Millions of years ago, the Earth was home to some of the most famous creatures to ever live: the dinosaurs. Among these giants was the Stegosaurus, a dinosaur known for the large plates on its back and the sharp spikes on its tail. While we often imagine these dinosaurs as massive beasts, every giant had to start out small. A baby Stegosaurus was a tiny, vulnerable creature in a world filled with huge predators.
When a baby Stegosaurus first hatched from its egg, it was surprisingly small. Scientists estimate that a newborn was about the size of a modern-day house cat. This is hard to believe when you consider that a full-grown adult could grow to be thirty feet long and weigh as much as an elephant! These babies were born from eggs laid in nests on the ground. Paleontologists believe that mother dinosaurs might have stayed nearby to protect their young from danger, although the hatchlings likely had to find their own food soon after birth.
One of the biggest mysteries about baby Stegosauruses involves their famous armor. While adults had two rows of tall, bony plates sticking up from their backs, babies were born with very small, flat bumps. As the dinosaur grew, these bumps slowly transformed into the diamond-shaped plates we recognize today. These plates weren't just for show; they may have helped the dinosaur control its body temperature or made the animal look larger to scare away hungry meat-eaters.
The baby's tail was also different from an adult's. The four sharp spikes at the end of the tail, sometimes called a "thagomizer," were much smaller and softer at birth. As the youngster matured, these spikes became hard and deadly weapons. Life was dangerous in the Jurassic period, so growing up quickly was important. By eating plenty of soft ferns and mosses, a baby Stegosaurus could gain hundreds of pounds a year until it finally became an armored giant of the prehistoric forest.
