Hey.
I'm Ben Bowlin.
And I'm Jonathan Strickland.
Today's question is, how do shark senses work?
Under water.
See ya.
But wait-- Come on, man.
What are you doing?
Do I need to be more specific?
Yeah.
All right.
Fine.
One of the main reasons sharks are such effective predators
is their keenly attuned senses.
Yeah.
It's not just the nose, right?
They actually have several acute senses,
but these must all work together to make
a shark a decent hunter.
I like the nose, though, Jon.
Let's start with the nose.
All right.
As the shark moves, water flows through two
forward-facing nostrils positioned
along the sides of the snout.
The water enters the nasal passage,
moves past folds of skin covered with sensory cells.
Right.
Now in some sharks, these sensitive cells
can detect even the slightest traces of blood in the water.
So a great white shark, for example,
would be able to detect a single drop of blood
in, well, an Olympic-sized swimming pool.
Though you don't normally find great whites
in Olympic-sized swimming pools.
It's a creepy metric to use.
It is, yeah.
Most sharks can detect blood and animal odors for miles.
Uh, or kilometers.
1.6 kilometers to a mile, you know.
Yeah.
Oh, yeah.
And a shark's sense of smell is also
unique in that it's directional.
Say what?
Right.
OK.
So twin nasal cavities, right?
OK.
In the way that you have two ears.
Yeah.
The smell would be coming from the left of the shark.
It will arrive in that left nasal cavity
before it hits the right one.
So in this way, a shark can figure out
where a smell is coming from.
You know, sharks also have a very.
Acute sense of hearing research suggests
they can hear low-pitched sounds well
below the range of human hearing.
Now sharks may track sounds over many kilometers or--
Miles.
Mm hmm.
For distress.
They're listening for distress sounds from wounded prey.
[HIGH-PITCHED_VOICE] Help me.
I'm dying.
I can't swim.
I'm bleeding a lot.
Yeah.
That would be exactly what they're listening for.
What about eyesight?
[NORMAL VOICE] Oh, eyesight's a really good one,
because eyesight varies from shark to shark,
or at least species to species.
So some of the less active sharks
that stay near the water's surface,
they don't have particularly acute eyesight.
However, sharks that stay at the bottom of the ocean--
Now these sharks have evolved to have very large eyes that
let them see in near total darkness.
Most all sharks have a pretty wide field of view
because their eyes are positioned
on each side of their head.
Cut that out.
OK.
Right.
But they also rely on their sense of taste, right?
Oh, yes.
Yes.
Because sharks are kind of picky, actually.
They'll give something a test bite
before they fully commit to eating it.
That reminds me of something that
happened between me and Josh Clark just five minutes ago.
Anyway, these sensitive taste buds
are clustered in the mouth.
They analyze the potential meal to see if it's palatable.
Right.
They'll often reject prey that's outside of their ordinary diet.
So a human being, not normally on a shark's diet,
so sometimes they just reject it immediately.
Or a tire--
Yeah.
--a license plate.
A car.
Right, yeah.
Like a whole car.
These sort of things sharks don't usually
put that on the menu.
But they also possess some senses
we don't fully understand, right?
Yeah.
Like the ampullae of Lorenzini.
Oh, man.
I loved him in that one Italian zombie flick.
That was intense.
It's uh-- It's an organ that gives sharks the ability
to do something called electoreception.
I was totally thinking of something else.
The ampullae consists of small clusters
of electrically-sensitive receptor cells positioned
under the skin in the shark's head.
Right.
They're connected to pores on the skin's surface
via small jelly-filled tubes.
Now we don't fully understand everything
about these ampullary organs, but we
know that the sensors allow sharks
to see weak electrical fields generated by living organisms.
So the range of electrosense seems to be,
well, fairly limited.
But I say it still counts as a superpower.
Oh, fair enough.
Fair enough.
I'll allow it.
Then we'll continue to another unique sense
organ, the shark's lateral line.
Right.
It's basically a set of tubes just under the shark's skin.
So you've got these two main tubes
running on both sides of the body from the head
all the way down to the tail.
Water flows through these main tubes
through pores on the skin's surface.
The inside of the main tubes are lined
with hair-like protrusions, which
are connected to sensory cells.
When something comes near the shark,
the water running through the lateral line
moves back and forth.
This stimulates the sensory cells,
alerting the shark to any potential prey or predators
in the area.
The combination of all of these senses we've talked about
make a shark an incomparable predator.
So the success of sharks is due largely
to those physiological advancements which
have kind of happened over the course of millions of years
to create an eating machine.
His eyes are like a doll's eyes.
And when it bites, they roll back.
That's it.
Sharks are superbly built to find food.
Their senses work in unison.
That Jaws excerpt was for free.
Yes.
Let me tell you about the time I was on The Indianapolis.
That's actually for later.
In the meantime, if you enjoyed this video make sure
you like it and subscribe to the channel.
We've got a lot more information coming your way,
not just about sharks, about other stuff.
Yeah.
We have the big board over there.
That one's good.
Yeah, that one's good.
These are all actually good.
I like all of these.
Man, Robert called that one?
Awww.
Yeah.