Hello and welcome to another episode of From the Vault, the podcast, where we dive deep into the Squiz Kids archives and dust off an old favourite for a re-listen.
And speaking of diving deep, that's literally what I've just done to dig out this week's episode.
Seems we've had of a water pipe leak in the archive basement here at Squiz Kids HQ and I needed a snorkel and a pair of goggles to locate this week's episode.
But what an episode it is.
Have you ever stared out across the ocean and wondered what lurks beneath?
Not just beneath the surface, mind you, because we all know what's there.
Sharks and fish and whales and coral and seaweed.
I mean in the deepest, darkest depths of the ocean.
Well, you're about to join us on an adventure to the deep, where the weirdest creatures on planet Earth live, including the fish that live so far down that the pressure of all the water above it is like having 1000 elephants standing on top of you.
I mean, can you even imagine?
And this fish just swims around down there like it's no biggie.
Settle in.
Whack on your deep sea diving suit and let's get down kids way, way down in this Squiz Kids shortcut to the deep sea.
Enjoy.
This is a Squiz Kids podcast.
Your fresh take on what's happening in the world around you.
Welcome to a place with three-legged fish, snow and animals that glow in the dark.
This is your squeeze kids shortcut to the deep sea, the podcast where we dive into the who what when where, why and how of the big news stories.
I'm amanda bauer and i'm bryce corbett.
In this special shortcut, we'll take you through how deep the deep sea really is, what lives there, why bioluminescence is so important.
Listen carefully.
There's a quiz at the end.
How?
Bryce, when I think of the ocean, my first thought is of the beach.
And when I go swimming in the ocean, I'm in what's called the sunlight zone or, more scientifically, the epipelagic zone.
So that goes from the water's surface to 200 metres down.
What?
200 metres?
That's two NRL fields from tri-line to tri-line.
Imagine diving down that deep.
Yeah, the Sunlight Zone already goes pretty deep.
It contains dolphins, a favourite schools of fish sharks, and lots of plankton, which makes its own food from the sun.
So what would you see if you went down further than that?
Alright, so the next zone is called the Twilight Zone. or the mesopelagic zone.
It covers the area that is between 200 metres and 1,000 metres below the surface.
Wow.
So this area receives only faint filtered sunlight, which means that no organisms that use photosynthesis remember, that's where you make your own food from the sunlight none of them can survive.
Okay.
The animals that do live there often have large ovaries so they can see better in the near darkness.
So is that the deep sea?
We still haven't reached the deep sea.
What?
We've only gone down through about one quarter of the ocean's depths.
Wow.
The remaining three quarters are cold, permanently dark and sometimes called the midnight zone.
Wow.
The deep sea is more than 1000 metres deep deep 1000 meters.
I'm trying to imagine diving the length of 10 nrl fields.
Well, that would be very dangerous, actually deadly, and not just because you obviously couldn't hold your breath for that long.
The pressure of that much water on top of you would cause your body to just stop working properly Wow.
So special equipment is needed to explore the deepest parts of the ocean.
So tell me, Amanda, what have they found?
What?
Well, the first thing they found Bryce, is that the deep sea has three different levels, each with its own kinds of creatures living in it.
So the first goes from 1,000 metres deep to 3,000 metres and it's called the bathypelagic zone.
The water is about 4 degrees Celsius and many of the creatures that live there eat snow.
Eat snow?
Well, technically it's called marine snow.
It's little flakes of dead and decomposing animals silt, poo and other organic items that have washed into the sea from land.
Those flakes really do look quite a bit like snow falling through the water.
Wow!
So tell me, what eats marine snow?
Well, animals that don't need a lot of food because those flakes are pretty small and that process food slowly.
Those creatures usually have squishy bodies and slimy skin.
I'll put a link in your episode notes to two videos.
The first is of the black hagfish, which has a skull but no spine.
Wow.
And it has holes along the side of its body, some for breathing and some for sliming.
Ew.
When it eats, its mouth truly makes it look like a creature from the Star Wars cantina.
Ha ha!
And then there's the amazing Gulper Eel, which has this ginormous expandable gullet that balloons out when it's feeling threat.
Whoa, amazing.
So what do we find if we go even deeper?
Well, between 4,000 and 6,000 metres deep, we're in the Abyssal Pelagic Zone.
The pressure here is 600 times greater than at sea level.
So most of those creatures we saw on the way down in the sunlight and twilight zones definitely couldn't survive here.
The incredible tripod fish is one of the ocean's deepest living fish species.
Tripod?
Hmm, I only know that word from a camera tripod, those three legs that hold a camera stable at a particular height.
Yeah, and that is pretty much what a tripod fish does.
It's only about 30 centimetres long, so the length of a ruler.
Yeah.
But it has three long bony fins that extend out for a metre.
Oh, wow.
Researchers think that they fill with water when the tripod fish wants to stand on the deep ocean floor.
And why on earth would they want to stand on the deep ocean floor?
Well, the food that the tripod fish eat is carried by a current.
And if you're right on the ocean floor, there's not a lot of current.
So those tripod fins hold its body at a level where the current literally brings the food to them.
They can just open their mouths and eat.
How convenient!
That is right.
The final level is the deepest of the deep.
From 6000 metres below sea level all the way down to the deepest part of the ocean, which is the Mariana Trench at 10994 metres.
That's just six metres away from 11 kilometres from the top of the ocean down.
Unbelievable.
So not much is known about what lives down there.
But in 2018, scientists officially declared a new species of fish the deepest ever found.
Right.
It's a type of snailfish.
And get this, Bryce, it's about 30 centimetres long, again, like a ruler.
But it can handle water pressure that is the equivalent of 1,600 elephants standing on its head.
Wow.
Wow, that is incredible.
Bryce.
There are so many more incredible things about the deep sea, like super salty lakes that are at the bottom of the ocean.
Wow.
Hydrothermal vents where scalding water spews out of cracks in the Earth's crust.
There are deep sea reefs.
Animals that produce their own light in the pitch black water.
Unbelievable.
Amanda, I wish this podcast could go for an hour so we could talk about all of those things, but I'm especially intrigued by bioluminescent animals.
Bioluminescent, of course, means that they produce their own light.
Why is that so important in the deep sea?
Isn't it being able to make yourself glow in the dark for sure?
Video footage from the deep sea actually looks a bit like a starry sky.
There are so many animals lighting themselves up and then turning themselves off.
Wow, now many have evolved to have this ability to help them catch food.
My favourite is probably the deep sea anglerfish, because it has this glowing lure that truly looks like a fishing rod.
Yeah.
And it bobs back and forth on the top of its head to attract prey.
Amazing.
So once they see that and come to take a bite, it opens its enormous jaws and chomp.
Yeah.
Whoa.
And I'm guessing another reason to glow in the dark is to attract a boyfriend or girlfriend, the same way that land animals do flashy things, like a peacock spreading its colourful feathers.
That's exactly right.
And some also do it to scare other creatures off.
So a sudden burst of light might scare or distract a predator enough so that you can swim away and avoid becoming its dinner.
I'll put a link in your episode notes to a video from none other than Sir David Attenborough that shows some examples of the different bioluminescent creatures in the deep sea.
Now, some of them have never been caught, studied or identified.
That is amazing.
The deep sea, it's a mysterious place.
Time for the quiz.
This is the part of the podcast where you get to test how well you've been listening.
Question number one.
Many deep sea creatures eat flakes of food called what?
Yeah, that's right.
Good listening ears.
It's marine snow.
Question number two.
What's the name of the fish that has three long fins to help it stand?
Yep, it's the tripod fish.
Question number three.
What's one reason that bioluminescence is important to deep sea creatures?
That's right.
They use it to get food, to find a mate or to protect themselves.
That's all we have time for today.
Thanks for joining us as we explored the who, what, how, where, when and why of the deep sea.
Now get out there and have a most excellent day.
