Overview
- Workers monitoring a City of Oceanside infrastructure project discovered several limb bones, ribs and fragments roughly 12 feet below ground this month, prompting on-site paleontologists to halt routine work.
- Consulting paleontologist Dr. Joseph El Adli led a multi-day hand excavation to expose the bones, encase multiple specimens in plaster field jackets and transport the blocks to an off-site Carlsbad laboratory for careful cleaning and stabilization.
- Paleontologists date the material to Member C of the Santiago Formation and estimate it is about 40 to 45 million years old, placing it in the Uintan North American Land Mammal Age of the Eocene Epoch.
- Researchers say the bones could belong to a brontothere, a hulking, Y-horned hoofed mammal sometimes called a “thunder beast,” or to an amynodont, a stocky, tusked herbivore nicknamed a “swamp rhino,” but a skull or teeth will be needed for a definitive ID.
- The city is withholding the exact dig site to protect the find; after lab preparation the specimens are expected to enter a museum collection and further study that could reveal more about ancient floodplain ecosystems and prompt additional digs in the area.