1. Scutosaurus was an armored parareptilian that lived 250 million years ago and was 3 meters long.
2. Brontornis, or "terror bird," lived in Argentina during the myocene period and was 1.75 meters tall, but could extend its neck up to 2.8 meters.
3. Gorgosaurus was a close relative of T. rex and possessed distinctive serrated teeth that allowed it to efficiently tear the flesh and bones of large prey.
4. Platybelodon, a close relative of the elephant, had a peculiar "nose-like mouth" and used its lower tusk to scrape tree bark.
5. Quetzalcoatlus was one of the largest flying animals in history. Its average wingspan was 36 feet, its shoulder height was at least 10 feet, and it weighed about 500 pounds.
6. Doedicurus clavichordatus was an extinct giant armadillo that lived in South America. It was 1.5 meters tall and 4 meters long.
7. Paraceratherium was the second largest land mammal in history.
8. Atopodentatus was a 3-meter-long herbivorous marine reptile that lived 247 million years ago.
9. Leptoptilos robustus, or Giant Stoke, was an extinct predatory bird that inhabited the island of Flores. It grew to a height of 1.8 meters, weighed 16 kilograms, and preyed on pygmy hominids.
10. Therizinosaurids, or "leaper lizards," possessed enormous claws, but the purpose of these projections remains unclear.