0:00:02 > 0:00:05This is Deadly 360,
0:00:05 > 0:00:09the show that pits three of the world's deadliest predators
0:00:09 > 0:00:10against their prey.
0:00:10 > 0:00:18Examining their hunting strategies and escape tactics from every angle.
0:00:18 > 0:00:21We find out why a hunt succeeds.
0:00:23 > 0:00:26And why they sometimes fail.
0:00:26 > 0:00:31One thing's certain - prey animals are anything but sitting ducks.
0:00:31 > 0:00:36Their defensive strategies keep them alive.
0:00:36 > 0:00:40And push predators to the limits.
0:00:40 > 0:00:44Prepare for Deadly 360.
0:00:44 > 0:00:50This is Deadly 360 mission control, where all of today's action
0:00:50 > 0:00:53and analysis takes place.
0:00:53 > 0:00:59We have access to some of the most enthralling hunts caught on camera.
0:00:59 > 0:01:01I've recreated three of
0:01:01 > 0:01:06the most exciting and analysed them in true 360-degree style.
0:01:08 > 0:01:12The predators have to find food or they won't make it.
0:01:12 > 0:01:17In the wild world, surviving is the greatest challenge.
0:01:17 > 0:01:20I present to you the cephalopods.
0:01:20 > 0:01:23Octopus, cuttlefish and squid.
0:01:23 > 0:01:27Probably the most intelligent invertebrates.
0:01:27 > 0:01:31We'll witness a squid assault,
0:01:31 > 0:01:35find out why this cuttlefish is a master of disguise,
0:01:35 > 0:01:40and uncover the hidden horror under an octopus's arms.
0:01:40 > 0:01:44They look invincible but there's a continual arms race
0:01:44 > 0:01:47in nature, ensuring that prey animals
0:01:47 > 0:01:51evolve spectacular ways of taking care of themselves.
0:01:51 > 0:01:57Today's defenders include an armour- clad warrior of the deep - the crab.
0:01:57 > 0:02:01A shrimp with a cloak of invisibility.
0:02:01 > 0:02:05And an army of fish that use numbers to outwit the enemy.
0:02:05 > 0:02:11Three different prey. How will they fare against our predators?
0:02:11 > 0:02:14I've introduced you to our contenders.
0:02:14 > 0:02:19It's time to meet our first deadly duo going head to head.
0:02:19 > 0:02:25For the predators, the most well-known cephalopod, the octopus.
0:02:25 > 0:02:28A hunter with clever adaptations.
0:02:28 > 0:02:30Up against it is this.
0:02:30 > 0:02:35A crab, loaded with heavy duty weaponry and clad in armour.
0:02:35 > 0:02:39But which animal has the edge in the race for life?
0:02:39 > 0:02:41It's time to go Deadly 360.
0:02:45 > 0:02:48We look at a critical moment.
0:02:48 > 0:02:51We're in shallow waters offshore.
0:02:51 > 0:02:56A crab has strayed and there's an octopus closing in.
0:02:56 > 0:03:01There's no escape for the crab. It's going to have to fight.
0:03:01 > 0:03:05But will those claws be any good against a hungry octopus?
0:03:05 > 0:03:09It looks like the prey is in serious trouble.
0:03:09 > 0:03:13But how did it get there and is there any chance it might survive?
0:03:13 > 0:03:17To answer these questions, we'll wind back to
0:03:17 > 0:03:22the start of the hunt and find out what leads up to this strike.
0:03:24 > 0:03:26Where are we?
0:03:26 > 0:03:28This hunt is taking place
0:03:28 > 0:03:32around the UK, just off the south coast here.
0:03:32 > 0:03:36It's summer so the sea temperature's high,
0:03:36 > 0:03:40which suits our octopus, who prefers temperate waters.
0:03:40 > 0:03:46Rocks and seaweed provide cover, good for both hunting and hiding.
0:03:48 > 0:03:50So that's our location.
0:03:50 > 0:03:54What attributes do our predator and prey have
0:03:54 > 0:03:57that will give them an advantage?
0:03:57 > 0:04:02First up, the octopus. It's a complex predator.
0:04:02 > 0:04:05It has eight arms for grasping its prey
0:04:05 > 0:04:10and a beak with venomous saliva, plus other surprising abilities.
0:04:10 > 0:04:13More on those later.
0:04:13 > 0:04:19So that's our predator. Time to find out about its prey's defences.
0:04:19 > 0:04:24The crab's most obvious way of fending off an attack
0:04:24 > 0:04:29is with its two pincers, which exert a powerful crushing force.
0:04:29 > 0:04:34Add to that an armoured shell, and it's anything but an easy meal.
0:04:34 > 0:04:38Based on that, this will be an interesting hunt.
0:04:38 > 0:04:44Let's see how it unfolds. We're back at the start of the day.
0:04:44 > 0:04:48Our predator is in its den, tucked away among the rocks.
0:04:48 > 0:04:52An octopus has no bones at all in its body, which means it can
0:04:52 > 0:04:56slip that soft, rubbery form into the tiniest of gaps.
0:04:56 > 0:05:01A useful adaptation, but a soft body is vulnerable to attack.
0:05:01 > 0:05:07It needs to be careful, particularly if it hunts for one of these.
0:05:07 > 0:05:11The crab is armed with those brutal pincers.
0:05:11 > 0:05:15A more effective defence for the crab is to hide.
0:05:15 > 0:05:19Its colouring makes it hard to pick out.
0:05:19 > 0:05:22As long as the octopus can't see it, it's safe.
0:05:22 > 0:05:26It looks like another crab is approaching.
0:05:28 > 0:05:34Crabs are territorial. They'll fight rivals who muscle in on their patch.
0:05:34 > 0:05:39You can look at this crab's pincers. They have a serrated edge.
0:05:39 > 0:05:42They can break into a mussel's shell.
0:05:42 > 0:05:46It's not uncommon for a crab to have a pincer
0:05:46 > 0:05:51or a leg snapped off in one of these squabbles.
0:05:51 > 0:05:55The invaders back down but the fight has distracted
0:05:55 > 0:06:00the first crab and allowed the octopus to sneak up.
0:06:02 > 0:06:07It has to hold its prey whilst avoiding those claws.
0:06:07 > 0:06:11How will it do that? Let's take a closer look at this predator.
0:06:13 > 0:06:18An octopus's eight arms are remarkable tools.
0:06:18 > 0:06:21The octopus has no internal skeleton
0:06:21 > 0:06:25but because the muscles are packed so tightly
0:06:25 > 0:06:29it has an extraordinary amount of strength.
0:06:29 > 0:06:35Because it doesn't have hard bones, it can twist those arms.
0:06:35 > 0:06:38It has unrestrained flexibility.
0:06:38 > 0:06:43On the underside of each one of those arms are suction cups.
0:06:43 > 0:06:46They're muscular and possess taste buds.
0:06:46 > 0:06:51It's almost as if it is covered in tiny tongues,
0:06:51 > 0:06:56that it can place into any crack to find out what's inside.
0:06:56 > 0:07:00It may seem that it is a soft animal
0:07:00 > 0:07:06but it's presenting a master class in sensitivity and strength.
0:07:08 > 0:07:11Now that the crab's been spotted,
0:07:11 > 0:07:15hiding under a rock will be little defence
0:07:15 > 0:07:19against the octopus's arms, which could grab it.
0:07:19 > 0:07:23The crab's next instinct is to make a run for it.
0:07:26 > 0:07:33An octopus's locomotion is slow but it has one method of speed.
0:07:33 > 0:07:38It drives water out of its body through the siphon,
0:07:38 > 0:07:42which can make it go up to 25 miles an hour.
0:07:42 > 0:07:46That's more than enough to catch up with the crab.
0:07:46 > 0:07:50If the prey can't run, its only option is to fight.
0:07:50 > 0:07:56The octopus needs to be careful - those pincers could do some damage.
0:07:56 > 0:07:59That's worth another look.
0:07:59 > 0:08:06The octopus moves with great speed and envelops the crab in its arms.
0:08:06 > 0:08:10The crab simply has no chance to use those pincers.
0:08:10 > 0:08:15Is that hunt over? Maybe not. The crab has a last line of defence.
0:08:15 > 0:08:21This is an edible crab. It is alive, although it's quite compacted,
0:08:21 > 0:08:26drawing all its limbs in to protect itself.
0:08:26 > 0:08:34It's got this pie-crust shape and a pinky or orange colour.
0:08:34 > 0:08:39The first thing you notice is the pincers. They are massive.
0:08:39 > 0:08:45There are fishermen missing fingers due to claws like these.
0:08:45 > 0:08:47Once a crab has been enveloped,
0:08:47 > 0:08:51those pincers will be of limited use.
0:08:51 > 0:08:56The octopus wants to get to the soft body parts inside this shell,
0:08:56 > 0:09:01and that armour is now the crab's last line of defence.
0:09:01 > 0:09:05It's got two constituents. The first is a protein called chitin
0:09:05 > 0:09:10which can be rubbery, and the other is calcium carbonate.
0:09:10 > 0:09:13It is hard but has a tendency to be brittle.
0:09:13 > 0:09:20This shell could be cracked and then the crab is going to be helpless.
0:09:20 > 0:09:25Let's see if our octopus can breach these defences.
0:09:25 > 0:09:28The hunt is a race against time.
0:09:28 > 0:09:31Every minute the octopus maintains that grasp
0:09:31 > 0:09:36on the crab, it's also vulnerable to attack.
0:09:36 > 0:09:40The first thing it'll do is carry the crab to its den.
0:09:40 > 0:09:44This should give it more time to crack through that body armour.
0:09:44 > 0:09:49This needs to be done with precision to prevent the crab
0:09:49 > 0:09:52launching a counter-attack.
0:09:52 > 0:09:58The octopus has some tools underneath all of those arms.
0:09:58 > 0:10:00To find out how this works,
0:10:00 > 0:10:05we'll head to the business end of the octopus, the mouth.
0:10:05 > 0:10:10Inside there are two structures. One is the radula,
0:10:10 > 0:10:14which can wear away the crab's shell.
0:10:14 > 0:10:17The other is covered in papilla.
0:10:17 > 0:10:22These can be used to drill a hole into the crab's soft body.
0:10:22 > 0:10:26Next, the octopus will inject a venom into the crab.
0:10:26 > 0:10:29It might look like nothing's happening,
0:10:29 > 0:10:33but the prey is being torn apart.
0:10:33 > 0:10:38It's taken the octopus about 20 minutes, but it's broken through
0:10:38 > 0:10:40the crab's defence and now it
0:10:40 > 0:10:45devours the flesh inside.
0:10:45 > 0:10:50The octopus might appear to be a soft-bodied sort,
0:10:50 > 0:10:54but there's nothing soft about this predator.
0:10:54 > 0:10:58Imagine something drilling a hole in your head
0:10:58 > 0:11:01and injecting a toxin that destroys you.
0:11:01 > 0:11:04Not a nice way to go.
0:11:04 > 0:11:11The crab had decent vision. Pincers. And that tough outer shell.
0:11:11 > 0:11:15The octopus was equipped with sucker-lined arms,
0:11:15 > 0:11:18its radula and that lethal toxic venom.
0:11:18 > 0:11:21The crab may have been well protected but this time,
0:11:21 > 0:11:27the octopus's surgical skills were enough to break in and get its meal.
0:11:30 > 0:11:35Now on to our next pair of hunters locked in a battle for survival.
0:11:35 > 0:11:39For the predators, we have a monster of the deep.
0:11:39 > 0:11:42It's the Humboldt Squid.
0:11:42 > 0:11:47And up against it is this. A massive shoal of open water fish,
0:11:47 > 0:11:51each one a swimmer with evasion techniques.
0:11:51 > 0:11:55But which has the edge in the race for life?
0:11:55 > 0:11:57It's time to go Deadly 360.
0:12:02 > 0:12:06We've dropped right into a deep sea battle. It's mayhem!
0:12:06 > 0:12:10There are fish and squid rocketing around like heat-seeking missiles.
0:12:10 > 0:12:15It's almost impossible to figure out what's going on.
0:12:15 > 0:12:21We need to wind back the hunt. It'll make sense of what we've seen.
0:12:21 > 0:12:24Let's start with the location.
0:12:24 > 0:12:27We're off the coast of Mexico.
0:12:27 > 0:12:32We're 30 metres down so there's not much to see
0:12:32 > 0:12:37but there is a seabed below. Will that be a factor in this hunt?
0:12:39 > 0:12:43That's the arena for our gladiatorial contest.
0:12:43 > 0:12:47What weapons and defences do the two animals doing battle have?
0:12:47 > 0:12:52First the Humboldt squid. It grows up to two metres long.
0:12:52 > 0:12:56It's fast and has nasty arms.
0:12:58 > 0:13:02All of that makes our predator a scary prospect.
0:13:02 > 0:13:07What does our prey have? Their main defence is to shoal,
0:13:07 > 0:13:13using strength in numbers to increase their survival chances.
0:13:13 > 0:13:16They also have a detection system.
0:13:16 > 0:13:20It won't be easy for any predator to pick off that prey.
0:13:20 > 0:13:23That's the background, let's get the hunt under way.
0:13:23 > 0:13:28We're at the start of the action and it's the fish that are hunting.
0:13:28 > 0:13:34They work together to feed on tiny crustaceans called krill.
0:13:34 > 0:13:37But they could soon be the ones in the firing line,
0:13:37 > 0:13:41cos there's a Humboldt squid in the area,
0:13:41 > 0:13:43and from the shapes in the background
0:13:43 > 0:13:45it looks like it's not alone.
0:13:45 > 0:13:50Hundreds of squid head towards the fish, also operating as a group!
0:13:50 > 0:13:53Humboldts are highly intelligent.
0:13:53 > 0:13:57They hunt together in vast packs, sometimes over 250 squid strong.
0:13:57 > 0:14:02And each one is equipped with a whole lot of arms.
0:14:02 > 0:14:05Oh! That's definitely worth another look!
0:14:05 > 0:14:08As the squid splays open those eight arms,
0:14:08 > 0:14:12there are also two hidden tentacles that we can't see here.
0:14:12 > 0:14:15What we can see are those suction cups.
0:14:15 > 0:14:18Each one is lined with a row of unbelievably sharp teeth.
0:14:18 > 0:14:23When they latch on there's almost no chance its victim will escape.
0:14:23 > 0:14:26They'll drag it back towards the mouth
0:14:26 > 0:14:29where the real horror show starts.
0:14:29 > 0:14:35The bodies of octopus and squid are soft, apart from the tiny teeth that
0:14:35 > 0:14:40line the sucker cups on their arms and tentacles, and this monstrosity.
0:14:40 > 0:14:43This is the beak of a deep-water squid
0:14:43 > 0:14:46and it really is a fearsome tool.
0:14:46 > 0:14:50It's made of chitin, often found in the natural world.
0:14:50 > 0:14:55It's soft and pliable towards the end where it binds to the muscles
0:14:55 > 0:15:00and rock-hard and very, very pointy at the end of the beak here.
0:15:00 > 0:15:03This section kind of looks like a parrot's beak,
0:15:03 > 0:15:06but actually in function, it is quite different.
0:15:06 > 0:15:10They use it to bite clean through the spinal cords of fish,
0:15:10 > 0:15:12which paralyses them instantly,
0:15:12 > 0:15:17and then to chomp them apart and feed them back here into the mouth.
0:15:17 > 0:15:20It's interesting that it can generate so much force
0:15:20 > 0:15:24and it's powered by muscles that look like jelly.
0:15:24 > 0:15:28But cos they've got a circular strap-like formation like this,
0:15:28 > 0:15:32they can generate enormous force by just clenching
0:15:32 > 0:15:35and that drives the beak closed
0:15:35 > 0:15:37and takes a really sizable bite.
0:15:37 > 0:15:40As I found out when I found one of these in the wild
0:15:40 > 0:15:41and got bitten!
0:15:41 > 0:15:43Have a look at this.
0:15:45 > 0:15:47It's got its tentacles around my arm
0:15:47 > 0:15:51and I can feel the gripping of those teeth.
0:15:51 > 0:15:55Actually, you can feel it even through the chainmail suit.
0:15:55 > 0:16:02And in here, that's where that snapping beak is - just there.
0:16:02 > 0:16:07I'm going to take great care not to get my fingers close to it,
0:16:07 > 0:16:09cos I think I'd lose them.
0:16:09 > 0:16:13It's actually... Arrrrgh! Dear me! This is...
0:16:13 > 0:16:16Arrrrgh! The strength of the beak!
0:16:16 > 0:16:22It just actually bit me right through the chainmail suit.
0:16:22 > 0:16:25Actually, I got off quite lightly there!
0:16:25 > 0:16:27They have been known to break bones,
0:16:27 > 0:16:29even through the chainmail suit!
0:16:29 > 0:16:34So what chance does the fish have? Let's see.
0:16:34 > 0:16:38The Humboldt hunting party is closing in fast on its prey.
0:16:38 > 0:16:42Like octopus, these squid have siphons to jet-propel themselves
0:16:42 > 0:16:46through the water either forwards or backwards.
0:16:46 > 0:16:50The fish's response to the threat is to stick together.
0:16:50 > 0:16:53Moving in a vast pulsating shoal makes it much harder
0:16:53 > 0:16:56for the squid to pick out a single target,
0:16:56 > 0:16:58and helps to minimise casualties.
0:16:58 > 0:17:02But remember, the squid are also working as a team,
0:17:02 > 0:17:05trying to drive the fish up against the rocks
0:17:05 > 0:17:10in order to split up the shoal and give themselves the advantage.
0:17:10 > 0:17:14It looks like an all-out assault is about to begin.
0:17:14 > 0:17:18But once the carnage starts, what other mechanisms do the fish
0:17:18 > 0:17:20have to avoid being hooked?
0:17:20 > 0:17:25It might seem that the life of a small fish is pretty rubbish.
0:17:25 > 0:17:29I mean, it kind of seems like their only purpose is to get eaten.
0:17:29 > 0:17:32But it doesn't mean they're defenceless.
0:17:32 > 0:17:36They do have one sense that allows them to see the world around them
0:17:36 > 0:17:38in a completely different way to us.
0:17:38 > 0:17:42Running down the length of their body is a lateral line.
0:17:42 > 0:17:46In some species of fish it's clearly visible,
0:17:46 > 0:17:49but if you look at it under a very high powered microscope,
0:17:49 > 0:17:54what you see are tiny hairs, capable of discerning movement in the water.
0:17:54 > 0:17:58As a predator swims through the water, it creates a wake,
0:17:58 > 0:18:03very much like a boat does, and the fish can sense it coming.
0:18:03 > 0:18:06The second it feels a threat nearby
0:18:06 > 0:18:08the fish can make a dart for safety.
0:18:08 > 0:18:12Let's see if the squid is going to have any chance of catching
0:18:12 > 0:18:14these slippery subjects.
0:18:17 > 0:18:21The first squid moves in and the full-out assault begins.
0:18:21 > 0:18:26The prey's defences are being tested to the limit.
0:18:26 > 0:18:31The fish may be fast but squid are also attacking at phenomenal speed.
0:18:31 > 0:18:33If we slow the action down,
0:18:33 > 0:18:36their strikes are almost too fast for us to see.
0:18:36 > 0:18:39They strike using those arms and tentacles,
0:18:39 > 0:18:43grab the fish and drag it back towards their beak.
0:18:43 > 0:18:46It's all over in about 20 milliseconds.
0:18:48 > 0:18:52Even with their lateral line and a body built for high-speed evasion,
0:18:52 > 0:18:56it's difficult for the fish to cope with such a strike.
0:18:56 > 0:18:59But, it looks like the attack is coming to an end.
0:18:59 > 0:19:03Either they have eaten enough or they've run out of puff.
0:19:03 > 0:19:07Incredibly, despite the attack from hundreds of hungry squid,
0:19:07 > 0:19:10it appears that many of the fish have survived.
0:19:10 > 0:19:14A smaller shoal might've been wiped out,
0:19:14 > 0:19:17but the sheer numbers working together in this group
0:19:17 > 0:19:20ensured lots of fish made it out alive.
0:19:20 > 0:19:24It's very difficult to call a clear winner in this contest.
0:19:24 > 0:19:27The Humboldt squid managed to eat its fill,
0:19:27 > 0:19:31but there was still plenty of fish around to manage to breed
0:19:31 > 0:19:35and bring on another generation of fish, so they succeeded too.
0:19:35 > 0:19:37Strength in numbers worked.
0:19:37 > 0:19:41I guess the only fair result for this is to call it a tie.
0:19:41 > 0:19:42So the fish -
0:19:42 > 0:19:44Speedy swimming skills,
0:19:44 > 0:19:47a lateral line detection system,
0:19:47 > 0:19:49and strength in numbers.
0:19:49 > 0:19:52And they were up against the Humbolt's teamwork,
0:19:52 > 0:19:57rapid-fire arms and tentacles and that flesh-slicing beak.
0:19:57 > 0:19:59The squid may have got their meal
0:19:59 > 0:20:02but the shoal was large enough to take the hit
0:20:02 > 0:20:06so this time the honours were even.
0:20:06 > 0:20:08And this is our last deadly duo
0:20:08 > 0:20:10locked in a battle for life or death.
0:20:10 > 0:20:15Representing the predators, it's the cuttlefish.
0:20:15 > 0:20:20It looks like an alien from a horror film and it kills like one too!
0:20:20 > 0:20:24And up against it is this.
0:20:24 > 0:20:28A shrimp - it may be small, but it's armed with a secret superpower.
0:20:28 > 0:20:32But which animal has the edge in the race for survival?
0:20:32 > 0:20:34It's time to go 360.
0:20:38 > 0:20:43Again, we join the hunt in its final stages.
0:20:43 > 0:20:46The cuttlefish is moving towards its prey.
0:20:46 > 0:20:50The shrimp's either unaware or unconcerned.
0:20:50 > 0:20:53But it only has moments left to react if it's to survive.
0:20:56 > 0:20:59By now you know there's a lot more to a hunt
0:20:59 > 0:21:01than just the final strike.
0:21:01 > 0:21:04What are all the hidden factors that influence
0:21:04 > 0:21:06what happens in the next few seconds?
0:21:06 > 0:21:11To find out we have to wind back to the start and dissect the action.
0:21:11 > 0:21:14Let's start by checking out the location.
0:21:14 > 0:21:17For this final hunt we've moved to the North Sea, here,
0:21:17 > 0:21:19just off the coast of Denmark.
0:21:19 > 0:21:23We're in the shallows, not far offshore.
0:21:23 > 0:21:26The seabed's littered with rocks
0:21:26 > 0:21:28so plenty of hiding places,
0:21:28 > 0:21:32but also lots of good spots to set up an ambush.
0:21:32 > 0:21:36So that's the location. Let's meet the animals.
0:21:36 > 0:21:39First our predator.
0:21:39 > 0:21:42The cuttlefish has those trademark cephalopod arms,
0:21:42 > 0:21:46two hidden striking tentacles and a razor-sharp beak.
0:21:46 > 0:21:49Plus, it can do some incredible things with its eyes
0:21:49 > 0:21:52and its skin - more on those later.
0:21:52 > 0:21:56So it's clear, we're dealing with another well-equipped predator.
0:21:56 > 0:22:01But how's our prey going to try and neutralise the threat?
0:22:01 > 0:22:03Well, the shrimp is small and quick.
0:22:03 > 0:22:07Their main defence is an impressive camouflage technique
0:22:07 > 0:22:11which makes them very hard to spot, let alone catch!
0:22:11 > 0:22:15With two such talented animals, this hunt is going to be close.
0:22:15 > 0:22:17Let's see what happens.
0:22:17 > 0:22:21We're now right back at the start of the hunt.
0:22:21 > 0:22:24The cuttlefish is patrolling its territory,
0:22:24 > 0:22:27which can cover up to 20,000 square metres,
0:22:27 > 0:22:32meaning a lot of places for a tiny animal like a shrimp to hide!
0:22:32 > 0:22:36There aren't many signs of life at the moment, or are there?
0:22:36 > 0:22:39To get the full picture, we need to zoom in.
0:22:39 > 0:22:42You can see the shrimps have been there all along,
0:22:42 > 0:22:46but from this close, you can see why they're so hard to detect.
0:22:46 > 0:22:51They're practically see-through. How do they manage that?
0:22:51 > 0:22:55Usually in nature, camouflage is about disguising yourself
0:22:55 > 0:22:57to look like your environment.
0:22:57 > 0:22:59But the shrimp goes one better.
0:22:59 > 0:23:02When you look at it, you can see the environment
0:23:02 > 0:23:05it lives in and there's an interesting reason -
0:23:05 > 0:23:09the exoskeleton of a shrimp is made from the same material
0:23:09 > 0:23:12you'd find in an insect's exoskeleton,
0:23:12 > 0:23:14but it's very thin and pliable.
0:23:14 > 0:23:16The shell is transparent,
0:23:16 > 0:23:18and the blood's colourless,
0:23:18 > 0:23:23so you can see through the shrimp to the world beyond.
0:23:23 > 0:23:27It is pretty much invisible, incredible!
0:23:27 > 0:23:29So, certainly not helpless.
0:23:29 > 0:23:32Let's return to the action.
0:23:33 > 0:23:35There are loads of shrimp in the area,
0:23:35 > 0:23:39but with their powers of speed and invisibility,
0:23:39 > 0:23:42they seem unconcerned there's a predator nearby.
0:23:42 > 0:23:46So, is this hunt over before it's even started?
0:23:46 > 0:23:47Well, no, of course not,
0:23:47 > 0:23:52cos the cuttlefish has its own special superpower at its disposal -
0:23:52 > 0:23:54Its eyesight. The cuttlefish's vision
0:23:54 > 0:23:57is some of the most highly developed
0:23:57 > 0:24:00of any animal in the whole natural world.
0:24:00 > 0:24:04They can see well beyond the range of human vision,
0:24:04 > 0:24:07in particular, they can detect light that has been twisted.
0:24:07 > 0:24:10This is called polarisation.
0:24:10 > 0:24:14It's what happens to light waves hitting the transparent shrimp.
0:24:14 > 0:24:16They might be nearly invisible to us,
0:24:16 > 0:24:20but to a cuttlefish, the shrimp stand out in sharp contrast
0:24:20 > 0:24:24to their background, making them easy to identify.
0:24:24 > 0:24:26So the shrimp's cover is blown,
0:24:26 > 0:24:30but the cuttlefish still has to get within striking range.
0:24:30 > 0:24:34That's difficult for the conspicuous cuttlefish
0:24:34 > 0:24:36and the shrimp has very sharp eyesight.
0:24:36 > 0:24:39So how's it going to manage it?
0:24:39 > 0:24:42The cuttlefish's ability to change colour
0:24:42 > 0:24:44has no equal in the natural world.
0:24:44 > 0:24:48It's achieved in much the same way as other animals
0:24:48 > 0:24:50such as chameleons.
0:24:50 > 0:24:52Beneath the surface of the skin
0:24:52 > 0:24:54are special colour-containing cells,
0:24:54 > 0:24:58but what's unusual is how quickly the cuttlefish does it.
0:24:58 > 0:25:01This is unbelievably dramatic,
0:25:01 > 0:25:05look at this - the entire colour has changed in a second.
0:25:05 > 0:25:09There are also special bunches of muscles at the skin
0:25:09 > 0:25:14which can be used to draw up spiky shapes or make it smooth.
0:25:14 > 0:25:18So it uses these in tandem to create incredible camouflage,
0:25:18 > 0:25:22blending in perfectly with its background.
0:25:22 > 0:25:25Let's see how it puts these into effect.
0:25:27 > 0:25:31The cuttlefish used its remarkable eyes to pick out and target
0:25:31 > 0:25:32a single shrimp.
0:25:32 > 0:25:35Now it'll use that camouflage
0:25:35 > 0:25:39to try to get close enough to make a strike.
0:25:39 > 0:25:42First it will use that remarkable colour change
0:25:42 > 0:25:43to match its environment.
0:25:43 > 0:25:47It'll twist its tentacles to create weird shapes.
0:25:47 > 0:25:49Next it'll control its buoyancy
0:25:49 > 0:25:52to use the current to float towards its prey.
0:25:52 > 0:25:56It'll use that siphon to adjust its trajectory.
0:25:56 > 0:25:58So there's very little turbulence
0:25:58 > 0:26:01in the water for the shrimp to sense.
0:26:01 > 0:26:03To fully appreciate all this, though,
0:26:03 > 0:26:06we need to see things from the shrimp's point of view.
0:26:06 > 0:26:08Let's go to shrimp-cam!
0:26:08 > 0:26:13All the shrimp can see is floating weed, drifting closer -
0:26:13 > 0:26:15a brilliant disguise.
0:26:15 > 0:26:20Now the cuttlefish has plenty of time to lock on target,
0:26:20 > 0:26:23extending its two striking tentacles, and...
0:26:24 > 0:26:25Wham!
0:26:25 > 0:26:27Let's see it again.
0:26:27 > 0:26:30After such a slow and considered approach,
0:26:30 > 0:26:33the final strike was devastatingly quick.
0:26:33 > 0:26:35Let's see it from shrimp-cam.
0:26:37 > 0:26:40This is the last sight the shrimp will see.
0:26:40 > 0:26:43It's snatched up by those tentacles,
0:26:43 > 0:26:45dragged back by the arms to the mouth,
0:26:45 > 0:26:51eaten, and then the cuttlefish heads off to find another victim.
0:26:51 > 0:26:55It'll take more than a bit of see-through camouflage
0:26:55 > 0:26:57to outwit the cuttlefish.
0:26:57 > 0:27:01With its incredible skills and techniques,
0:27:01 > 0:27:04it's one of the most accomplished hunters on Deadly 360.
0:27:04 > 0:27:08So, the shrimp had its small size, sharp vision,
0:27:08 > 0:27:11and an almost invisible body.
0:27:11 > 0:27:17But the cuttlefish overcame these defences, with its all-seeing eyes,
0:27:17 > 0:27:21clever camouflage techniques and devastating final strike.
0:27:21 > 0:27:24The cuttlefish always had the advantage.
0:27:24 > 0:27:31Despite being almost invisible, the shrimp just never saw it coming.
0:27:31 > 0:27:36The squid, octopus and cuttlefish are continually-surprising animals.
0:27:36 > 0:27:40They have an unparalleled ability to change their shape and colour.
0:27:40 > 0:27:44Some have venom and sharp biting beaks, and in their element,
0:27:44 > 0:27:46they're truly lethal killers.
0:27:46 > 0:27:48That's all we've got time for.
0:27:48 > 0:27:52Join us next time, as three more pairs of animals go head-to-head
0:27:52 > 0:27:56and we analyse the action, Deadly 360 style.
0:28:05 > 0:28:08Subtitles by Red Bee Media Ltd
0:28:08 > 0:28:11E-mail subtitling@bbc.co.uk