How Dinosaurs Rose and Fell

Dinosaurs ruled Earth for 160 million years, but most people don't know they

started smaller than a golden retriever. More than 250 million years ago, the Permian Mass

Extinction wiped out ninety percent of all life on Earth. Oceans emptied, forests burned,

and the planet became almost lifeless. But small reptile ancestors called archosaurs survived

because they had stronger legs, upright posture, and could move faster than anything else.

Around 230 million years ago, the first true dinosaurs appeared with efficient breathing systems

and endless stamina that let them outrun and outlast every competitor. They weren't rulers

at first, living in shadows of larger predators, but climate shifts and volcanic eruptions