Fishes

15Paleozoic

Sharpened jaw plates replaced teeth in this heavily armored apex fish.

16Cenozoic

Its hand-sized teeth belonged to a giant shark specialized in hunting marine mammals.

35Paleozoic

Its spiral tooth whorl worked like a permanent slicing blade inside the lower jaw.

36Paleozoic

Opposing tooth blades projected from its jaws like curved shears.

37Paleozoic

Bones inside its fleshy fins foreshadowed the limb pattern of land vertebrates.

82Paleozoic

A flat-headed fish with a mobile neck and wrist-like fin bones approached the anatomy of early tetrapods.

98Recently extinct

One of the world’s largest freshwater fish migrated the length of the Yangtze.

102Paleozoic

Bony armor enclosed its head and chest while jointed pectoral appendages steadied it on the bottom.

167Paleozoic

A broad head shield enclosed its front half, with forward-set eyes and a flexible tail behind the armored box.

168Paleozoic

This giant lobe-finned predator used fanglike teeth to ambush prey, while its fin skeleton followed a tetrapod-like pattern.

174Mesozoic

This giant bony fish opened a broad mouth and strained plankton through dense gill rakers, much like a whale shark.

208Paleozoic

It lacked jaws and paired fins, but its head and gill region were enclosed within strong armor.

209Paleozoic

Sensory fields beneath a broad crescent-shaped head shield helped it search through turbid bottom water.

211Paleozoic

A flat head with upward-facing eyes and limb-like bones inside its fins brought it close to the earliest tetrapods.

257Paleozoic

Rows of paired ventral spines formed a defensive fence beneath this small early jawed fish.

258Paleozoic

Its body was a flattened shield with upward-facing eyes and a mouth beneath the front edge.

259Paleozoic

An eel-like body, continuous fin and spine behind the head made it unlike any modern shark.

260Paleozoic

A single head spine, forked teeth and continuous dorsal fin defined this freshwater shark.

316Mesozoic

Barbed teeth armed a long rostrum used to sense and sweep through bottom prey.

317Mesozoic

Its huge upturned mouth could swallow fish nearly half its own length.

318Mesozoic

Oversized palatine fangs made a modest fish into a formidable midwater hunter.

319Cenozoic

Schools of herring-like fish were sealed into fine lake sediments.

320Paleozoic

An embryo with an umbilical connection records some of the earliest live birth.

321Paleozoic

This giant placoderm lacked sharp jaw blades and may have filtered plankton.

322Mesozoic

Broad crushing teeth paved its mouth for ammonites and shellfish.

437Paleozoic

Placoderm armor enclosed jaw-margin bones resembling those of later bony fish.

438Paleozoic

Huge conical teeth armed a multi-meter freshwater lobe-finned predator.

439Mesozoic

A needle-like snout and slender body converged on modern barracudas.

440Mesozoic

Dorsal fin spines and two tooth shapes handled fish and hard-shelled prey.

441Paleozoic

Males carried a denticle-covered anvil-shaped structure on the back.

442Mesozoic

A giant bony fish filtered plankton near the ocean surface.

488Paleozoic

A broad flat placoderm independently converged on the body shape of a ray.

489Paleozoic

Crescent-shaped lateral horns widened the head armor of a small bottom-dwelling placoderm.

519Paleozoic

Males carried a striking anvil-shaped brush-and-spine complex on the back.

520Paleozoic

A short snout, large eyes and pectoral structures belonged to an early chimaera relative.

521Paleozoic

High-set broad pectoral fins made this miniature holocephalan look winged underwater.

522Paleozoic

A spear-like rostrum and lateral horns projected from this jawless armored fish.

523Paleozoic

A streamlined shield extended into a pointed snout and carried a stabilizing dorsal rise.

524Paleozoic

A long rostrum, side horns and paired openings belonged to an endemic jawless armored lineage.

557Paleozoic

A pair of curved lower-jaw tusks and a kinetic skull helped this lobe-finned fish restrain prey.

558Paleozoic

A streamlined head shield extended into a rostrum, while a dorsal spine and lateral horns stabilized the jawless fish.

559Paleozoic

Tiny rhomboid scales, a deeply forked tail and broad gape marked an early ray-finned fish radiation.