570 vanished lives

289Mesozoic

Only a few million years after the great extinction, ichthyosaurs had already reached whale-like scale.

290Mesozoic

A reduced shell and giant front flippers made it one of the largest Cretaceous sea turtles.

291Cenozoic

Long hind legs and a balancing tail powered a distinctive hopping gait through the forest floor.

292Cenozoic

This giant flightless bird had a massive beak, but evidence favors a mainly herbivorous diet.

293Cenozoic

Hoof-like toes and a large predatory skull belonged to a carnivorous mammal with no modern equivalent.

294Cenozoic

Its body still walked on land, while a distinctive ear region identified it as an early whale.

295Cenozoic

A streamlined whale body still carried tiny external hind limbs with no walking function.

296Cenozoic

A broad hollow nasal ram rose from the skull of this immense brontothere.

297Cenozoic

A forked Y-shaped nasal horn joined two brow horns in the most elaborate protoceratid display.

298Cenozoic

Short legs and a barrel body gave this grazing rhinoceros a hippo-like outline.

299Cenozoic

Thick hide reinforced by tiny bony nodules protected this large ground sloth.

300Cenozoic

Huge curved claws belonged to a forest browser whose name is tied to Thomas Jefferson.

301Precambrian

Its quilted branches lay flat rather than rising from a stem.

302Precambrian

Dense stands of narrow tubes formed one of the earliest large colonial scenes.

303Precambrian

Bead-like discs arranged in strings may record an early macroscopic colony.

304Precambrian

Centimeter-wide ribbons curled into regular spirals among the earliest macroscopic fossils.

305Precambrian

Cell division and branching resemble living red algae and may record early sexual reproduction.

306Paleozoic

Branching microscopic hyphae show fungi helping to build the earliest soils.

307Precambrian

Branching spherical microfossils may push the fungal record toward one billion years.

308Paleozoic

A flower-bud body carried five feeding and respiratory grooves.

309Paleozoic

Radiating septa inside a horn-shaped skeleton resemble a stone sun.

310Paleozoic

Linked tubes formed honeycomb chains across Paleozoic reefs.

311Paleozoic

Fine radial ribs covered rounded shells that once crowded ancient seabeds.

312Paleozoic

A broad hinge line formed stone wings that stabilized the shell on soft mud.