The Remarkable Backstory of a 475-Million-Year-Old Fossil

Monday, May 7, 2018

The 475-million-year-old fossil

The discovery of a 475-million-year-old trilobite exoskeleton in Tennessee recently is a glimpse into an ancient past.

An 11-year-old girl in Tennessee made an extraordinary find recently, discovering a 475-million-year-old fossil of an empty cast exoskeleton from an ancient creature known as a trilobite, as we reported recently. And it reveals the stunning reality of what our planet looked like long before the existence of mankind, when creatures such as the trilobite thrived in the seas.

The intact trilobite exoskeleton, an extraordinarily rare find since such exoskeletons typically shatter into many pieces, was found on the shore of Douglas Lake in East Tennessee by Ryleigh Taylor. This marine arthropod has long since gone extinct, but hundreds of millions of years ago it lived right here in the United States, albeit when it was covered in water.

The trilobite is an extraordinary creature, first appearing in the early Cambrian period some 521 million years ago. There are an estimated 17,000 known species, and the study of these creatures have led to breakthroughs in everything from evolutionary biology to plate tectonics.

Trilobites are typically quite small, but not always. The largest one ever found was Isotelus rex in Manitoba, which measured 28 inches in length and 16 inches and width.

Today, you can find trilobite fossils all around the world, owing to the tremendous amount of species that have lived in the history of the Earth (although the discovery of an intact exoskeleton is quite rare).

Long before humans, these creatures populated the Earth, making it a very different place than we know of today. It is a chilling reminder of just how short of a time we have spent on this Earth as a species, and how different our planet looked eons ago.

Trilobites are a fossil group of extinct marine arachnomorph arthropods that form the class Trilobita,” reads a Wikipedia excerpt. “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.”