Name: ホグノーズからクモの尻尾まで。6つの崇高なヘビ (From Hognoses to Spider Tails: 6 Sublime Snakes)
Uploaded: 2021-01-14T10:29:13.000Z
Duration: 12 min 53 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

We've got episodes on venomous snakes, and poisonous snakes,

and we've even had some on SciShow as Talk Show guests.

But you might still think all snakes are basically the same.

You know, like, they're all just, like, this slender, muscular danger noodle.

So in this episode, we want to pay special tribute

to the incredible diversity of these legless creatures.

We're going to talk about 6 snakes with some extraordinary features.

Hognose snakes get their affectionate name from their enlarged rostral scale,

which is the plate at the front of a snake's nose.

That gives them their upturned noses which make them look,

And kinda like a pig's snout, their little snoots are great for rooting around in the soil.

The upturned nose acts as a shovel to move soil or sand out of the way as they make a safe burrow.

The snakes will bend their heads downwards and then wiggle them from side to side.

At the same time, their bodies move in wave-like motions to help them sink below the dirt.

Those piggish noses also help them find food.

They eat everything from lizards to small mammals, but a nose for digging

helps them most if they're looking for frogs and toads that spend part of the year underground.

Their fangs, which, like other rear-fanged snakes,

are located further back in their jaws than front-fanged snakes, are long and smooth,

so some scientists thought that they might be used for popping toads

that inflate themselves as a defense mechanism.

But a scientist back in 1976 measured how long the fangs would need to be,

1.38 cm on average, in case you were wondering,

which is much longer than the fangs actually are.

The hognoses's unique hiding and hunting behavior is pretty cool,

but they have another trick up their scaly sleeves.

When they feel threatened, they'll roll over on their backs and play dead, also called death feigning.

And hognoses really get into this dramatic act.

They will writhe around and stick out their tongues until whatever scared them is gone.

Way back in 1974 scientists noticed the snakes' heart rate would also drop while death feigning

from around 50 to 80 beats per minute to between 3 and 15 beats.

That is some dedication as a method actor!

Stiletto snakes might sound fashionable but that name

isn't because they have good taste in high-heels.

They are a burrowing group of snakes found mostly in sub-Saharan Africa.

There, they inhabit everything from deserts to rainforests.

And they're best known for their long, knife-like fangs that allow them to

Most snakes strike when their potential meal is right in front of them—but not stiletto snakes.

They'll slide up past an unsuspecting skink, lizard, gecko or mouse

and then whip their head backwards to lodge one of those long fangs in the prey.

It's such a unique movement done at close range

that some scientists prefer calling it “fang stabbing” rather than striking.

And it might sound like a weird way to hunt, but it's actually really useful

as it lets the snakes capture prey in tight spaces like tunnels or burrows.

It also allows them to release the prey really quickly,

because they don't have their whole mouth wrapped around it.

And that's important because some of the stiletto snakes' prey,

So they want to get in, deliver some venom,

and then back off until the toxins have done their job.

In fact, the snake's entire mouth is specifically adapted for this weird attack.

Stiletto snakes have a short jaw bone, fewer teeth,

and a snout that's tightly attached to the rest of the skull

so the jaw stays clamped closed when it's wiggling through tight spaces.

But this awesome ability and anatomy has its downsides.

Stilettos lack the teeth needed to do the usual pterygoid walk to swallow their prey.

That's where a snake will open its mouth and use specific teeth to hook

and then pull prey into its mouth step by step.

Which makes sense if you don't have, like, hands to shovel food in your mouth, like, awww, I do.

And even if they had those teeth, their jaws don't open wide enough to swallow food that way.

So stilettos have to do a weird head wiggling action where they shift their jaw backwards,

flex their head down toward their belly and squeeze their trunk forward,

then shift their jaw and head forwards over their prey.

And according to scientists this is pretty much as extreme as this adaptation can get.

Basically it can't really improve upon its unique strike without sacrificing the ability to eat.

The Pseudocerastes snakes of the Middle East range from southern Israel,

through Iraq, southwestern Iran and Afghanistan and Pakistan.

They get their scientific name from the false horns on the top of their heads,

but it's what's on the other end of the snake that's more interesting.

They select a good hiding place and then wait for prey to come by.

Even with the perfect location, though, it can take a bit of time for the right meal to

get close enough, so these vipers wag their tails around as a lure to draw their prey in.

And one of these snakes, the Iranian spider-tailed viper,

has arguably the most elaborate tail lure of all.

Most of its grayish brown body blends in almost perfectly

with the gypsum rocks common to its habitat.

But its tail looks just like a spider, and with some careful jiggling back and forth,

But don't worry, it's birds that this spider is after.

The good news is that I, personally, am not ever attracted to a spider on the ground,

so I'm probably not gonna get lured in by this.

These snakes seem to mainly hunt larks, shrikes and warblers,

but have also been known to catch the odd gecko, too;

basically anything that goes for that tempting tail.

But, there are some issues with a lure that is so convincing.

Researchers have found snakes with damaged tails,

presumably because some birds actually bit the “spider”.

It's unclear whether this makes the snakes any worse at luring in prey.

But I bet it doesn't feel too great to have part of your tail bitten off!

Hunting underwater comes with an entirely different set of challenges

than the snakes that we've talked about so far.

Like for example, finding your prey when the water is slow moving or not very clear,