Waves crash with the power of a battering ram. Little survives a direct onslaught. Mountains erode in their wake. As humans, we're acutely aware of the devastation the ocean delivers. 800 times denser than air, it packs a punch. So how do creatures live inside the monster? One design evolved to thrive in the ocean. The fish shape triumphed. With over 500 million years of inspiration, fish turned ocean challenges into opportunities for speed. Their internal organs fit into a compact, streamlined body. One of their engineering secrets is the swim bladder. It absorbs or releases air to control buoyancy.
Since the swim bladder keeps it afloat, the fish can use all its muscle power for propulsion. And the driver for this liquid speed is the tail... Where nuances in structure determine the tradeoff between maneuverability and speed. A broad tail with a large surface is great for 180s and quick starts but not for sustained speed... While the split tail is extremely fast over long distances but useless at tight turns. One tail offers the best of both worlds. The forked tail has a large surface for agility, but it's split for speed and endurance, too. Here, form follows function because this tail is perfect for communal living.
And 80% of fish congregate in schools. It's a survival tactic. If you stick together, you confuse predators. But safety in numbers only works if you're coordinated. And a forked tail allows for quick reactions to direction changes. Sardines are the proverbial experts, gathering in schools of millions. With sideways facing eyes, sardines react immediately to the movements of a next-door neighbor. The downside to group living: Everything wants to eat you. Sardines set the bar high, but one group of killers easily meets their challenge: Game fish are the speed demons of the ocean.
And top spot goes to the sailfish. As fast as a cheetah, the sailfish can catch anything he wants to. And right up there, clocking an impressive 55 Miles per hour, is the tuna. Both the sailfish and the tuna sport a speedy Crescent tail. A narrow base with hardly any surface area means drag is reduced to power the fish forward. When these speed racers set their sights on sardines, the little fish don't stand a chance. Other predators appreciate the moving banquet. Sharks are also powered with a Crescent tail, but additional features enhance their performance.
Their skin is covered in minute tooth-like structures that fit together like roof tiles, so water slides right off this smooth enamel surface. Muscles attach directly to this external skeleton so movement converts immediately to thrust. This lateral line, a unique sense organ, detects the tiny electric impulses from individual fish within a school. Sharks' eyes adjust for low light... vital for hunting sardines. Sharks don't nibble at the edges like game fish; They dive into the middle of the feast. Equipped for speed in the darkness, sharks can take advantage of the mother lode. Pupils dilate, and a mirror behind the retina pumps in additional light.
Their fishy sixth sense transmits the timing for the strike. Sharks are top-notch hunters, but there's a superior sardine chaser out there. These killers are not fish. They don't react to prey; They control it. A dolphin's fundamental improvement is internal. Their mammalian brain allows them to strategize. They whistle and communicate with each other to plan their attack, and it's this tactical advantage that makes their speed formidable. Head-on at 29 Miles per hour and no collisions. There's nothing impulsive about their sardine hunt. Teams are responsible for specific tasks. Some blow walls of bubbles to sow confusion. Others circle the school to drive fish into a tighter bunch. And one team will swim into the middle of the sardines to feed.
Instructions are given... And the hunt begins. A quick whistle and the dolphins swap roles so everyone can eat. Marshaled by the dolphins, the sardines are assembled for another assault. It's the airborne division. Plunging down more than three stories, cape gannets dive bomb the sardines. Beneath the waves, bird morphs into fish. Wings and feet are fins and paddles. Gannets hold their breath for 40 seconds, so if they don't hit their target on impact, they just give chase. Speed and surprise outmaneuver their prey. Most fish are swallowed before they return to the surface. Their pace underwater comes from the height they drop. 100 feet up to be precise. When they spot the sardine shoal, their attack begins. Gannets take the gold medal for diving.
They strike the water at a bone-crunching 60 Miles per hour. That's the speed limit in Arkansas! For maximum acceleration, they streamline their bodies. Wings and feet disappear, so it's a javelin-spear that pierces the water. But it takes more than aerial contortionism to make a diving champion. They plummet headfirst. That's instantaneous whiplash, fracture, and concussion for an unprotected human. Gannets' safety features come standard. Its beak has no external nostrils into which water might be forced. An extra thick skull bone acts as a crash helmet, and air pockets inside the skull protect the brain like bubble-wrap. They throw themselves into a backwards dive to slice the ocean.
Horizontal momentum flips to a vertical drop. Head and body align in an arrow-like posture. And the shock of the impact is absorbed by the air pockets. This five-star safety design works unobtrusively to maximize speed. If sardines are near the surface, it's an instant meal. But gannets are also equipped to swim for supper. When the reward is great, squadrons of gannets rain down. Despite their skill in the water, adult gannets don't live at sea. Home is a short haul flight away. So after a short break, it's time to whip out another specialty: A water takeoff. And not off a calm ocean. The rougher the better. Webbed feet, which disappear for an efficient dive, now push against the ocean like a solid surface.
Running on water builds momentum, but it's the ocean winds that provide the lift. Carried by the breeze, they fly... As a bird is born to do. Home is a rocky island barely jutting out of the sea. But finding your place in the crowd can be downright dangerous. 70,000 gannet nests cram onto a site the size of a baseball field. You can't blame a guy for getting lost. Eyes that accurately target a fish underwater are confused above this ocean of white. He's listening for the "All clear" From his ground crew. But it makes sense to maintain a holding pattern till you're certain. There'll be hell to pay if he ends up in the wrong hood. With nests only pecking distance apart, it's a common problem. Intruders pay for their mistakes.
This male is lucky to escape with his life. Eventually he sees something he recognizes... His chick and mate, impatient for his return. He's brought lunch in his belly, and his youngster wastes no time helping himself. Four inches of beak ram straight down dad's throat. It's a good thing he's an expert fisherman. Junior will demolish three bellyfuls of sardine every day for three months. With dad on feeding and babysitting duties, mom must catch the next meal. Taking off from this island is tough with no wind and no space. Gannets are terrible at vertical takeoff. So despite the overcrowding issue, they've built an airstrip... 33 feet of runway on the edge of the colony.
They have to create their own wind. With a running start, they can generate enough momentum for liftoff. But even that's no guarantee. A quick equipment check, and our mom's ready. Claws grip the track like cleats for traction. Each downstroke of her wings provides upward thrust. Then the physics of flight kicks in. Lift overcomes weight, and she's airborne. Just offshore, silhouettes of grace and beauty dance. An air-breathing mammal, completely at home in this watery world. Humans are drawn to these sea dogs because of all the ocean's creatures, seals know how to have fun.
They dedicate speed and agility to playtime. Seals celebrate the sheer magic of being underwater. And their games of loop-de-loops happen at 10 Miles an hour. Families come together in the safety of the shallows and practice moves they'll need in the open ocean. To a seal, rough conditions are opportunities for a surf. The reason for this ease underwater is an extremely flexible spine with bones that can twist like a corkscrew and back again.
Extra-large neck vertebrae and thick muscles means there's no narrowing at the neck. The head flows into the body for a perfectly hydrodynamic profile. Seals are one of the most agile animals in the water. But this yoga-on-steroids has a darker purpose. Seals are killers, and every move they perfect makes them better at it. Games are over.
It's time to hunt. His destination: Gannet island. There's been a color shift in this neighborhood, and numbers are up 50%. Juveniles exercise madly for the biggest challenge of their life... Because this salt-and-pepper plumage means they're ready to leave home. It's a harsh jolt into adulthood. With no warning, gannet parents just stop feeding their youngster. Begging doesn't change anything. Today the cafeteria is closed. Many are in the same boat. From now on, if they want fish, they'll have to catch them. The clock is ticking. After 10 days without food, they'll die. Scraps won't cut it. To eat, they first have to fly. They haven't learned how to use the runway. So most youngsters wander to the edges of the island where the wind can give them a boost. It's a punishing location for flight school.
But starvation is a strong motivator. Wings that have never carried weight before test the breeze. Primal instinct fuels determination. And every wing beat builds confidence. They practice maneuvers they'll need in the air, flex muscles that must fly, dive, and swim. But exercising will only take them so far. They have to find food, or die trying. It's a disaster. They don't yet have the muscle strength. And there's just not enough wind for lift. Waves crash with the determination of a concrete mixer. Ocean speed conquers here. Now soggy wings have to master a water takeoff. And every dump saps more energy. Even if they make it back, there's no guarantee of success. Scavengers wait for them to quit. A quarter of all juveniles never make it off the island.
There are worse things than a rough ocean. And another reason for the gannets' terrible survival statistics. This shadowy specter capitalizes on the juvenile's disastrous flight path. Cape fur seals thrive in turbulent waters. And now the gannet knows he's being hunted. He tries to anticipate the seal's approach. Predator and prey face to face. A perfect strike. The gannet's going nowhere with a broken leg. Now the seal can take his time. It's no contest
against a sitting duck. As the gannet washes further out to sea, the seal can plan his deathblow. Neck muscles unleash with the intensity of a pit bull. Jaws clamp in a vice grip, and thrashing rips the gannet's body apart. Unable to chew, the seal must tear off chunks of flesh to swallow whole.
With the odds so violently in favor of the seal, the outcome was inevitable, but it isn't always the case. Beneath the waves, some juveniles fish with confidence. They've made it, despite the odds. In range of those beaks. Speed battles are not only fought on the high seas. Death occurs in unexpected places, too. This is not the tranquil paradise it seems. Coral reefs host one quarter of all marine species, but they're no sanctuary. And danger becomes visible when the action is slowed down. Millions of lives lived in close proximity comes at a cost. Everyone is a potential meal. One strategy is to keep moving. Or find somewhere to hide. Appoint a lookout. And take cover at the first warning. Speed can save your life. You don't have to do anything if you can't be seen.
One creature hides in plain sight. Every body part is disguised to mimic the reef. Skin is textured like coral-encrusted rock. And even eyes impersonate algae. Scorpion fish disappear into their surroundings. There are many varieties, but all have a single purpose: To ambush prey. Speed is their weapon of choice, but these predators keep that ability hidden, too. Some species remain motionless for days at a time, while others seek more favorable hunting grounds. Their strategy is patience... For the perfect opportunity. Nothing is what it seems. On the reef, these walls have eyes. The scorpion fish is hungry, but he has to wait for the fish to come closer. The frustration of the sit-and-wait predator... Beaten by a neighbor in the perfect location. The sneak on the left is a special type of scorpion fish, the aptly named stonefish.
There were two predators waiting all the time, and the stonefish lucked out. Prey vanishes in an instant. In less than one hundredths of a second, the fish is lunch. Their method is "Gape and suck." All scorpion fish expand the volume of their mouth and throat in a split second, with extra pleated skin concealed in their oral cavity. The difference in pressure between the inside of the mouth and the outside environment, vacuums prey in.
It's so effective that the water around the fish is like a solid object, sucked down the gape. The strategy is devastatingly effective when a fish swims into the strike zone. They do occasionally miss... When their lunge is too short... Or too ambitious.
When they're on form, death is instantaneous. When night descends on the reef, activity slows down for certain creatures. Some keel over for a quick 40 winks, or camp out with friends. One option is to sleep with eyes open, or grab an hour's nap between breaths. But nothing sleeps in the deep ocean. Down here, night brings murder. As the sun sets, millions of minute animals rise from the depths to feed. And predators follow. One hunter blends
into the darkness. But our cameras expose the invisible. Loligo reynaudii, a calamari squid. Prey never see him coming. Concealed weapons train onto his victim, accurate from three feet away. Capture tentacles explode in a quarter of a second. The mechanism is similar to toothpaste being squeezed out of a tube.
Crossed outer muscles compress and squeeze the inner muscles forward towards the prey. Over 50 suction cups on each club prevent escape. Food is shot straight back to his mouth at the base of the tentacles. And a parrot-shaped beak tears flesh into smaller, more manageable pieces. Food digested, the squid disappears to search for his next meal, but once a year, the tables turn. Hunter becomes the hunted. This orange garden becomes a battleground. These are not clumps of seaweed. They're egg sacks. Each finger-sized case is filled with hundreds of individual squid embryos waiting to hatch. Because at the beginning of summer, the squids leave the safety of their deep domain and gather in the shallows to spawn.
It's a stressful time. They're not top dog up here. Without the cloak of darkness, they're vulnerable. Only speed can save them. Their getaway strategy is jet propulsion. Water is sucked into the mantle cavity behind the head and expelled through the funnel in an explosive jet. Thick muscles around the mantle contract to force water out. Lightning-fast direction changes are possible with a quick swivel of the siphon. It's an impressive setup. Squids are three times faster than sardines. Speed makes them daunting predators in the dark and gives them a fighting chance in the shallows. But while these females are busy laying eggs, it's the perfect time for a hungry predator to catch them off-guard.
This ocean hoover may look lethargic, but he is capable of sudden bursts of speed, flapping his pectoral wings with enough force to create an audible bang. His isn't after the eggs. He combs the egg beds for careless females. This giant stingray is actively hunting. A squirt of ink distracts him momentarily. But he rallies and makes a kill. The squids don't hang around. They head for the safety of the deep, leaving their spawn to fend for themselves. Safe in their embryonic jelly, these juveniles are growing, unaware of the dramas playing out above their nursery. They hatch as complete replicas of their parents, with capture tentacles and siphons ready to propel them into the dark.
The reef is home to another unusual speed freak... a boxing champion with the fastest punch in the world. Yet this explosive violence is packaged in an unassuming lobster-like body. The mantis shrimp is neither mantis nor shrimp. It might look like its ocean cousin and pose like the land-living insect, but this critter is in a class of its own. These fists are looking for a fight. Hinged arms with clubs for boxing gloves unfurl as fast as a .22-caliber bullet... impossible to see at normal speed. Prey is quite literally smashed to pieces. It's the fastest move in the ocean.
And if you're that quick, you'd better have accurate eyesight. The mantis shrimp's vision is out of this world. It has the most complex eyes in the animal kingdom, with 12 different light receptors for color analysis... three times more than a human. It sees in all directions at the same time, with unsurpassed depth perception to accurately pinpoint prey. Bad news for this crab. A punch reaches speeds of 50 Miles per hour in 3 milliseconds... way faster than muscles alone could ever achieve. Their secret? A saddle-shaped part of the exoskeleton, which acts like a spring.
The mantis shrimp uses this spring and a latch mechanism to store energy, amplifying the strike speed generated by the muscles. A system of pivots at the leg joints further increases the blistering speed of the punch. Arm cocked, spring release, bull's eye at 73 feet per second. It's no fair fight. The crab loses by a knockout. Across the ocean, the rules don't change. From biggest to smallest, life is a race for survival, and speed can place you first or last. Ultimate fins. Dive bombers. Stealth attacks. With over three billion years to get inventive, ocean creatures have exploded the design envelope wide open.
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