Tyrannosaurus rex dominated the tail end of the dinosaur age. A recent surge in discoveries has revolutionized our understanding of the fierce carnivore. This is one of four dynamic designs that depict the awe-inspiring dinosaur in growth stages from infancy to adulthood.

One design illustrates a face-to-face encounter with a T. rex approaching through a forest clearing; another shows the same young adult T. rex with a young Triceratops — both dinosaurs shown in fossil form.

The third and fourth stamps depict a newly hatched T. rex covered with downy feathers and a bare-skinned juvenile T. rex chasing a primitive mammal.

“The Nation’s T. rex,” the young adult depicted on two of the stamps, was discovered on federal land in Montana and is one of the most studied and important specimens ever found. Its remains are now exhibited at the Smithsonian Institution’s National Museum of Natural History in Washington, DC.

Tyrannosaurus Rex, also known and colloquially as T. rex, was a large carnivorous theropod dinosaur that lived from 68 to 66 million years ago. Tyrannosaurus is the most well known and most iconic prehistoric animal that has ever lived. Its fossil remains are relatively rare, as of 2012 only 44 specimens had been found, including three complete skulls. The most complete specimen of Tyrannosaurus rex; Sue; measures about 12.3 meters (40 feet) long, stands 3.66 meters (12 feet) tall at hips and weighed about 8.4 tons (9.3 short tons) or more, thought the newest specimen called Scotty indicates tyrannosaurus could be capable of reaching 13m (43ft) in size; meaning this specimen was larger than the weight of the average African Bush Elephant and nearly as large as the largest bull African Bush Elephant and it was also taller, longer and faster than elephants who can run as fast as a human. It was the largest and most powerful land carnivore ever found in North America.