16‑million-year-old freshwater dolphin fossil discovered in Amazon

Scientists have unearthed a fossil of a freshwater dolphin in the Peruvian Amazon, estimated to be 16 million years old. This discovery sheds light on a prehistoric animal from a time when river dolphins, now critically endangered, thrived in these waters.

The finding was detailed in the well-regarded journal Science Advances, highlighting the significance of this ancient cetacean. The unearthed fossil belonged to a dolphin species that once inhabited the Peruvian segment of the Amazon, showcasing an impressive size range of 9.8 to 11.5 feet in length.

River dolphins, belonging to the cetacean order, are among the rarest and most critically endangered species today.

Interestingly, scientists have found that the closest living relatives of these prehistoric dolphins are the river dolphins from South Asia. Despite not being directly related, the existence of these two groups confirms the diverse past of cetaceans that once populated the globe.

A dedicated team from the University of Zurich named this newly discovered species Pebanista yacuruna, paying homage to the mythological water people of Amazonian lore. This species falls under the Platanistoidea group, prevalently found in oceans between 24 and 16 million years ago, suggesting an oceanic lineage that adapted to freshwater environments.

Conducting paleontological research in the Amazon poses significant challenges, the team notes. Fossil excavation is a race against time, feasible only during the dry season when lowering river levels reveal hidden rocks potentially harboring specimens. If not recovered before the onset of the rainy season, these precious links to our planet's ancient history risk being washed away, lost to the rushing waters.

Through this remarkable discovery, scientists hope to unravel more about the evolutionary journey of cetaceans and the environmental shifts that prompted their transition from sea to river habitats.