An interactive descent
The ocean is not one place but a stack of worlds, each with less light than the last. Comb jellies drift through all of them. Scroll down, and go with them — from the sunlit surface to trenches seven kilometres deep.
The warm, bright top layer, where sunlight powers nearly all the ocean's plant life. Here the comb jelly's rainbow shimmer is at its most vivid — because the trick needs daylight to split.
A thumb-sized lobate that swarms coastal surface waters. Voracious, self-fertilising, and the notorious invader that helped collapse the Black Sea anchovy fishery.
Mostly 0 – 200 mA glassy pea trailing two long, sticky tentacles it casts like fishing lines for copepods. Shimmers with diffraction — yet, oddly, can't make its own light.
Surface to ~ 100 mLight thins to a dim blue haze, too weak for photosynthesis. This is where bioluminescence takes over from the rainbow — most comb jellies here can flash a startling blue-green when jostled.
One of the most-filmed deep animals: transparent, with a red gut to hide the glow of prey it has swallowed. Flaps two broad lobes to swim through the blue-black.
~ 600 – 1,600 mA tentacle-less sack that hunts other comb jellies, engulfing prey nearly its own size. Rows of stiff macrocilia line its throat like teeth. Ranges from the surface far into the deep.
0 – 3,000 m+Below a thousand metres not a single photon of sunlight remains. The only light is life's own. In permanent darkness, the diffraction rainbow is meaningless — but the combs still beat, rowing animals through cold black water under mounting pressure.
Deep species are often blood-red or maroon — a colour that vanishes to black where no red light penetrates, the perfect deep-sea camouflage. Many are known only from submersible footage.
1,000 – 4,000 mNear-freezing water and pressure that would crush a submarine. Food is scarce, drifting down as flakes of "marine snow." The comb jellies that make a living here are patient, sparse, and strange — some anchoring to the seabed rather than swimming at all.
Flattened, crawling ctenophores that creep over the bottom like slugs, plus rare tethered forms that hold a spot on the seabed with a stalk and fish the water above for descending scraps.
To ~ 6,000 mThe deepest gashes in the seafloor. Comb jellies have been recorded past seven kilometres down — among the deepest-living of all soft-bodied animals, thriving where the weight of the ocean overhead is almost unimaginable.
Filmed by remotely operated vehicles at extreme depth, some clearly recognisable as new species — yet still unnamed, because their bodies dissolve before they can ever be brought to the surface.
Recorded below 7,000 mBack to the light
From bright shallows to lightless trenches, the same half-billion-year-old body plan drifts through every layer of the sea. Rise back up whenever you like.