- University of Zurich paleontologists discovered a new species of freshwater dolphin in the Peruvian Amazon region.
- This 16-million-year-old species, called Pebanista yacuruna, is the largest river dolphin ever found and is closely related to South Asian river dolphins.
- This discovery sheds light on the evolutionary history of river dolphins, showing how marine dolphins living in ancient Amazonia adapted to freshwater ecosystems.
Paleontologists from the University of Zurich have uncovered a new species of freshwater dolphin, Pebanista yacuruna, in the Peruvian Amazon. This species, which dates back 16 million years, is the largest river dolphin ever found, measuring between 3 and 3.5 meters in length. Unlike these dolphins’ living Amazonian relatives, Pebanista’s closest living relatives are the South Asian river dolphins.
This discovery sheds light on the evolutionary history of river dolphins and suggests that Pebanista’s ancestors were marine dolphins that invaded freshwater ecosystems in the ancient Amazon. These ancient dolphins thrived in a landscape dominated by lakes and swamps called Pebas, which covered much of modern-day Amazonia, but as these ecosystems transitioned into modern Amazonia about 10 million years ago, the Pebanista’s prey disappeared, leading to extinction. This ecological gap was later filled by the ancestors of today’s Amazon river dolphins.
The fossil record also reveals that Pebanista, like its modern relatives, relied heavily on echolocation to hunt in the muddy waters where it lived. The discovery highlights the difficulties of paleontological fieldwork in the Amazon, where fossils are only accessible during the dry season.
The holotype of Pebanista was found in 2018 by an expedition led by Peruvian paleontologist Rodolfo Salas-Gismondi, and the specimen is now housed at the Museo de Historia Natural in Lima. This discovery underlines the importance of continued exploration and research in uncovering the rich paleontological history of the Amazon region.
Compiled by: Eliz Canyurt