“Until recently, the gentoo penguin (aka Pygoscelis papua) was thought to be a single species spread across several areas. However a team of penguin experts led by scientists from University of California, UC Berkeley, and several institutions from Chile recently studied their genes and confirmed the gentoo is actually four separate species.

Gentoos tend to stick close to their breeding colonies, returning to the same nesting sites year after year. Over time, this meant different populations became isolated and adapted to their local environments, eventually evolving into separate species. The Eastern gentoo (Pygoscelis taeniata) lives on the Crozet, Marion, and Macquarie Islands, while the Northern gentoo (Pygoscelis papua) is found around the Falkland and Martillo Islands. The Southern gentoo (Pygoscelis ellsworthi) has the largest population and inhabits the Antarctic Peninsula, coastal Antarctica, and South Georgia.

The fourth and newly recognized, southeastern gentoo (Pygoscelis kerguelensis) lives on the remote Kerguelen Islands in the southern Indian Ocean, around 450 kilometers (279 miles) from the nearest land. It looks similar to other gentoo penguins but is genetically distinct enough to be recognized as a separate species. Its distinct size and vocalizations are further clues that set it apart.”

From My Modern Met.