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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 cot 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.
00:56Whipped 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,
01:25and weighs up to 150 kilograms.
01:28But 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.
01:36Similar 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.
02:29What happens with a metabolism
02:30is it reflects the energy sources that 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
02:53till they have enough energy.
02:54The opportunity, you know, has come at the right time.
02:57It'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 their 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.
03:43When 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.
04:02Their 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 chainmail armor
04:10that surrounds them
04:11so 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.
04:28I mean, that's absolutely massive.
04:29The 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 that's necessary
04:45for 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 relaxes the cell walls of the prey,
05:30widening blood vessels and 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.
05:51There'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 downbite,
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,
06:07but 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
06:16will increase the bleed out,
06:18they'll act as anticoagulant
06:20so the wound 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
06:30in the animal kingdom.
06:32Having an advantage like Venom,
06:33where you can just strike and then sit back,
06:37wait 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
07:07was a mystery actually for 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
07:40never fall ill or 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.
07:58They'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
08:56for 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
09:31to 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
09:39that the scariest thing in the forest is the skunk
09:41and it's one of the few animals
09:43that will stand his ground
09:44and 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
09:54just 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,
10:02but it annoys us
10:03and puts us in discomfort
10:04to the point where we, like,
10:06have a visceral reaction
10:07to the sight of skunks in our communities.
10:10Skunks are a mammal only found in the Americas,
10:12and the most iconic of them,
10:14the striped skunk,
10:16lives in the U.S., Canada, and Mexico.
10:19Originally, they were classified under mustelids
10:21were otters, the weasels, martins.
10:24However, they have been reclassified
10:25to their own group, Mephididae.
10:27Skunks are omnivorous, eating plants and animals.
10:31Like raccoons, they are easily habituated
10:33to living near people,
10:35which has enabled them to thrive
10:37in 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
10:45to 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
10:54that they can get their hands on,
10:55from roots, berries, veggies, and meat.
10:58Among the animals that prey on them
11:00are domestic dogs, coyotes, bobcats, and owls.
11:04But even their predators tend not to prefer
11:06to go after skunks.
11:08Their defense is one of nature's
11:10most effective stink bombs.
11:13The skunk creates a noxious chemical
11:15in 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
11:22upon its target.
11:24The chemical itself is a combination
11:26of six thiols and one alkaloid.
11:30Thiols are a chemical of sulfur
11:32and hydrogen bonded together.
11:34There's a lot of thiols subtly
11:36in a lot of different organic things,
11:38and they're in onions and garlic
11:40in small amounts.
11:41This is what makes garlic smell,
11:43and onions cause our eyes to water.
11:47Thiols are particularly obnoxious compounds,
11:50and we actually use them in engineering
11:52quite frequently where we need an odorant.
11:55So in propane or natural gas,
11:57you may have noticed that it has a smell
11:59kind of like rotten eggs.
12:01Well, that's a thiol called mercaptan
12:03that we specifically add as an odorant,
12:06so that you can smell the natural gas
12:08of 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
12:17from natural gas and propane leaks.
12:19In skunk spray,
12:21three 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
12:35and lasts for a long time.
12:36When dogs get sprayed by skunks,
12:38you're usually advised
12:39to 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,
12:48it's suggested to use baking soda
12:50or hydrogen peroxide
12:52as 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,
13:04these chemicals are poisonous
13:05and can even kill predators.
13:08The skunk carries enough spray
13:10for 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 10 days to refill the gland.
13:21I like to picture the little scent gland
13:23of 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.
13:31What they actually do
13:32is they have nozzle-like protrusions
13:34where they can regulate the way that it is sprayed.
13:36So they can spray it in a mist,
13:38or they can even use a continuous stream,
13:40and they can shoot up to far distances
13:42with high accuracy.
13:43They have been recorded to do
13:45at a distance of over six meters.
13:47The ability to spray a liquid
13:49a relatively far distance
13:50is really dependent on the nozzle size
13:53and the volume of the container.
13:54So imagine taking a bulb
13:57with a really small hole in the end
13:59and filling the bulb full of liquid
14:00and then squeezing the bulb.
14:01You're going to be able to squirt the water out
14:03the small hole a long distance.
14:05Well, the skunk's essentially doing the same thing,
14:07is that they have a small orifice
14:09that releases the stinky liquid,
14:11and then they have a relatively large bladder
14:14with a muscle around it that squeezes it,
14:16giving them that six meter distance.
14:18There's not many creatures that can propel
14:22something out of their body that far.
14:24That six meters distance
14:25was 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
14:42and you only do have one defense,
14:44and it is your spray,
14:44you can't go around dispelling all of your spray,
14:48and then you are completely defenseless
14:50for up to two weeks as you build up more.
14:52Before using its spray,
14:53the creature has a few warning strategies.
14:56One of those is the stripe on its back,
14:59which is like an arrow
15:00that points to the source of its poison.
15:02We normally find that in nature
15:04when there are bright colorations
15:05or distinctive patterns.
15:07Those are normally advertising
15:09that 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
15:20to ward off a threat before spraying.
15:23They'll kind of stand on their front legs
15:24and do these kind of headstands.
15:26I find them really interesting
15:27because they don't, in fact,
15:29resemble any other threat display from an animal
15:32that could actually harm you.
15:33They are unique to skunks,
15:35and they're all to just kind of show off the fact,
15:36they're like, look, I'm a skunk.
15:38And it does work for them
15:39because we treat them with a lot of respect,
15:42a lot of distance,
15:43and in some cases, a little bit of fear.
15:46In fact, the skunk's chemistry
15:48has been mimicked by human defense systems
15:50to instill fear and distance.
15:53Created in the 2000s by the Israeli army,
15:57the skunk bomb is a synthetic crowd control measure
16:00modeled on actual skunk spray.
16:02It's designed to permeate victim clothing
16:04for up to five years.
16:06If 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,
16:13as 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,
16:22the noxious perfume it produces
16:24is enough to keep humans and animals away
16:26and ensure its success.
16:31While the skunk's chemistry is a repugnant repellant,
16:34an even smaller animal produces a far deadlier concoction
16:39while it lounges in the shallow waters
16:42of the Indian and West Pacific Oceans.
16:44Blue-ringed octopus, really incredible, tiny creature,
16:47small, really stunningly beautiful,
16:50really intricately patterned,
16:51and one of the most lethal animals
16:54on 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
17:00has enough venom to kill up to 26 humans.
17:04Fortunately for us,
17:05before we get too close to them,
17:07they flash the blue rings they are named after
17:09in order to warn us away.
17:12This incredible creature lives in tidal pools
17:15and coral reefs from 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, et cetera,
17:27are just this really unbelievable group of organisms.
17:31We know that they're quite intelligent.
17:32We know that they have problem-solving abilities.
17:35They were also masters of escape,
17:36and they can even, like, learn to communicate with us
17:39in some ways through the arsenal that they have available,
17:42through their color patterns.
17:43And what's really amazing is that most of them
17:45have incredibly short lives.
17:47So the fact that they're able to, you know,
17:50create this intelligence over, like, a lifespan
17:53that 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
18:15that can control how 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,
18:28called iridiphores.
18:30The iridiphores have this refractive quality
18:32that 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
18:42that when they contract, they 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
18:56to recognize you quickly and effectively
18:59that 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,
19:05they don't want to touch you.
19:07And in that case, that uniqueness means,
19:09I 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
19:28is 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.
19:55At first, the 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.
20:08However, 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.
20:19If you're a small creature that's evolved
20:21to have this, like, incredible 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.
20:39Luring 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 being able
20:52to 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,
21:02scientists and engineers are researching
21:05whether the blue-ringed octopuses' venom
21:06could be used strategically.
21:08When 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
21:17for some treatments for pain.
21:20Other medicinal uses could be in the treatment
21:22of allergies and cancer.
21:24Like the Komodo dragon's blood,
21:26the neurotoxins of cephalopods remain
21:28an untapped resource in drug discovery.
21:31There's another creature scientists look to
21:34for 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,
21:45the firefly triggers chemical reactions to create light.
21:49The light shows can be used to repel predators
21:52and attract mates,
21:54and they can also be weaponized to shocking effect.
21:57What fireflies do is they create this, like,
22:00beautiful 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,
22:29birds, mammals, and lizards.
22:31Firefly species have this defensive steroid molecule
22:35called lucifabagin
22:36that can be quite unappealing to a lot of predators
22:39like 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
22:57that, hey, I have this putrid odor
22:59that 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 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,
23:19you may regret it.
23:20We 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
23:29and some bird wants to eat you,
23:31and you take this position where all of a sudden
23:34your rear end comes up a bit like scorpion-like,
23:37and at the same time it glows.
23:38Quite impressive.
23:40Probably deters something initially enough for it
23:42to give it a split second to maybe scamper away.
23:45How exactly does the firefly make its warning light?
23:49Bioluminescence is really quite cool.
23:51I mean, it's surprisingly prolific
23:54throughout the animal kingdom.
23:55It shows up in many different sea creatures,
23:58in not just simple life forms,
24:01but in complex life forms like fish and octopus.
24:04As laypeople, we don't see light
24:06as a byproduct of chemical reactions.
24:10It is.
24:11It's just not that common,
24:12and it's not in our everyday occurrence
24:14until we see it.
24:16Chemical reactions all release energy.
24:18Most of the time we think of those chemical reactions
24:21producing heat as a byproduct.
24:23When we stick two things together,
24:25we get foaming and we get boiling.
24:27But a lot of chemical reactions are much more subtle,
24:30producing new compounds,
24:31and in some cases producing light.
24:33When you think of light, you think of heat.
24:36But if that were the case with fireflies,
24:37they would simply overheat and die.
24:39So that's why the reaction of light
24:41is actually through chemical compounds
24:42that they have in certain organs of their body.
24:44They emit light through their clear abdomen
24:47that allows them to show the reaction
24:50that is going inside their body.
24:51The light that is produced in their light organ
24:54is the result of a chemical reaction
24:56at the cellular level between luciferin and oxygen,
25:00catalyzed by luciferase.
25:03When luciferase, calcium, adenosine, and triphosphate,
25:07also called ATP, come into contact with oxygen,
25:10it oxidizes and creates a new molecule
25:13that is highly unstable.
25:15The molecule quickly breaks down,
25:17releasing light energy as it does.
25:19Luciferin is an organic compound.
25:21ATP is the energy source in the cells,
25:25and oxygen is always in biology there to extract energy.
25:29We're always oxidizing our fuel energy.
25:32The last component is an enzyme,
25:34and enzymes are really neat compounds in biology
25:36in that they don't actually participate in the reaction,
25:40they just help it happen.
25:42So without the enzyme,
25:45the reaction goes very, very, very slowly,
25:47and you would get a little bit of light.
25:49But when you provide the enzyme,
25:52the 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
25:58because it's not just a single compound
26:01that the firefly is producing,
26:03it's a compound, an enzyme,
26:06the energy storage, and still the oxygen
26:08that is breathing from its environment
26:09all have to come together and have a relatively rapid reaction
26:13to get this volume or this intensity of light
26:17produced from the firefly.
26:18As if chemically causing oneself to glow is not enough,
26:23fireflies take bioluminescence to a whole new level.
26:26These animals not only emit light,
26:28but 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.
26:37So one species may produce a signal that is a flash of light,
26:43just one at a time.
26:44Just flash, flash, flash.
26:47And then there are others that might go
26:49two short flashes and a long flash.
26:52While they first evolved bioluminescence
26:55as a warning light to predators,
26:57this amazing bug then adapted the capability
26:59to flash its light in 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
27:18than the other species around you
27:20because you don't want to mate
27:21with the other species because the offspring,
27:25if they survive, are usually inferior.
27:28And given that the firefly only reaches sexual maturity
27:31in the last two weeks of its two-month lifespan,
27:35its ability to flash in code
27:36is an extremely fortunate design tweak.
27:39It needs all the help it can get.
27:41Game on.
27:42As 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,
27:48and that's what they're doing.
27:50I have two weeks, and I have to do this thing
27:52that 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,
28:00or the beginning and ending of each chemical reaction,
28:03the firefly does two things.
28:05First, it can control the muscle
28:08that transports the oxygen to the light organ.
28:10Secondly, it again puts its chemist hat back on
28:14and has the light organ produce nitric oxide,
28:16which intensifies the chemical,
28:18and therefore light energy process.
28:21Chemical reactions are difficult to control
28:24at the best of the times,
28:25and we have entire specializations in chemistry and engineering,
28:30trying to make sure reactions happen
28:32in a really tight framework so that it doesn't go too fast
28:35and doesn't take too much energy and doesn't go too slow.
28:38But somehow the firefly has this built-in mechanism
28:42that allows it to very carefully control
28:44that reaction chemistry and control it consistently
28:48to do 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
28:58and attract mates, one species, dubbed the femme fatale,
29:03uses it as a truly dark art.
29:06A guy called Jim Lloyd first discovered it,
29:08and basically what happens is that a female,
29:12when 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
29:23and was going beep, 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,
29:33and then she actually eats them.
29:35It's like delivering a pizza, you know,
29:37I don't go out and look for it, I'll bring it to me.
29:40They actually can harvest the defensive steroids
29:43found in those animals and use it to their own advantage
29:45and pass it on to their offspring.
29:48Ultimately, being even more toxic
29:50due to the increase in leucibiofagins,
29:52the femme fatale has a much better chance of being spit out
29:55if she finds herself in the mouth of a predator.
29:58And whether for safety, sex, or cannibalism,
30:02bioluminescence in the firefly
30:03has taken at least 100 million years to evolve.
30:06It's not surprising that scientists have wondered
30:09about human applications.
30:10What the firefly is doing is essentially
30:14exactly 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
30:24using a chemical means.
30:26But really, really similar in terms of
30:28what's happening at the atomic scale.
30:30While harvesting fireflies for free light is impractical,
30:34the fireflies' luciferin chemistry
30:36has inspired a new method of whole body imaging.
30:40Recently, a gene that encodes firefly luciferase
30:43was 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
30:50so that we can tag certain genes and know where they are.
30:54And that's the crazy thing about biology to me
30:56is that every single physical phenomena we find
31:00as 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
31:13is in the riverbeds of Africa.
31:16Only recently discovered,
31:18scientists are taking a closer look
31:20at what appears to be nature's most advanced skin cream.
31:23Although the task is much easier said than done,
31:27Hippos are considered one of the most dangerous animals
31:30on our planet
31:31and have very little threats
31:34that they are going to be facing.
31:36Perhaps a brave crocodile might go after a young hippo,
31:40but it is a lot of risk to take on this feat.
31:43We think of them as, like, lumbering, slow,
31:46kind 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 meters high,
31:58or nine and a half to 14 feet,
32:00and they weigh 1,300 to 3,600 kilograms.
32:04I mean, when you're a hippo and you weigh, you know, a ton,
32:08and you're huge, you have a lot of kind of physical power
32:11to kind of back up your aggression.
32:13Extremely territorial,
32:15they not only fight off other species,
32:17but frequently other hippos that enter their territory.
32:20I was on safari, we were on the boat,
32:22and I heard my wife beside me scream,
32:25and out of the bushes beside the boat
32:26charged a hippo with his mouth wide open
32:29and bumped the boat.
32:30But the hippo bumped and backed down,
32:32and we were all okay.
32:33I got a good look at the hippo,
32:35and one of the things I noted was that
32:36he'd obviously been in a major fight.
32:39They're often very heavily scarred,
32:40and they have huge scars all over their body from their fights.
32:43When you do see videos of hippo fight scenes
32:46where you have the males with their mouths open,
32:49you know, almost 180 degrees wide open
32:52with these huge tusks battling each other,
32:55and those tusks often gore each other
32:57and cause large wounds on the skin of the hippopotamus.
33:00Still, there is another danger
33:02the 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
33:10with hippos have, you know, adapted to the fact
33:13that the sun is so bright and powerful in those areas
33:15by kind of living in environments where that's blocked out,
33:18by living kind of under forest canopies.
33:20But hippos live in exposed pieces of river
33:23where there aren't trees covering them,
33:26and they are more exposed than a lot of other creatures.
33:30Although hippos are semi-aquatic
33:32and spend most of their life submerged in water,
33:34they prefer to stay on their feet.
33:37Hippos were fondly nicknamed river horses
33:39by the Greek when they first encountered these species,
33:42and they actually cannot swim very well
33:45because of their very dense body shape.
33:48They actually just kind of push themselves
33:50from the bottom in shallow areas
33:52and almost look like underwater ballerinas.
33:55And they might spend the entire day
33:57lounging in the sunny riverbanks,
33:59for this herbivore typically grazes in the evening
34:02when it's cooler.
34:04The sun is a driving force of life on our planet,
34:07but also has destructive properties,
34:09especially the radiation that it brings into our atmosphere.
34:12One of the things about solar radiation
34:14is it comes in different wavelengths.
34:16What we see is the visual spectrum,
34:19so red, green, blue, orange, yellow, etc.
34:22But beyond the visible spectrum at the higher energy levels
34:25is UV light, ultraviolet light.
34:28And ultraviolet light behaves with biological systems
34:30a little bit different than visual light.
34:32The energy in the photons of the ultraviolet light
34:35is so high that it can start to break down the proteins
34:38in our body and break down the compounds and cause damage.
34:41And in fact, the UV light can actually break down DNA
34:44and lead to mutations and cancer, etc.
34:47So that UV spectrum in the light coming from the sun
34:50can actually be quite dangerous,
34:52especially an animal in the Serengeti.
34:54They have very long dry seasons,
34:57very low moisture in the air.
34:58If you're not heavily furred, you need to have some mechanism
35:02to protect you from the sunshine.
35:04As humans, we have certain adaptations,
35:07although it is quite limited.
35:08We can produce a melanin in our skin,
35:10which is a pigment that allows the scattering
35:12of these UV radiation
35:14and prevents the absorption into our skin.
35:17However, some animals have developed ways
35:19that 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.
35:27Or can they?
35:29The answer might be yes.
35:31Nature has come up with this amazing solution
35:34to a lot of the problems that hippos face
35:36just by being in the beating sun for so long.
35:39Their pores and their skin secrete this red substance,
35:43which actually acts as a sunscreen,
35:46which blocks the UV rays of the sun and protects them.
35:50When the hippo emerges out of the water,
35:52they appear to sweat a rust-colored pigment.
35:55It's not true sweat,
35:57because the hippo does not actually have sweat glands.
36:00But it has other glands just under the skin
36:02that produce this special thick oily substance,
36:05which it then releases through the skin.
36:08It consists of two acids and a mucus,
36:11or hipposudoric acid, is orangish in color,
36:14and acts as a sunscreen.
36:16The red compound that the hippos release
36:19is 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.
36:29So those will usually be a zinc oxide material that is inorganic,
36:34so it's basically a powdered, almost like a paint material.
36:38And the other one is to use organic compounds,
36:41which specifically absorb UV light in specific spectrums.
36:44The hippopotamus's UV protection
36:47that it secretes from glands on its body is the latter.
36:50The second acid, hipposudoric,
36:52is red in color and acts as an antibiotic.
36:55Not only do they get this great secretion
36:58that protects them from sunshine,
36:59because they're such prolific fighters
37:01and get a large number of wounds,
37:04that same compound also protects them against infections,
37:08when they are injured.
37:09Lastly, the mucus helps to keep the skin moist
37:12when they emerge from the water,
37:13which is good,
37:14because 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
37:22that, you know, acts as a sunscreen,
37:24acts as an antibiotic,
37:26and also acts as a moisturizer.
37:27They're all like a beauty boutique, all-in-one.
37:30It doesn't come as a surprise
37:31that some of the chemical companies
37:33interested in the hippo's special source
37:35are skin care manufacturers.
37:37If they could crack this code for human skin,
37:40it could be priceless.
37:42Yet, ironically, this compound
37:45that evolutionists perfected over eons for the hippo
37:48would be of no value to its closest relative.
37:51Hippos are actually the closest relatives
37:53to 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
38:08to protect themselves from being under the sun.
38:11So that's why these animals have created these acidic compounds
38:15that protect them.
38:16I can't imagine, you know, a world by which we can kind of reproduce
38:21a substance that hippos naturally manufacture and use it ourselves.
38:25That's something that we as human beings do, you know,
38:28with nature all the time.
38:30We find something that works really well on a creature,
38:33and then we try and kind of synthetically recreate it
38:36and use it for our own purposes.
38:37I think that if we came up with a moisturizing agent
38:40that was also a sunscreen and also an antibiotic
38:42or 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
38:52that 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.
39:00That'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
39:18until 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
39:32and 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,
39:47they are covered in blubber.
39:48That's what keeps them warm,
39:49and that's what allows them to live up there and survive.
39:52Fish, such as the Arctic cod,
39:54have specific adaptations to live in a very cold environment.
39:57You have to be able to live where you don't freeze,
40:01and that's not an easy thing to do in the Arctic.
40:04The 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,
40:18water is going to freeze.
40:19In everyday life, that's a problem mostly for vehicles
40:22because we have this radiator,
40:24and if we use water in the radiator of our vehicle,
40:27as soon as temperatures drop below freezing,
40:29the radiator would fail and we'd leak all our engine coolant tankers.
40:32So we'll take glycol, which freezes at very, very low temperatures,
40:36and mix it with water so that we can have a fluid
40:40that 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,
40:49consisting of one 309 molecule and two alanine molecules,
40:54hence its name, Thralala.
40:57Thralala is the perfect shape to stick to ice crystals
41:00and prevent them from growing.
41:02When ice first starts to grow,
41:05it nucleates a tiny crystal,
41:07and if you've ever seen the crystals grow
41:10on a frosty windshield of your car,
41:11well, basically you've had one initiation site
41:14where the crystal first forms,
41:15and then the larger crystals grow off of that.
41:18If that happened in the cod,
41:20essentially its blood vessels would become
41:22plugged relatively quickly with these ice crystals.
41:25The protein that the cod produces
41:27actually binds to the surface
41:29of the first tiny water crystals that form
41:32and prevents those from growing.
41:34It basically changes the surface chemistry
41:36of the water crystals.
41:37As with so many other examples in the animal kingdom,
41:41the Arctic cod solution
41:43throws up possibilities for human use.
41:46We're looking to have compounds like what the cod have,
41:50again, to prevent nucleation and growth,
41:52and this will not only have engineering applications
41:55but medical applications
41:56where we can really cool organic things down
42:00without killing them.
42:02For example, when we get frostbite,
42:04what happens is our cells have a membrane
42:07around the outside of them,
42:08and that membrane is relatively fixed.
42:10It's not very stretchy.
42:11So when we expose our cells to really cold temperatures
42:15and it freezes, the cell needs to get 11% bigger
42:19to accommodate the formation of ice.
42:21But because the membrane isn't sufficiently flexible,
42:25we break the cell membrane and the cell dies.
42:27So the advantage of the cod is that these crystals never form
42:31and never continue to grow
42:33and we never get that big volume change
42:35that results in the cells rupturing and dying.
42:38Using the cod's chemical to help humans in cold temperatures
42:41might just be around the corner.
42:44It has already been tested with GMO-bred mice,
42:47which 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
42:58in organs awaiting transplant?
43:00The protein has already been used successfully
43:03in one of our favourite cold treats.
43:06Ice cream is a really cool scientific study
43:10because 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
43:17so 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
43:24and keep those ice particles as small as possible.
43:27So having the cod's antifreeze protein in there
43:31would allow us to essentially have no ice crystals
43:35and you'd essentially get the super creamy flavour coming through
43:38no matter what.
43:39Despite how we might use it,
43:41for the Arctic cod, this incredible chemical
43:44has been the key to its success.
43:47When we think about kind of all of the extreme places
43:50that exist on our planet,
43:52and, you know, some of the most inhospitable places
43:55for 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,
44:01the 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
44:13and it may be just because you need kind of space
44:16to compete for, you know, for a species.
44:18And so it is with all the ways
44:21animals use biological chemistry.
44:23From Arctic cods, to African hippopotamuses,
44:26to glittering fireflies.
44:28Not only are they dazzling for us to discover,
44:31but they push us to evolve our own technologies
44:34and improvements.
44:36A lot of the ideas that we have,
44:37we think about, you know, creating substances
44:39and innovating.
44:40Most of the time we haven't innovated anything
44:43that nature hasn't already innovated
44:45better, earlier, in a more complete
44:47and a more sophisticated way.
44:48Nature has had all of the original ideas
44:50and we've borrowed them
44:51and just kind of played on them
44:53and riffed on them a little bit.
44:54Ultimately, there's no telling
44:56what new direction will be led in
44:57by one of the animal kingdom's master chemists.
45:01as we look at this,
45:30we take the time away.
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