocking effect.
21:57What fireflies do is they create this, like, beautiful aesthetic experience for us,
22:02and we forget about the context of that behavior
22:05from the creature's point of view itself.
22:08They are in, like, the fight of their lives
22:10to attract mates and defend territories.
22:13Fireflies are beetles,
22:15nocturnal members of the Lampiridae family,
22:17that comprise more than 2,000 species,
22:20and normally feed on nectar and pollen.
22:22Meanwhile, a vast number of predators try to feed on them,
22:26including spiders, toads, frogs, bats, birds, mammals, and lizards.
22:32Firefly species have this defensive steroid molecule called lucifabagin
22:36that can be quite unappealing to a lot of predators,
22:40like bats, lizards, some birds, and can make them gag.
22:43In conjunction with producing the toxic-tasting steroid,
22:47it is thought that the fireflies' ability to light up,
22:50called bioluminescence,
22:51began as a means of warning away predators.
22:54Similar to how skunks would alert their predators that,
22:58hey, I have this putrid odor that I will spray onto you,
23:01the fireflies advertise to their predators,
23:04I'm distasteful, I do not taste good at all.
23:06It's called aposomatic, or warning coloration.
23:09So, you know, many, many snakes that are very toxic
23:14are often red and black or yellow and black.
23:17It's telling you, don't come anywhere near me, you may regret it.
23:21We are familiar with seeing fireflies glow as they fly,
23:24but it is something they can do even as larva.
23:27So, you're larva running around, and some bird wants to eat you,
23:31and you take this position where all of a sudden your rear end comes up,
23:35a bit like scorpion-like, and at the same time it glows.
23:39Quite impressive.
23:40Probably deters something initially enough for it
23:42to give it a split second to maybe scamper away.
23:46How exactly does the firefly make its warning light?
23:50Bioluminescence is really quite cool.
23:51I mean, it's surprisingly prolific throughout the animal kingdom
23:55that shows up in many different sea creatures.
23:59In not just simple life forms, but in complex life forms like fish and octopus.
24:04As lay people, we don't see light as a byproduct of chemical reactions.
24:10It is.
24:11It's just not that common, and it's not in our everyday occurrence until we see it.
24:16Chemical reactions all release energy.
24:18Most of the time we think of those chemical reactions producing heat as a byproduct.
24:23When we stick two things together, we get foaming and we get boiling.
24:28But a lot of chemical reactions are much more subtle, producing new compounds,
24:32and in some cases, producing light.
24:34When you think of light, you think of heat.
24:36But if that were the case with fireflies, they would simply overheat and die.
24:39So that's why the reaction of light is actually through chemical compounds
24:42that they have in certain organs of their body.
24:45They emit light through their clear abdomen.
24:47That allows them to show the reaction that is going inside their body.
24:52The light that is produced in their light organ is the result of a chemical reaction at the cellular level,
24:58between luciferin and oxygen, catalyzed by luciferase.
25:03When luciferase, calcium, adenosine and triphosphate, also called ATP, come into contact with oxygen,
25:10it oxidizes and creates a new molecule that is highly unstable.
25:15The molecule quickly breaks down, releasing light energy as it does.
25:19Luciferin is an organic compound.
25:22ATP is the energy source in the cells, and oxygen is always in biology there to extract energy.
25:29We're always oxidizing our fuel energy.
25:32The last component is an enzyme, and enzymes are really neat compounds in biology
25:36in that they don't actually participate in the reaction, they just help it happen.
25:42So without the enzyme, the reaction goes very, very, very slowly.
25:47And you would get a little bit of light.
25:49But when you provide the enzyme, the reaction goes very, very, very fast,
25:54and all of a sudden you get that bright blink.
25:56So it's a really neat biology because it's not just a single compound that the firefly is producing.
26:03It's a compound, an enzyme, the energy storage, and still the oxygen that is breathing from its environment,
26:10all have to come together and have a relatively rapid reaction to get this volume
26:15or this intensity of light produced from the firefly.
26:19As if chemically causing oneself to glow is not enough,
26:23fireflies take bioluminescence to a whole new level.
26:27These animals not only emit light but can actually modify it,
26:30and each species has its own unique pattern.
26:32You can almost say they have different languages.
26:35It would be the equivalent of Morse code.
26:38So one species may produce a signal that is a flash of light just one at a time.
26:44Just flash, flash, flash.
26:47And then there are others that might go two short flashes and a long flash.
26:52While they first evolved bioluminescence as a warning light to predators,
26:56this amazing bug then adapted the capability to flash its light
27:01in order to attract mates.
27:03So each one has a signal.
27:05It's a bit like pheromones.
27:06Each species responds to its own chemical message,
27:12in this case the same light signal.
27:15There's a strong selection to have a different signal than the other species around you
27:20because you don't want to mate with the other species
27:23because the offspring, if they survive, are usually inferior.
27:28And given that the firefly only reaches sexual maturity in the last two weeks of its two-month lifespan,
27:35its ability to flash in code is an extremely fortunate design tweak.
27:39It needs all the help it can get.
27:41Game on. As soon as a firefly is in that stage of its life cycle,
27:46it has to attract a mate.
27:47It is all bets are off and that's what they're doing.
27:50I have two weeks and I have to do this thing that will assure my genetic legacy.
27:54There is no room for relaxation, I think, in that life.
27:57In terms of controlling the light patterns or the beginning and ending of each chemical reaction,
28:03the firefly does two things.
28:05First, it can control the muscle that transports the oxygen to the light organ.
28:11Secondly, it again puts its chemist hat back on and has the light organ produce nitric oxide,
28:16which intensifies the chemical and, therefore, light energy process.
28:21Chemical reactions are difficult to control at the best of the times
28:25and we have entire specializations in chemistry and engineering,
28:30trying to make sure reactions happen in a really tight framework
28:33so that it doesn't go too fast and doesn't take too much energy and doesn't go too slow.
28:38But somehow the firefly has this built-in mechanism that allows it to very carefully control that reaction chemistry
28:47and control it consistently to do, you know, a repeated flashing at a specific frequency,
28:51which is almost mind-boggling.
28:53It just amazes me how biology will find a way.
28:56Beyond using bioluminescence to repel threats and attract mates,
29:00one species, dubbed the femme fatale, uses it as a truly dark art.
29:06A guy called Jim Lloyd first discovered it,
29:08and basically what happens is that a female, when she's trying to attract a mate of her own type,
29:16let's say she has three short beep-beep-beep,
29:19and then all of a sudden he noticed that she suddenly changed and was going beep-beep-beep-beep,
29:25which was another species signal.
29:27And he's going, what the heck happened here?
29:30And what she's doing is she's attracting the males in, and then she actually eats them.
29:36It's like delivering a pizza, you know, I don't go out and look for it, I'll bring it to me.
29:40They actually can harvest the defensive steroids found in those animals
29:44and use it to their own advantage and pass it on to their offspring.
29:47Ultimately, being even more toxic due to the increase in leucidophagins,
29:52the femme fatale has a much better chance of being spit out if she finds herself in the mouth of
29:57a predator.
29:58And whether for safety, sex or cannibalism,
30:02bioluminescence in the firefly has taken at least a hundred million years to evolve.
30:06It's not surprising that scientists have wondered about human applications.
30:10What the firefly is doing is essentially exactly the same thing as the LED lightbulb.
30:16The LED lightbulb is doing it with a transistor and electricity,
30:21whereas the firefly is doing that cold process using a chemical means.
30:26But really, really similar in terms of what's happening at the atomic scale.
30:30While harvesting fireflies for free light is impractical,
30:34the firefly's luciferin chemistry has inspired a new method of whole-body imaging.
30:40Recently, a gene that encodes firefly luciferase was introduced to a mouse
30:45and used to monitor the growth of a brain tumour.
30:47And we're using it in DNA for markers so that we can tag certain genes and know where they are.
30:54And that's the crazy thing about biology to me,
30:57is that every single physical phenomena we find as engineers and scientists,
31:01somehow biology has always beaten us to it.
31:04And that's why we also look to biology for inspiration,
31:07because there is where all the information lies.
31:11Another place animals are working chemistry magic is in the riverbeds of Africa.
31:16Only recently discovered, scientists are taking a closer look at what appears to be nature's most advanced skin cream.
31:23Although the task is much easier said than done.
31:26Hippos are considered one of the most dangerous animals on our planet and have very little threats that they are
31:34going to be facing.
31:36Perhaps a brave crocodile might go after a young hippo, but it is a lot of risk to take on
31:42this feat.
31:42We think of them as like lumbering, slow, kind of dim creatures in a lot of ways,
31:48but that could not be further from the truth.
31:51The main reason hippos have few predators is their size.
31:55They stand between three and four metres high, or nine and a half to fourteen feet,
32:00and they weigh 1,300 to 3,600 kilograms.
32:05I mean, when you're a hippo and you weigh, you know, a ton, and you're huge,
32:09you have a lot of kind of physical power to kind of back up your aggression.
32:14Extremely territorial, they not only fight off other species,
32:17but frequently other hippos that enter their territory.
32:21I was on safari, we were on the boat, and I heard my wife beside me scream,
32:25and out of the bushes beside the boat charged a hippo with his mouth wide open and bumped the boat.
32:30But the hippo bumped and backed down, and we were all okay.
32:33I got a good look at the hippo, and one of the things I noted was that
32:36he'd obviously been in a major fight.
32:39They're often very heavily scarred, and they have huge scars all over their body from their fights.
32:43When you do see videos of hippo fight scenes where you have the males with their mouths open,
32:49you know, almost 180 degrees wide open with these huge tusks battling each other,
32:55and those tusks often gore each other and cause large wounds on the skin of the hippopotamus.
33:00Still, there is another danger the Sub-Saharan native always faces.
33:05I guess their greatest enemy is the sun.
33:07I mean, a lot of things that live in Sub-Saharan Africa with hippos have, you know,
33:12adapted to the fact that the sun is so bright and powerful in those areas
33:15by kind of living in environments where that's blocked out, by living kind of under forest canopies.
33:20But hippos live in exposed pieces of river where there aren't trees covering them,
33:26and they are more exposed than a lot of other creatures.
33:30Although hippos are semi-aquatic and spend most of their life submerged in water,
33:34they prefer to stay on their feet.
33:37Hippos were fondly nicknamed river horses by the Greek when they first encountered these species,
33:42and they actually cannot swim very well because of their very dense body shape.
33:48They actually just kind of push themselves from the bottom in shallow areas
33:52and almost look like underwater ballerinas.
33:55And they might spend the entire day lounging in the sunny riverbanks,
33:59for this herbivore typically grazes in the evening when it's cooler.
34:04The sun is a driving force of life on our planet but also has destructive properties,
34:09especially the radiation that it brings into our atmosphere.
34:12One of the things about solar radiation is it comes in different wavelengths.
34:16What we see is the visual spectrum, so red, green, blue, orange, yellow, etc.
34:22But beyond the visible spectrum at the higher energy levels is UV light, ultraviolet light.
34:28And ultraviolet light behaves with biological systems a little bit different than visual light.
34:32The energy in the photons of the ultraviolet light is so high that it can start to break down the
34:38proteins in our body
34:39and break down the compounds and cause damage.
34:41And in fact, the UV light can actually break down DNA and lead to mutations and cancer, etc.
34:47So that UV spectrum in the light coming from the sun can actually be quite dangerous,
34:52especially an animal in the Serengeti.
34:54They have very long dry seasons, very low moisture in the air.
34:58If you're not heavily furred, you need to have some mechanism to protect you from the sunshine.
35:04As humans, we have certain adaptations, although it is quite limited.
35:08We can produce a melanin in our skin, which is a pigment that allows a scattering of these UV radiation
35:14and prevents the absorption into our skin.
35:17However, some animals have developed ways that they can actually produce some compounds
35:21similar to the products that we use for sunscreen and sunblock.
35:24Of course, hippopotami can't produce sunscreen. Or can they?
35:29The answer might be yes.
35:31Nature has come up with this amazing solution to a lot of the problems that hippos face
35:36just by, you know, being in the beating sun for so long.
35:39Their pores and their skin secrete this red substance, which actually acts as a sunscreen,
35:46which, you know, blocks the UV rays of the sun and protects them.
35:50When the hippo emerges out of the water, they appear to sweat a rust-colored pigment.
35:55It's not true sweat, because the hippo does not actually have sweat glands.
36:00But it has other glands just under the skin that produce this special thick oily substance,
36:05which it then releases through the skin.
36:07It consists of two acids and a mucus, or hipposidoric acid, is orangish in color and acts as a sunscreen.
36:16The red compound that the hippos release is a compound that specifically absorbs UV light,
36:22so it doesn't get to the underlying skin cells.
36:25So there are two different approaches we use for human sunscreen.
36:27We use blockers. So those will usually be a zinc oxide material that is an inorganic,
36:34so it's basically a powdered, almost like a paint material.
36:38And the other one is to use organic compounds which specifically absorb UV light in specific spectrums.
36:44The hippopotamus' UV protection that it secretes from glands on its body is the latter.
36:50The second acid, hipposidoric, is red in color and acts as an antibiotic.
36:55Not only do they get this great secretion that protects them from sunshine,
36:59because they're such prolific fighters and get a large number of wounds,
37:03that same compound also protects them against infections when they are injured.
37:09Lastly, the mucus helps to keep the skin moist when they emerge from the water,
37:14which is good because the hippo's skin is easily dehydrated,
37:17part of the reason it likes to bathe so much in the first place.
37:20They have kind of an all-in-one substance that, you know, acts as a sunscreen,
37:24acts as an antibiotic, and also acts as a moisturizer.
37:27They're all like a beauty boutique all-in-one.
37:29It doesn't come as a surprise that some of the chemical companies interested in the hippo's special source
37:35are skincare manufacturers.
37:37If they could crack this code for human skin, it could be priceless.
37:43Yet, ironically, this compound that evolution has perfected over eons for the hippo
37:48would be of no value to its closest relative.
37:51Hippos are actually the closest relatives to cetaceans and whales,
37:55and they're actually thought to diverge from a common ancestor.
37:58Being that the whales, other cetaceans moved into the water,
38:02they have protection from the sun by being underwater.
38:05However, hippos had to develop their own adaptations to protect themselves from being under the sun.
38:11So that's why these animals have created these acidic compounds that protect them.
38:16I can't imagine, you know, a world by which we can kind of reproduce a substance
38:22that hippos naturally manufacture and use it ourselves.
38:25That's something that we as human beings do, you know, with nature all the time.
38:31We find something that works really well on a creature,
38:33and then we try and kind of synthetically recreate it and use it for our own purposes.
38:37I think that if we came up with a moisturizing agent that was also a sunscreen
38:41and also an antibiotic or antimicrobial, what a win.
38:45While the hippo's chemical concoction protects it from the sun,
38:49another creature in the Arctic is busy producing something that prevents it from freezing in frigid waters.
38:55We know that fish, in a lot of cases, like to live in cold water.
38:59There's more oxygen. That's like a good environment for them to be in.
39:01Because of that, we forget that Arctic cod live in incredibly cold water
39:05that would freeze the tissues of a lot of other creatures.
39:09So cold is good until it gets to be too cold,
39:11and then you need some sort of mechanism to handle that.
39:14The presence of salt in seawater allows it to remain liquid until about negative 19 degrees Celsius.
39:21And the Arctic cod lives further north than any other fish,
39:26thriving in water well below the freezing point.
39:29These fish make their homes under ice and are found between 85 and 72 degrees north latitude
39:36in northern Russia, Greenland, Canada, and Alaska.
39:41The Arctic environment is probably one of the harshest environments.
39:44When you look at the animals that are up in the Arctic Ocean, they are covered in blubber.
39:48That's what keeps them warm, and that's what allows them to live up there and survive.
39:52Fish such as the Arctic cod have specific adaptations to live in a very cold environment.
39:57You have to be able to live where you don't freeze, and that's not an easy thing to do in
40:03the Arctic.
40:03The secret to this fish, being the ultimate sub-zero survivor,
40:07lies in its ability to manufacture a special chemical in its bloodstream,
40:13nature's own antifreeze.
40:15Where in temperatures drop below zero degrees Celsius, water is going to freeze.
40:19In everyday life, that's a problem mostly for vehicles because we have this radiator,
40:24and if we use water in the radiator of our vehicle, as soon as temperatures drop below freezing,
40:29the radiator would fail and we'd leak all our engine coolant temperatures.
40:32So we'll take glycol, which freezes at very, very low temperatures,
40:37and mix it with water so that we can have a fluid that doesn't freeze until minus 40 or colder.
40:42Similarly, the Arctic cod must keep its blood from freezing.
40:46It does so by producing a protein, consisting of one 309 molecule and two alanine molecules,
40:54hence its name, Thrallala.
40:57Thrallala is the perfect shape to stick to ice crystals and prevent them from growing.
41:02When ice first starts to grow, it nucleates a tiny crystal,
41:07and if you've ever seen the crystals grow on a frosty windshield of your car,
41:12well basically you've had one initiation site where the crystal first forms,
41:16and then the larger crystals grow off of that.
41:18If that happened in the cod, essentially its blood vessels would become plugged relatively quickly with these ice crystals.
41:25The protein that the cod produces actually binds to the surface of the first tiny water crystals that forms,
41:32and prevents those from growing.
41:34It basically changes the surface chemistry of the water crystals.
41:38As with so many other examples in the animal kingdom,
41:41the Arctic cod solution throws up possibilities for human use.
41:45We're looking to have compounds like what the cod have, again, to prevent nucleation and growth.
41:52And this will not only have engineering applications but medical applications
41:56where we can really cool organic things down without killing them.
42:02For example, when we get frostbite, what happens is our cells have a membrane around the outside of them,
42:08and that membrane is relatively fixed, it's not very stretchy.
42:11So when we expose our cells to really cold temperatures and it freezes,
42:16the cell needs to get 11% bigger to accommodate the formation of ice.
42:21But because the membrane isn't sufficiently flexible, we break the cell membrane and the cell dies.
42:27So the advantage of the cod is that these crystals never form and never continue to grow,
42:33and we never get that big volume change that results in the cells rupturing and dying.
42:39Using the cod's chemical to help humans in cold temperatures might just be around the corner.
42:44It has already been tested with GMO-bred mice, which experienced a 60% reduction in frostbite.
42:51If Thralala is being researched in the field of organ transplants,
42:55could this chemical be used to prevent damage in organs awaiting transplant?
43:00The protein has already been used successfully in one of our favourite cold treats.
43:06Ice cream is a really cool scientific study because there's a lot of things going on in ice cream.
43:13When we make ice cream, the first thing that we do is we cool it,
43:16but while we're cooling it, we stir it so that the fat is well distributed
43:19and we get this nice creamy flavour.
43:21In engineering of ice cream, we always want to try and keep those ice particles as small as possible.
43:27So having the cod's antifreeze protein in there would allow us to essentially have no ice crystals,
43:35and you'd essentially get this super creamy flavour coming through no matter what.
43:39Despite how we might use it, for the Arctic cod, this incredible chemical has been the key to its success.
43:46When we think about kind of all of the extreme places that exist on our planet,
43:52and you know, some of the most inhospitable places for human beings that we think of in the world
43:57have been colonised by various life forms.
43:59And in the case of kind of this cod, the environment that they are really highly adapted to
44:04are these incredibly cold waters.
44:06There are advantages for them, you know, living there.
44:09You may not have a lot of competition in those places.
44:12You can kind of get away from predators, and it may be just because you need kind of space to
44:16compete for,
44:17you know, for a species.
44:18And so it is with all the ways animals use biological chemistry.
44:23From Arctic cods, to African hippopotamuses, to glittering fireflies.
44:29Not only are they dazzling for us to discover, but they push us to evolve our own technologies and improvements.
44:35A lot of the ideas that we have, we think about, you know, creating substances and innovating.
44:40Most of the time we haven't innovated anything that nature hasn't already innovated better,
44:45earlier, in a more complete and a more sophisticated way.
44:48Nature has had all of the original ideas, and we've borrowed them,
44:51and just kind of played on them and riffed on them a little bit.
44:54Ultimately, there's no telling what new direction will be led in
44:58by one of the animal kingdom's master chemists.
45:20For the whole world, we have noticed that it's incredibly important and valuable science,
45:20and we've been interested in bringing food to the world within рук.
45:20We want people to get up with our own perspective
45:21and we've opened our hands on our heads,
45:21We've got ripe questions.
45:21We've got to eat and a little bit of food.
45:21We've got to eat and a little bit of food for a while.
45:23We've got to eat and a little bit of a way.
45:27We've got to eat and eat.
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