With their small brains and enormous bodies, these creatures have long been the poster children for animals destined to go extinct. But recent discoveries have completely rewritten the doomed sauropod narrative.

I study a lesser known group of sauropod dinosaurs—the Titanosauria, or "titanic reptiles." Instead of going extinct, titanosaurs flourished long after their more famous cousins vanished. Not only were they large and in charge on all seven continents, they held their own amid the newly evolved duck-billed and horned dinosaurs, until an asteroid struck Earth and ended the age of dinosaurs.

The secret to titanosaurs' remarkable biological success may be how they merged the best of both reptile and mammal characteristics to form a unique way of life.

Moving with the continents

Titanosaurs originated by the Early Cretaceous Period, nearly 126 million years ago, at a time when many of the Earth's landmasses were much closer together than they are today.

Over the next 75 million to 80 million years, the continents slowly separated, and titanosaurs drifted along with the changing formations, becoming distributed worldwide.