BBC Earth 50 Top Natural History Moments | 30-21

spider silk with the scent of a female, you just need to follow her wherever she leads, other males have undertaken the same quest and met a gruesome end. Here is the female and she doesn't seem very loving, in fact she kills all the males. Who doesn't meet her expectations, what can she do to win her over? dance dance for life she will need a spectacular trick to avoid becoming a lunch with her fan deployed he begins a series of increasingly complicated dance moves to try and seduce her, finally she succumbs to her advances and allows him to mate with she.

He lived up to her expectations, but she kills him anyway. The Namib Desert, one of the most exposed places on

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as the sun rises high, protects everyone from the extreme heat. all except the hot rod and while others take shelter their day is just beginning to clean the nest the sun can reach a scorching 70 degrees Celsius the long legs of the ants raise their bodies above the surface where it is 10 degrees cooler but if they stay still will fry must keep moving or risk the same fate as their prey creatures that have collapsed from heat stroke buried too deep but would be a place to cool down foraging decisions must be quick to be perfect return to the nest before let them also die but they strayed into a minefield each of these strange tone-shaped pits is a death trap with a brutal predator in the center here lives antlion larva small ambush predators with pincers full of poison some ants managed to escape but the antlion has other tricks, throwing sand into the air creates an avalanche in This cone of death, the walls are so angled that the sand slides under the ants' feet while rocks rain from the sky.

It seems almost impossible to escape. Few northern Australia have the highest tides in the tropics, revealing vast areas of coastline and a truly extraordinary species lives here. octopus octopuses are marine animals that live and breathe underwater during low tide most octopuses will be trapped in their rocky drink but this is no ordinary octopus, it is the only one specially adapted to walk on land, crawls using hundreds of small suction cups he lines his arms looking for crabs he walks from pool to pool a pot full of quite scared fish this one is empty so the octopus moves a rude fool it may seem like a safe haven but the octopus's suction cups allow him move as stealthily in as out of the water this is no place safe when this octopus is in Papua New Guinea the bower bird has lovingly rebuilt and redecorated its intestine another visitor this time it's a female this is just where he wants her to start the show first he expands his pupils alternately it is a strangely fascinating display a warming point accompanied by a strange, hissing call from deep in his throat now it is time for his big performance he flaps his wing like a matador's cape she seems to be paralyzed this certainly draws attention but it seems he needs to do it more generously, she drops a hint: he's the bird equivalent of a bouquet of flowers, everything is going so well it's time to get physical with some headbutts to the chest, one last flourish to crown weeks of effort, but something is wrong, his rival is behind and at the worst possible moment, what should he do for the female?

The moment is gone, sometimes no matter what you do, things just don't work as our brains are flooded with information about patterns and colors through Callie's eyes, rapid movement trumping all as she stalks. Like flies, their eyes send signals to the brain's visual cortex, which analyzes what has changed from one image to the next up to 70 times per second faster than the human brain and a much larger proportion of the neurons in Callie's brain. They are dedicated exclusively to detecting motion, you almost can't help it, but the wild ancestors of cats in pants relied on low-light vision and the ability to detect motion to stalk their prey, but these evolutionary adaptations have a downside : Cats cannot focus on anything closer than about 30 centimeters in front of them.

But when their eyesight fails, cats have another sense perfectly adapted to going in for the kill. The team has organized an experiment to reveal how our cat's secret weapon works, so that the camera can record in Full HD resolution up to 2700 frames per second. Thought 2030 Times We'll Get It John Bradshaw hopes these ultra-high-speed cameras will capture this extraordinary sensory organ in action. It really is very, very fast. I've seen pictures of what happens, but there's nothing like seeing it in full. movement, so I think we have it there, but it's very, very, very fast. John is trying to watch the cat's whiskers as they move toward the attacking position.

Let's take the toy away for a second and then we can see what we ended up with. taken well, here we go, the cat notices the masses within its pasture, but wants to know exactly where it is in relation to its mass, its eyes give up because they can't focus very close, that's where the whiskers come They take charge, so what can we do? Look here, the whiskers are suddenly dragged forward and now the claws are kicking in, so we get here. Look, the whiskers are pointing almost directly in front of the cat's nose, he's finally catching them with his claws as he moves around trying to catch them. mouse, but the small muscles at the base of each whisker are pulling very hard to move them forward completely out of the normal position.

Is it really that extraordinarily detailed? I never expected to see all this. Everything seems to take place in about a fifth. of a second that simply shows how fast cats' reflexes really are from the point where they sweep their whiskers forward with their muscles contracted and then relax back and the whiskers spring back again, the mass has no chance of being much thicker and longer than normal hares. The whiskers also lie three times deeper in the skin, where they attach to nerve endings, telling the cat how far each one bends back and how quickly its whiskers are the same width as its body, allowing cats to navigate the tightest of spaces.

Cats also have whiskers. above their eyes and on their ankles sending them a constant flow of information as they feel the world around them there will be no easy meals on this island walruses are the largest seals in the world they weigh more than a ton and are armed with one meter long tusks Long exhausted by his shrimp, the bear must regain his strength the next day. A sea fog envelops the island. Wallace's sense that they are in danger uses the fog to cover himself. The bear approaches the herd. The adults close ranks around their young, presenting a wall of Fatty and drugged, it tests the man, but he remains firm.

It seems the world's largest land carnivore has met its match. There must be one in the armor somewhere. This female walrus is protecting her cub. If you can tear it from the bear's claws and the teeth cannot penetrate its thick hide as the pack retreats to the water the bear must move quickly having failed with one it heads straight for another the chance of its first meal in months is slipping away it seems. increasingly desperate is now or never must the barbed fangs prevent him, if he is the winner, the flailing walrus is immensely powerful and drags the bear away from the shallows towards the safety of the herd, it slips out of his hands in This time of year, polar bears on average succeed only once in 20 hunts.

If the hunter is thin like this, it may not be frequent enough, all she can do is keep trying to keep her scent from betraying her. He makes a wide sweep to get downwind of the seal and toward us. Now he is right behind the seal. Incredibly, she caught the seals underwater. It's only small, but still, its fat alone will contain a hundred thousand enough calories to sustain the surplus for a week and in that time it might even catch another one, but this cannot go on forever as summer continues, temperatures rise Each hunt requires more energy.

Draining the bears of their reserves, the wolves in northern Canada are the largest and most powerful in the world and are spreading across the land. The herd is 25 strong, a sign that the prey they are looking for is formidable. These bison are even bigger. than their southern cousins ​​and North America's largest land animals for generations, the wolves and bison here have been shaped by their battles with each other, making each the most impressive of their kind the bison will not remain a long time in the trees, here they are not sure the wolves are getting closer, but their chance to ambush the bison in the forest has passed. their prey are now outdoors and grouped together for safety. the wounds will have to work as a team with them to kill.

They surround the herd. They try to destabilize it. and spit it out, but the bison are armed and dangerous, they will be safe as long as they stay together. The wolves step up their game, rushing the herd with a ploy to cause a stampede and spit out one of the smaller ones, around which the bison form a defensive circle. their young horns point outwards, the wolves need a bison to break the line, but the tables are turning and now the wolves have to retreat, they focus their attention on the back of the herd and the bison begin to panic, a Young bison lagging behind even this year.

It eclipses the words that run headlong through Hertz. The only thought is to escape. A stroke of luck for the wolves. The slaughter will feed the herd for several days, but then they will have to resume the chase that in the icy extremes of our planet the fight for survival never ceases. It's called Darwin's bark spider and the female has a remarkable strategy like a real-life Spider Woman: she sprays strands of silk in a long, continuous stream, the threads fan out like a sail and float on air currents. that blow over the water every few seconds. the threads together to prevent them from spreading too much the breeze will do the rest by blowing the threads in a single line and a 25 meter jumper must now reinforce his bridge because his net will hang from it but there is something that makes the line bounce at the other end Another Darwin spider is trying to take advantage of his hard work.

He must deal with the head of the intruder on the cutting line. It is an inconvenience but no more than that. With hopes that the tips of each leg meet in the thread, it will not go to waste, since he will eat it later, when it's all rolled up, she goes back to spraying jets from another 25 meter bridge line How a spider no bigger than a thumbnail can produce so much silk so quickly has baffled scientists and is not a Ordinary silk is the most resistant

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silk. The fiber of the planet is harder than steel and it must be difficult to cross the wide river with the bridge prepared and the ground anchor in place.

It's time to build her trap. These spiders can build the largest orb webs in the world, up to 2 meters wide. hours since the first spray of the bridge line, the job is done now your strategy is to simply sit and wait and there is one last episode of silk production wrapping your food for later, it is early morning and the ticker sees a strange cat black on a nearby roof and Hearing this screeching may simply be a sound of frustration, but no one is really sure. Rocky, out for an afternoon walk, makes this noise when another cat blocks his path, but the

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of feline communication is much more surprising than this.

There is a noise we hear. I've barely heard that it rarely happens when cats go out together to understand what's going on, we have to go back to the beginning and the youngest members of the study, biologists dr. John Bradshaw can explain why these 1-week-old kittens meow. The meow begins as a kitten vocalization. It is something that kittens use to call their mothers and, as you can see, it is very effective in keeping the mother very attentive to them. meows and then as the kitten grows it gradually stops meowing, presumably only because the meows stop working the mother wants to wean the kitten and it stops responding with a pet cat that constantly meows at its owner is a form of attract the attention of the owner, that's because we are not very vigilant creatures we spend a lot of time with our nose buried in books, computer screens or televisions and the cat each cat learns independently we believe that using this kitty behavior is a good way to get our attention, so meow It's good for us to look up and find out what they want from us.

There you have it, Henry, so cats have two different languages, one for each other and one for us. Scientists have discovered that cats make a wide variety of meows and I wondered if there was aUniversal language for cats and humans. There is a troll. That was enough. If that is all. They make that funny little noise. It makes scientists discover that each cat's meows are unique. Each cat learns which noises work best in certain situations and develops a special language that only its owner will understand when they want food it's a much longer meow hungry Oh Miss Piggy learned to say milk so she doesn't prefer milk meow meow yes what's cute and When cats meow there is one thing that almost every owner in the study said yes, did you go hunting today?

Answer well, you are great, your mom is beautiful, do it big, see you, lovely girl. Yes, talking comes

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ly to us and every kitty that spends time with people learns that to communicate with us. have to make a noise