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[♪ INTRO ]
Close your eyes for a second and picture the most fearsome predator you can imagine.
What did you think of?
Maybe a lion?
A golden eagle?
A rattlesnake?
Those animals may be fierce, but it turns out that when it comes to hunting prowess,
they aren't very impressive.
Solo lionesses catch the prey they pursue only about 2% of the time, and when they work
together, they still only succeed at around one in every four hunts.
Golden eagles succeed in one out of five tries.
And those snakes?
Their strikes miss more often than not.
That's downright pathetic compared to the near-perfect catch rate of the humble dragonfly.
When you look at the numbers to find the planet's most efficient hunters, most aren't exactly
species you might think of as cold-blooded killers.
But the animals on this list are hunting machines, each with a success rate of 60% or more.
[1.
Black-footed Cats]
Big cats like lions, tigers, and leopards are among the most feared predators, and for
good reason—all cats are obligate carnivores, meaning they need to eat meat to survive.
But the most efficient hunter of the group is actually Africa's smallest feline: the
black-footed cat.
At only 2-2.5 kilograms, these kitties might look like small, stocky house cats, but don't
let their size or cute little furry faces fool you.
They're ruthless killers that capture 60% of the prey they target!
And that makes them at least twice as efficient as most other cats.
The closest contender would be cheetahs, which successfully chase down about half of their
targets.
But black-footed cats don't need speed.
Instead, they rely on stealth.
These cats are nocturnal, so they can use the darkness to their advantage.
Their small size also helps them stay hidden in the short shrubbery of the arid habitats
they call home.
That way, they can silently stalk their prey until they're close enough to pounce.
Individual cats have been observed killing 10-15 small mammals and birds in one night.
And they don't balk at attacking prey that's bigger than them, either.
There's a local legend that tells of a black-footed cat killing a giraffe by slicing its jugular
vein — which...
probably didn't happen, but it speaks to their fierce reputation.
Unfortunately, bravery and ruthlessness aren't enough to save them from poachers, habitat
loss, or car tires, and they're currently classified as vulnerable to extinction.
They're not going down without a fight, though.
Researchers have seen adult cats circled by jackals five times their size, fight to survive,
and win.
[2.
African Painted Dogs]
The members of the family Canidae also have a pretty fierce reputation — think wolves,
dingoes, and coyotes.
But most are kind of meh hunters, with success rates of 35% or less.
Except for African painted dogs, that is — they kill 70-85% of the prey they hunt.
And teamwork is the secret to their success.
While many canids live in packs and coordinate hunts, African painted dogs are so dependent
upon one another that lone animals probably don't survive long.
And their one- to two-dozen dog packs are surprisingly egalitarian.
There's less animosity between individuals than in other pack-forming species — especially
at meal time, when younger animals get first dibs.
They'll also bring food back to the den for pups too small to join in the hunt and
adults with injuries.
Studies suggest they even make certain decisions somewhat democratically.
And being such close-knit social animals likely leads to better coordination between individuals
when they're hunting as a group.
Packs work together to take down large prey, including antelopes, zebras, and the occasional
wildebeest, relying on the stamina of the group rather than the element of surprise.
They've even learned how to turn man-made barriers like fences to their advantage.
In fact, their killing prowess is so legendary that it used to make them the bane of farmers
and ranchers.
So painted dogs were poisoned or shot on sight to protect livestock, which is the main reason
why there are only several thousand of these now-endangered animals left.
Another problem is that even though they're skilled, efficient hunters, their tactics
are also time-consuming.
And that may ultimately cause their demise as climate change leads to more periods when
it's too hot for such long hunting trips.
[3.
Ospreys]
Raptors, aka birds of prey, are all fierce hunters that rain down terror from the skies.
But being talented hunters doesn't always mean they're efficient, and most raptors
usually fail to catch their targets — except for the ones that fish.
Ospreys are the most efficient birds of prey in the world, catching their meals 80-89%
of the time.
With wingspans of almost two meters, they're gigantic, and you can find them near bodies
of water almost anywhere in the world.
Bald eagles, which are also big, fish-loving birds, are almost as talented, with a success
rate of about 80%.
The efficiency of both birds probably comes from their shared taste for aquatic prey.
When fish rest near the surface, pack themselves into dense schools, or hang out in shallower
waters, they're easy pickings for aerial hunters.
And both species tend to target bottom-feeding fish, which are generally slower-moving and
may spend more time looking down at their potential meals than watching for predators
from above.
Of course, finding slippery prey like fish is only half the battle — ospreys also have
to keep ahold of their meals until they can find a suitable spot to land and feast.
So ospreys have scaly skin on their feet for extra grip, and their large, curved talons
both cling ato and pierce their prey — especially when they rotate their special fourth toe
to grasp extra tightly.
They can even snag two fish at once — one in each foot.
Hunting doesn't get much more efficient than that.
[4.
Harbor Porpoises]
If you thought those crafty orcas that knock seals off ice or go onshore to grab pups from
the beach would be the most successful cetacean hunters,
well, sorry.
You're thinking too big.
Because the most successful hunter among the whales and dolphins is the sweet little harbor
porpoise, with a success rate of over 90%.
The harbor porpoise tops out at around 80 kilograms and is less than 2 meters long from
nose to tail.
In addition to being small, they're pretty shy — which is maybe why you've never
seen one, even though they're common in coastal areas across the northern hemisphere.
They also spend pretty much all day hunting, because they need to eat 10% or more of their
body weight every day.
Their small size means both a higher metabolism and greater susceptibility to cold, so they
need to burn a lot of calories to keep warm in the chilly waters they live in.
If they go a day without eating, porpoises can get visibly thinner, and after three days,
they die.
Of course, when you need to eat that much, it helps to be an efficient hunter.
Exactly how they're so much more successful at catching their prey isn't clear, but
it might have something to do with the way they use sound while hunting.
Like many of their relatives, they find and track the fish they eat using echolocation.
And also like many of their relatives, when they get near their targets, they emit a series
of super-rapid clicks called a "buzz".
But harbor porpoises buzz at more than 500 clicks per second, which is over three times
the rate recorded from orcas hunting fish.
And it's possible those super-fast clicks give them a more accurate picture of their
prey.
It also probably helps that the fish can't really hear these clicks, so they don't
necessarily realize the porpoises are getting close.
However they do it, porpoises manage sometime to eat upwards of 550 fish an hour — an
entire order of magnitude more than estimates for other cetacean species.
They're so ravenous, they've even been known to swim up into rivers to chase down
food.
They're basically miniature, hangry dolphins.
[5.
Dragonflies]
To us, they might look pretty, or sometimes goofy, but dragonflies are strong contenders
for the insect world's best hunters.
Their larvae terrorize small fish, tadpoles, and aquatic invertebrates, and the adults
are ruthless aerial hunters that catch 95% or more of the bugs they chase.
Their large eyes, which have around 30,000 facets, give them 360 degree vision, so nothing
moves without them knowing.
They also have specialized pigments that detect a wide variety of colors, and the tops of
their eyes are extra sensitive to blue and UV light, which helps give them better contrast
for spotting prey against the sky.
Once they find a target, they can selectively focus their visual attention, much like we
can, to keep track of its every move.
Then, they take to the air.
Dragonflies can chase down their meal at up to 55 kilometers an hour.
And their four wings give them incredible maneuverability, even compared to other super-agile
insects.
They can fly forward, backward, straight up and down, side to side, upside down, rotate
on a dime, or simply hover and wait for the right moment to strike.
When they do go in for the kill, they don't aim themselves at their prey directly.
They actually intercept their targets in midair by predicting where they'll go with a special
neural circuit in their brains — which is part of why they almost never miss.
All these special adaptations make dragonflies into impeccable aerial assassins.
Which might explain why they've been around for some 300 million years.
[6.
Leatherback Sea Turtle]
Venomous snakes might be the deadliest reptiles on the planet, but they're far from the
most efficient.
There is a reptile, though, with a perfect record: the leatherback sea turtle, which
catches and consumes every single bit of prey it targets.
In a way, that makes it among the best hunters in the world.
That might be because leatherbacks only eat jellyfish, which aren't exactly the fastest
moving prey on the planet, but with their tentacles covered in millions of venomous
stinging cells, jellies are still a formidable food item.
And they're not very nutritious, either.
Leatherbacks need to eat enough calories to fuel their massive bodies, which can be over
2 meters in diameter and weigh 900 kilograms.
That's a lot of jellyfish.
Luckily, the leatherback sea turtle is a giant, jelly-killing machine.
They can dive to depths of over 1100 meters in search of their prey, and can stay submerged
for nearly an hour and a half.
Once they find a juicy lion's mane or other jelly swimming around, they aim for the bell,
taking a big bite of the gelatinous body.
The unlucky jelly's stinging cells can't pierce the turtles' leathery shell and thick
skin, and all hope of escape is lost as soon as any part of the jelly enters the turtle's
mouth.
Large, hardened spines called esophageal papillae ensure that nothing that goes in can leave,
even when the turtle is spitting out excess water it swallowed.
The turtles are such good jelly-hunters that they can consume nearly double their massive
body weight in jellies every day when there's a bloom.
Unfortunately, the turtles aren't so great at telling the difference between tasty jellies
and not-so-tasty plastic bags, which can cause fatal blockages in their intestines.
Which means the leatherback's efficient jelly-hunting might be its downfall — unless
we get our plastic pollution in check.
So, like the other species on this list, the leatherback might not be the most terrifying
animal on the planet.
But as hunters, they outperform their deadliest relatives.
It just goes to show: you can't judge the best assassins by their looks.
But sometimes judging something by its looks is really important, like when you're applying
for a job or a program and you need a professional portfolio.
But what's the exact purpose of the portfolio?
What should you include?
And how do you organize it all?
Well, if you've wondered these things, check out Sonia Nicolson's Skillshare class "Portfolio
Preparation."
There, she guides you through choosing a focus for your portfolio and the step by step process
of creating and submitting one.
We'll link to her class in the description as well as a special offer from Skillshare.
Right now, Skillshare is offering SciShow viewers two month s of unlimited access to
Skillshare for free.
Just click on the link in the description to check it out.
If you like learning with us at SciShow, we think you'll also enjoy Skillshare classes
and all this week we're working with Skillshare to highlight fun and challenging classes.
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