An 11-year-old girl was walking along the shore of Douglas Lake in eastern Tennessee when she noticed something funny. It looked like a really cool rock, so Ryleigh Taylor picked it up and took it with her, only to later discover that what she had found was a 475-million-year-old fossil of a trilobite, an ancient form of life.

Authorities believe the trilobite, an extinct marine arthropod, likely lived in water in that part of the world many millions of years ago. It is extraordinarily rare for somebody to stumble upon a fossil like this, as trilobites molt as they grow so their skeletons often break into hundreds of pieces.

In this case, however, the trilobite was almost entirely intact. The find has fueled young Ryleigh’s interest in science, and she hopes that she can encourage other children to experience nature, according to a WKRG report.

“Trilobites are a fossil group of extinct marine arachnomorph arthropods that form the class Trilobita,” reads an excerpt from Wikipedia. “Trilobites form one of the earliest known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period (521 million years ago), and they flourished throughout the lower Paleozoic era before beginning a drawn-out decline to extinction when, during the Devonian, all trilobite orders except the Proetids died out. Trilobites disappeared in the mass extinction at the end of the Permian about 252 million years ago. The trilobites were among the most successful of all early animals, roaming the oceans for over 270 million years.”