Data Deficient

Gastornis

Eocene giant with a powerhouse beak

Thylacosmilus

The saber-tooth that wasn't a cat

Andrewsarchus

Big skull, bigger mystery

Dinocrocuta

Not a hyena-just built like one.

Elephant Bird

Madagascar's lost giants of the egg

Black Throat Monitor

Dark throat. Big brain. Savanna hunter.

Angled Sunbeam Caterpillar

Small larva, big ant allies

Leichhardt's Grasshopper

Northern Australia's warning-coloured hopper

Sehuencas Water Frog

Bolivia's stream sentinel

Stoplight Loosejaw

The deep sea's red-light hunter

Kaua'i ‘Ō‘ō

The vanished voice of Kauai

Dimetrodon

Permian sailback-before dinosaurs

Eryops

Permian powerhouse of the ponds

Deinocheirus

The terrible-handed wetland omnivore

Haikouichthys

A tiny fossil at vertebrates' dawn

Quetzalcoatlus northropi

Largest skies, long-necked hunter

Ornithocheirus

Bird-hand ruler of Cretaceous skies

Allosaurus

Jurassic hunter of the Morrison

Vegavis

A polar clue to waterfowl origins

Scutosaurus

Permian armor, plant-powered

Wiwaxia

Spiny armor from the Cambrian seafloor

Palaeoloxodon namadicus

The giant straight-tusked titan of Ice-Age India

Barylambda

Heavyweight of the Paleocene

Dunkleosteus

Armor-plated apex of Devonian seas