1000–4000 m
Bathypelagic zone
No sunlight ever reaches this deep. The only light is produced by the organisms themselves.

Pelican eel
Eurypharynx pelecanoides
Pelican eel
Equipped with an oversized mouth able to stretch to swallow prey far larger than itself, it compensates for poor eyesight with a bioluminescent tail used as a lure.
🌊 500–3000 m
- ⚡ Can swallow prey far larger than itself thanks to an extensible stomach
- ⚡ Has a light organ at the tip of its tail used as a lure

Humpback anglerfish
Melanocetus johnsonii
Humpback anglerfish
Hunts in total darkness using a bioluminescent lure dangling above its mouth, and practises one of the strangest reproductive strategies in the animal kingdom: the tiny male ends up fusing with the female.
🌊 300–1200 m
- ⚡ Fishes with a bioluminescent lure produced by symbiotic bacteria
- ⚡ Extreme sexual parasitism: the male fuses physically and vascularly with the female
Sperm whale
Physeter macrocephalus
Sperm whale
The unwitting hero of the novel Moby-Dick and centuries of sailors' legends of titanic battles against monsters of the deep, the sperm whale does indeed fight real duels with the giant squid, whose sucker scars it often carries on its skin.
🌊 0–2000 m
- ⚡ Often carries sucker scars on its skin left by battles with giant squid
- ⚡ Among the deepest divers of all marine mammals, beyond 2,000 m, on a single breath for over an hour

Humboldt squid
Dosidicus gigas
Humboldt squid
Nicknamed the "red devil" for its shifting colour and aggression during group hunts, it can hunt in shoals of several hundred and communicates by rapidly changing colour.
🌊 0–1200 m
- ⚡ Changes colour in a fraction of a second, probably to coordinate group hunting
- ⚡ Tolerates extremely oxygen-poor zones inaccessible to most of its predators

Vampire squid
Vampyroteuthis infernalis
Vampire squid
Despite its terrifying name, "vampire squid from hell", it is a peaceful creature that doesn't hunt but instead filters organic debris drifting in total darkness.
🌊 600–1200 m
- ⚡ Releases a cloud of bioluminescent mucus instead of ink to escape predators
- ⚡ Can turn its membrane inside out like a cape bristling with false spines

Yeti crab
Kiwa hirsuta
Yeti crab
Discovered only in 2005 near Easter Island, this deep-sea crab literally farms bacteria on its hairy claws to feed on them.
🌊 1500–2500 m
- ⚡ Literally farms bacteria on its own claws to feed on them
- ⚡ Can form extremely dense aggregations, several hundred individuals per square metre

Great white shark
Carcharodon carcharias
Great white shark
An iconic apex predator able to leap clean out of the water to surprise prey, and to cover thousands of kilometres on transoceanic migrations still poorly understood.
🌊 0–1200 m
- ⚡ Can leap entirely out of the water to surprise prey at the surface
- ⚡ Ultra-fine electroreception via hundreds of ampullae of Lorenzini

Dumbo octopus
Grimpoteuthis sp.
Dumbo octopus
The cephalopod observed at the greatest depths ever recorded: it owes its name to its two ear-shaped fins reminiscent of the Disney elephant.
🌊 1000–7000 m
- ⚡ The cephalopod observed at the greatest depths ever recorded, down to about 7,000 m
- ⚡ Swims by flapping two ear-shaped fins, a technique unique among octopuses

Giant Pacific octopus
Enteroctopus dofleini
Giant Pacific octopus
Long feared as the "devilfish" in the legends of Indigenous peoples of the North American Pacific coast, this largest known octopus in the world turns out to be remarkably intelligent, able to open jars and recognise individual humans.
🌊 0–1500 m
- ⚡ Has nine brains, one central and one in each of its eight arms, able to act almost independently
- ⚡ Intelligence documented in the lab: able to open jars and recognise certain individual humans

Frilled shark
Chlamydoselachus anguineus
Frilled shark
Nicknamed the "snake shark" or a living fossil, it has changed very little in 80 million years and resembles a giant eel with 300 needle-like teeth.
🌊 50–1500 m
- ⚡ Considered a living fossil, virtually unchanged for 80 million years
- ⚡ The longest known gestation period of any vertebrate: about 3.5 years

Whale shark
Rhincodon typus
Whale shark
The largest fish in the world, a peaceful filter feeder that can reach the size of a school bus while feeding almost exclusively on plankton.
🌊 0–1900 m
- ⚡ The largest fish in the world, able to exceed 18 metres in length
- ⚡ A spot pattern unique to each individual, like a fingerprint

Goblin shark
Mitsukurina owstoni
Goblin shark
Nicknamed the "alien shark", it projects its jaws out of its head at blinding speed to catch prey — one of the strangest attacks in the animal kingdom.
🌊 100–1300 m
- ⚡ Can project its jaws out of its head in a fraction of a second to catch prey
- ⚡ Detects prey via electrical sensors spread across its long snout

Leatherback turtle
Dermochelys coriacea
Leatherback turtle
The largest sea turtle and the deepest-diving reptile known, able to keep its body warmer than the icy deep water thanks to a unique soft, cartilaginous shell.
🌊 0–1280 m
- ⚡ The deepest-diving reptile known, beyond 1,000 m
- ⚡ Can keep its body warmer than the icy water thanks to a unique vascular system

Giant tube worm
Riftia pachyptila
Giant tube worm
Lacking a mouth, stomach or anus, it lives entirely thanks to symbiotic bacteria that convert the toxic hydrogen sulfide of hydrothermal plumes into energy.
🌊 1500–2500 m
- ⚡ Lives without a mouth or stomach, entirely nourished by internal symbiotic bacteria
- ⚡ Its hemoglobin carries both oxygen and a deadly poison without harm, a unique biochemical feat