PEBANISTA YACURUNA (Syllabus: GS Paper 3 – Env and Eco)

Context: Paleontologists from the University of Zurich have announced the discovery of a new species of freshwater dolphin in the Peruvian Amazon region.

Discovery of the Largest River Dolphin

• New Species Discovered: The newly discovered species is named Pebanista yacuruna after a mythical aquatic people of the Amazon basin.
• Age of the Species: Pebanista yacuruna, found in Peruvian Amazonia, is estimated to be 16 million years old.
• Length: Between 3 and 3.5 meters.
• IUCN Red List Conservation status: Endangered
• Ancestors of Platanistoidea: The species belongs to the Platanistoidea, a group of dolphins prevalent in the world's oceans 24 to 16 million years ago.
• Invasion of Freshwater Ecosystems: Researchers propose that the marine ancestors of Platanistoidea adapted to the prey-rich freshwater ecosystems of proto-Amazonia.
• Pebas Landscape: Ancient Amazonia was characterized by a vast system of lakes and swamps known as Pebas, covering areas in Colombia, Ecuador, Bolivia, Peru, and Brazil.
• Variety of Habitats: The Pebas landscape included aquatic, semi-aquatic, and terrestrial ecosystems, such as swamps and floodplains.

River Dolphins

• About: River dolphins stand out as some of the rarest modern cetaceans, facing critical endangerment across most extant species.
• Diverse Lineage: Despite their shared aquatic habitat and similar appearances, river dolphins are not directly related, but instead, they are the last survivors of distinct cetacean groups.
• Late Survivors: These unique creatures represent the remnants of various cetacean lineages that once thrived on our planet, underscoring their evolutionary significance amidst modern endangerment.
• Polyphyletic Nature: River dolphins form a polyphyletic group of fully aquatic mammals residing exclusively in freshwater or brackish water.