(Intro music)
Bioluminescence is definitely one of the coolest things in nature
And I'm not disparaging any of the other wonders of the natural world
But the just the emission of light by a living thing, it's so cool!
And although there are lots of bioluminescent organisms in the world
From angler fish, to fungi, to comb jellies, one of the coolest places to see bioluminescence in action
is in the Waitomo caves on New Zealand's, North Island. The caves are pretty normal, as caves go.
Until you get down in there, and you realize the walls and the ceiling are glowing blue!
And you feel kind of like they shouldn't be, but they are, right?
Like, is anybody else on this cave boat think that the cave walls are glowing?!
Well, probably wouldn't happen exactly that way. Cause you probably wouldn't be down there if you didn't already know
About the glowing thing before you got there.
But they might not have told you the coolest part: Why the cave is glowing?
Turns out it has to do with the New Zealand fungus gnat Arachnocampa Luminosa
Which is actually not very interesting in its adult stage
But as larvae they light up the Waitomo caves
Like Pink Floyd night at the planetarium.
Before their very short mouthless lives as an adult mosquito-sized gnat
A. Luminosa spends months as Carnivorous Larvae commonly known as glow worms.
These larvae can get about as long as a match and are pretty boring looking in the light of day.
But in the dark a blueish green light glows through their transparent skin.
Their bioluminescence is a product of a chemical reaction in a special organ in their butts
Where oxygen, adenosine triphosphate, and a waste product called luciferin, combine to make light.
This bioluminescence is used to attract food and mates.
The glow worms can live between 6 and 12 months on the walls of caves or other sheltered areas, usually over water.
And the reason that they live in such dark precarious places, is that the New Zealand fungus gnat larvae are great hunters.
They hang out on the cave ceiling in the dark and suspend a fishing line made of silk covered with globs of sticky mucus
They use their bioluminescence to attract insects to their traps and then, bam!
The prey gets all tangled up in their goopy lines
And they reel them in, paralyze 'em, and gobble 'em up.
Since the adults don't have mouths the larvae have to eat enough to keep the adult alive during mating.
So they'll eat pretty much whatever wanders into their net, even other glowworms.
It's this cutthroat cannibalistic struggle for survival that makes the Waitomo Caves, so beautiful to visit.
Ain't that always the way.
Thank you for watching this episode of Scishow.
If you have any questions comments or suggestions for other weird places we should talk about
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(Outro music)
