Some Predators Are Born Knowing What to Do
Post on 26-Nov-2015
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Some predators are born knowing what to do. They are pre-programmed for the kill but others take a lifetime to learn. What does it take to become a predator?We uncover the critical events that shape the killer. Tropical rainforest, Ivory Coast, West Africa A hunting party is on patrolChimpanzees, five males in silence, they move on the forest floor, listening for their prey. This is what they are after colobus monkeys, feeding in the canopy, 30m up To catch them, these chimps have learned to hunt in the most extraordinary wayStealthily, the chimps take up position underneath their quarry. Colobus are light and agile so they can move in the thinnest of branches. The heavy chimp hasn't a hope alone but this is a team and each has learned its own specific roleThe driver, the blockers and the most experienced hunter, the ambusher working together, they have a chance. The driver makes the first move A young chimp, quite new to hunting. His objective is simple, to climb up beneath the monkeys and flush them outThe team watches from below, poised for action the hunter is on. The chimps in the ground immediately run ahead of the colobus the blockers are first in place. They anticipate where the colobus are heading and climb trees on either side. Older, more experienced than the driver , they must make themselves conspicuous ready to funnel the colobus between themMeanwhile back in the ground, the smartest chimp, the ambusher is on the move. His objective: to get even further ahead. He has seen the blockers go upand works out where the colobus will be funneled. He picks a strategic tree. He hides and waits. The trap is now set. The driver pushes the colobus onThey begin to scatter, but three seem to be heading straight into the trap. A gap in the canopy, the colobus are now getting away. The heavy blockers can't leap across, they must climb down in the last effort to reform the trap and back up again. Now the blockers are back on course another leap right into the ambusher's tree, the trap is sprungThe ambusher grabs, he misses, the colobus turns straight into the hands of a blocker. It's over. For the chimps, this is the triumph of generations of learning but you can't learn to hunt if it's not in your nature. For all predators, the story starts with the same basic thing: instinct, killer instinctThis ordinary garden wall is home to a predator whose life is ruled entirely by instinct Visitors to this wall must be careful, very careful. This is Amaurobius thorax, a common garden spider and she lives inside the wall. A month ago, she lays some eggs. Now they're hatching right on schedule.100 tiny spiderlings emerge from their egg cases. In a week, her offspring will become predators. But for now, they are too small to hunt for themselves. They must rely on mother. She lays a special sac of food eggs for them to eat - the spider version of milk., high energy to last them exactly three days.Then it's time for the next stage in the development. Spiders have skeletons on the outside. To grow,they must shed their skins, the spiderling's first moult. The moult signals the last of the dutiesof the devoted mother. Old skins discarded, her spiderlings are ready to grow some more, but again they need food, more than she can supply in eggs.She waits for the tick of her genetic clock, set for precisely one day after the first moult. Now she circles round the spiderlings, drumming on the web and spinning thread as she goes. The spiderlings swarm together, their killing instincts are aroused.Then a new behavior switches on, she presses herself down to her babies. They climb onto her, slowly at first, but soon they swarm. She has flicked their predatory switch and this is how she will feed them.
9500:08:30,700 --> 00:08:33,950She will be their first prey.
9600:08:36,400 --> 00:08:41,550With this moment,her spiderlings become predators
9700:08:42,000 --> 00:08:47,950As she succumbs to the venom,her life energypasses into her offspring.
9800:08:48,400 --> 00:08:51,250They suck the fluid from her body
9900:08:51,700 --> 00:08:55,850and it can even be seendraining from her limbs
10000:08:57,900 --> 00:09:01,350the ultimate maternal sacrifice.
10100:09:02,400 --> 00:09:06,250The spiderlingshaven't had to learn a thingto become predators.
10200:09:06,300 --> 00:09:09,750Just like their mother,their genes write the plot.
10300:09:10,300 --> 00:09:11,750Now they have fed,
10400:09:11,800 --> 00:09:14,850they will face the outside worldwith instinct
10500:09:14,900 --> 00:09:17,550preprogrammed for the kill.
10600:09:22,600 --> 00:09:27,850For others, becoming a predatortakes more than just hardwired instinct
10700:09:31,300 --> 00:09:35,450In a summer meadow,an ordinary farm cat hunts.
10800:09:37,300 --> 00:09:42,550The grass is long,so it indentifies its preyby sound and smell.
10900:09:50,400 --> 00:09:53,650A vole somewhere in the grass.
11000:09:54,900 --> 00:09:58,550If anything can get it,this cat can.
11100:09:58,600 --> 00:10:02,150Even after thousandsof years of domestication,
11200:10:02,200 --> 00:10:06,750its predatory genes still talk to it.
11300:10:10,000 --> 00:10:14,250Like the spiderthis cat has the killer instinct.
11400:10:17,100 --> 00:10:22,350Silent, alert, supremely poised.
11500:10:23,500 --> 00:10:27,150The well-oiled creepof an ancestry of killers.
11600:10:29,000 --> 00:10:31,550She coils the predatory spring.
11700:10:45,000 --> 00:10:47,750The predator strikes.
11800:10:51,400 --> 00:10:53,950But she hasn't always been so good
11900:11:05,200 --> 00:11:08,550These kittens are just a day old.
12000:11:09,900 --> 00:11:12,950Without mother, they are useless.
12100:11:13,800 --> 00:11:15,250They can't walk.
12200:11:15,300 --> 00:11:17,750Their eyes aren't even open.
12300:11:18,900 --> 00:11:23,350Just like the young spiderlings,they are too small to be predators
12400:11:26,600 --> 00:11:29,350Growth, however, is rapid
12500:11:29,400 --> 00:11:33,350from fluff ball to minipredatorin just three weeks.
12600:11:36,100 --> 00:11:39,050But this is where spidersand cats differ.
12700:11:39,300 --> 00:11:42,450Though physically the catsare now quite developed.
12800:11:43,600 --> 00:11:46,750Their predatory programmingis incomplete.
12900:11:47,900 --> 00:11:51,750Now, to start developing, the mind.
13000:11:53,500 --> 00:11:57,250First their instinctmakes them curious.
13100:12:00,000 --> 00:12:02,550Instinct makes them play,
13200:12:04,000 --> 00:12:07,350play links body with mind.
13300:12:11,500 --> 00:12:17,250They start to look like predators,focused, fast, alert.
13400:12:18,200 --> 00:12:21,050But at this stage,the rules are simple:
13500:12:21,100 --> 00:12:23,450catch anything that moves.
13600:12:31,000 --> 00:12:35,750After all, they could be anywhereand anything could be prey.
13700:12:45,900 --> 00:12:49,250But a cat can't live onfeathers and stones
13800:12:49,300 --> 00:12:52,850this simple instinct needs a focus,
13900:12:54,000 --> 00:12:55,850enter mother.
14000:12:55,900 --> 00:12:59,350She now comes back from huntswith dead prey.
14100:13:02,000 --> 00:13:05,050This is the new focusof the kitten's play.
14200:13:13,900 --> 00:13:16,250The kittens get what she can catch,
14300:13:16,300 --> 00:13:19,650a sample of the world of prey outside.
14400:13:24,100 --> 00:13:29,650She's programming the predatory machinepreparing it for future hunting.
14500:13:30,700 --> 00:13:36,250Sight, smell, feel, taste,this is what should be eaten.
14600:13:38,100 --> 00:13:41,650For the next stage, live prey.
14700:13:44,300 --> 00:13:48,850Now the mind is focusedon specific preya lesson in handling.
14800:13:50,300 --> 00:13:51,750How fast does it?
14900:13:51,800 --> 00:13:54,350How does it move?How do you catch it?
15000:13:55,600 --> 00:13:59,550Without this training,kittens will never be good hunters
15100:14:01,200 --> 00:14:03,850This time the vole escapes.
15200:14:07,700 --> 00:14:11,750Finally into the fieldto put trainning into practice.
15300:14:13,900 --> 00:14:19,250They go into the outside worldwith skills that basic instinctcan't provide alone.
15400:14:20,300 --> 00:14:24,150They have the advantage of learning.
15500:14:36,900 --> 00:14:39,050The predator hunts,
15600:14:39,100 --> 00:14:42,050fueled by instinct,
15700:14:43,400 --> 00:14:46,650fine tuned by learning.
15800:15:11,100 --> 00:15:13,550But the world is full of surprises.
15900:15:13,600 --> 00:15:16,350They can't be prepared for everything
16000:15:18,400 --> 00:15:20,850That is the beauty of learning.
16100:15:20,900 --> 00:15:24,150It doesn't just stop with mother.
16200:15:33,500 --> 00:15:36,350Next time, he will be ready.
16300:15:38,100 --> 00:15:40,650In fact, as an adult,
16400:15:40,700 --> 00:15:44,550learning can seriouslyimprove a predator's life.
16500:16:00,700 --> 00:16:02,950This is a green heron
16600:16:03,000 --> 00:16:05,650and there's only one thingon its mind
16700:16:07,000 --> 00:16:09,450- fish.
16800:16:10,400 --> 00:16:13,550It's a small birdand can't wade very deep.
16900:16:14,500 --> 00:16:17,950But fish are loathto go to the shallows.
17000:16:18,700 --> 00:16:23,150Just like a fis