Most of the planet is water, and most of that is dark, cold, and barely seen. Here is some of what lives down there, in the highest resolution I could find.
Every photo here is the full-resolution original. Click or tap any one to zoom all the way in. scroll to dive
Neptune grass · Posidonia oceanica · one clone ~100,000 yrs oldA single seagrass meadow off Ibiza is one continuous clone roughly 100,000 years old, older than our species' cave paintings.Coralline seaweed · CorallinalesThese seaweeds turn themselves to stone, and their pink crusts tell coral and abalone larvae where to settle.Ochre sea stars · Pisaster ochraceusThis is the animal that gave science the term keystone species: pull it off the rock and the whole community collapses.Lined chiton · Tonicella lineataIt rasps food with a tongue capped in magnetite, actual iron ore, a magnet's worth of metal in its mouth.Great Barrier Reef · Flynn Reef, Australia · ~2,900 reefsThe only living structure visible from space, and it isn't one reef but nearly 3,000, built by trillions of polyps over 20,000 years.Mandarinfish · Synchiropus splendidusIt is one of only two animals that make blue with actual blue pigment cells, and it wears no scales, just a foul, toxic mucus.Blue ribbon eel · Rhinomuraena quaesitaEvery electric-blue ribbon eel is male; if it lives long enough it turns yellow and becomes female, flipping both sex and color.Mimic octopus · Thaumoctopus mimicus · copies 15+ animalsIt is the only animal known to impersonate other species at will, shape-shifting to copy sea snakes, lionfish and flatfish as the threat demands.Coconut octopus · Amphioctopus marginatusOne of the only invertebrates to use tools: it hoards coconut and clam shells, then reassembles them into a portable suit of armor.Blue-ringed octopus · Hapalochlaena sp. · venom for 26 adultsSmaller than a golf ball, it carries enough toxin to kill 26 adults in minutes, and there is no antivenom; the blue rings flash a second before it bites.Peacock mantis shrimp · Odontodactylus scyllarus · punch ~23 m/sIts club strikes so fast the water boils into a flash of light and heat, and the blow lands with about 1,500 newtons, enough to crack aquarium glass.Variable neon slug · Nembrotha kubaryanaIt steals toxins from the sea squirts it eats and oozes them as a defensive slime, the same chemicals now studied as anticancer leads.Blue dragon · Glaucus atlanticusThis thumbnail-sized slug eats the Portuguese man o' war and stores its stinging cells, concentrating them so its own sting outdoes the jellyfish it robbed.Porcelain crab in an anemone · Neopetrolisthes maculatusIt doesn't fight for its anemone home, it fishes from it, unfurling feathery nets to strain plankton, and snaps off a limb to escape if grabbed.Portuguese man o' war · Physalia physalisIt looks like one animal but is a colony of four kinds of specialized clones that can't survive alone, sailing as a single fleet on its gas-filled float.Radiolarian · Stylosphaera coronata laevis · single cellRadiolarians build skeletons of pure glass, and when they die their shells rain down and pile into seabed ooze hundreds of metres thick.Diatoms · light micrograph · ~20% of our oxygenDiatoms make about a fifth of the oxygen you breathe, roughly one breath in five, while drifting unseen in sunlit seawater.Diatom shell · Stephanopyxis grunowiiIts pores are spaced so precisely that engineers study diatoms as natural blueprints for photonic crystals and nanoscale filters.
where the sunlight gives out
Into the Dark
Barreleye · Macropinna microstomaThose glowing green orbs are its eyes, aimed straight up through a transparent forehead so fragile it is destroyed the moment the fish is hauled to the surface.Siphonophore · Marrus orthocannaIt is not one animal but a swimming colony of identical clones, each built for one job; some of its relatives grow longer than a blue whale.Swimming sea cucumber · Enypniastes eximiaThis one gave up crawling to swim, and is so transparent you can watch its dinner move through its gut; attacked, it sheds glowing skin onto the predator.Pompeii worm · Alvinella pompejana · tail near 80 CMaybe the most heat-tolerant animal alive: its tail bathes near 80 C inside the chimney while its head sits in 22 C water, a 60-degree gap across one body.Leopard seal · Hydrurga leptonyxOne of the only seals that hunts warm-blooded prey, yet about half its diet is tiny krill, sieved through teeth shaped like interlocking combs.Sperm whales · Physeter macrocephalus · largest brain on EarthThey sleep standing up in the water, in ten-minute naps, the least sleep of any mammal, and carry the largest brain of any animal that has ever lived.Giant manta ray · Mobula birostrisMantas have the largest brain-to-body ratio of any fish and have passed the mirror test for self-recognition, a club otherwise limited to apes, dolphins and elephants.Great white shark · Carcharodon carchariasGreat whites are partly warm-blooded, keeping their muscles up to 14 degrees above the surrounding sea so they can sprint after fast prey in cold water.Green sea turtle · Chelonia mydasSea turtles navigate by Earth's magnetic field like a built-in compass, and females cross whole oceans to nest on the very beach where they hatched decades before.Orca · Orcinus orcaThe ocean's apex predator hunts in cultural tribes: some pods specialize on salmon, some on seals, some on hunting other whales, and pass the recipes down for generations.
the ocean is still mostly unmet
Discovered Just Now
Described October 2024Mystery mollusc · Bathydevius caudactylusRobots filmed this glowing sea slug 157 times over 20 years before anyone could name it: a slug that left the seafloor to swim the midnight zone, catching food in a hood.Described 28 February 2024Tailspot wrasse · Halichoeres sancheziIt slipped past science until 2024 because it changes outfit as it grows: the young, the females and the males look like three completely different fish.Described 8 March 2022Rose-veiled fairy wrasse · Cirrhilabrus finifenmaaIts name means rose in Dhivehi, and it is the first new species ever formally named by a Maldivian scientist, in their own language.Described 18 November 2020Duobrachium comb jelly · Duobrachium sparksaeIt is the first animal ever named as a new species entirely from high-definition video, with no specimen caught; it drifts almost 4 km down like a tethered balloon.Described 9 July 2020E.T. sponge · Advhena magnificaIts name literally means magnificent alien; it looked so much like E.T. phoning home that scientists coined a whole new genus, Advhena, just for it.Described 25 September 2018Aphrodite anthias · Tosanoides aphroditeThe divers who found it were so dazzled they failed to notice a shark circling above them, and named it for Aphrodite, the goddess of beauty.