---
title: "The gentoo penguin is actually four penguins, and three of them have a problem"
description: "Whole genomes from 64 birds settle a century of argument, name the first new penguin species since 1921 — and hand out the climate risk unevenly"
author: "Nate Ledger"
published: 2026-09-27T00:00:00Z
modified: 2026-09-27T09:07:45Z
url: https://rews.cc/a/the-gentoo-penguin-is-actually-four-penguins-and-three-of-th-779c02
language: en
tags: ["penguins", "climate", "genomics", "conservation", "antarctica", "science"]
publisher: "Rews (https://rews.cc)"
---

# The gentoo penguin is actually four penguins, and three of them have a problem

*Whole genomes from 64 birds settle a century of argument, name the first new penguin species since 1921 — and hand out the climate risk unevenly*

By Nate Ledger · September 27, 2026 · https://rews.cc/a/the-gentoo-penguin-is-actually-four-penguins-and-three-of-th-779c02

## In brief

- Genomic study finds the gentoo penguin is four distinct species, one previously unknown to science
- Pygoscelis kerguelensis, from the Kerguelen Islands, is the first new penguin species described since 1921
- Three sub-Antarctic island species could find their homes uninhabitable by 2050 under a moderate warming scenario
- Generalist diets kept gentoos near their colonies, driving isolation and speciation over 300,000–500,000 years
- Each species carries distinct gene adaptations; the data may also aid avian influenza research

Here is a pleasant accounting problem from the Southern Ocean. For more than a century, science maintained a ledger with one entry on it — the gentoo penguin, *Pygoscelis papua*, a single species spread across a vast range from the Falkland Islands to the Antarctic Peninsula. A team led by researchers at UC Berkeley and several Chilean institutions has now audited that ledger using whole genome sequences from 64 individuals across 10 breeding colonies, and concluded the entry should really be four. One of the four, *Pygoscelis kerguelensis*, from the Kerguelen Islands in the southern Indian Ocean, is entirely new to science — the first newly described penguin species since the northern rockhopper got its name in 1921. The findings were published in *Communications Biology* in April 2026.

The four-way split works like this, according to the researchers. The new species, *P. kerguelensis*, lives on what are also called the Desolation Islands, 450km from the nearest land, looking virtually identical to any other gentoo but differing slightly in size and vocalisation — and clearly differing in its DNA. The other three are previously recognised subspecies now promoted to full species: an eastern lineage, *Pygoscelis taeniata*, on the Crozet, Marion and Macquarie Islands; a northern lineage, which keeps the name *Pygoscelis papua*, confined to the Falkland/Malvinas and Martillo Islands; and the most numerous of the lot, the southern lineage *Pygoscelis ellsworthi*, on the Antarctic Peninsula, coastal Antarctica and South Georgia.

What makes this more than taxonomic housekeeping is that splitting one species into four is also a redistribution of risk. When there was one gentoo with a giant range, climate change was, on paper, one species’ shared problem. Now the exposure can be allocated properly, and it turns out to be allocated badly. Using climate prediction models, the team found that under a moderate warming scenario, all three island-dwelling sub-Antarctic species will find their current homes uninhabitable by 2050 — with few or no suitable islands nearby to move to. Only the southern gentoo, the one that actually lives in Antarctica, is predicted to be minimally affected, and might even benefit from an expanded range.

> In Antarctica, of course, other species, not the gentoo, are threatened by climate change. But the gentoo is of most concern in the sub-Antarctic region.

That was Juliana Vianna of Andrés Bello National University in Santiago, one of the paper’s senior authors. The sub-Antarctic is an awkward place to mount a conservation effort: a scatter of wildly separated islands governed by, among others, Chile, South Africa, France, the Netherlands, Australia and New Zealand. “It’s very important that conservation institutions in all the different countries involved recognise and take appropriate action to save these three gentoo penguin species,” Vianna said. She compared the gentoos’ predicament to Galapagos penguins and other island endemics: “Those islands are very isolated, and these penguins cannot adapt easily to colonise any other region.”

The reason the gentoo fractured into four species in the first place is, in essence, a lifestyle choice. Gentoos are the opposite of picky eaters — they’ll take fish, krill, squid or cuttlefish, essentially anything they can chase down. That generalist diet is a competitive advantage over fussier penguins like emperors and Adélies, but it has a side effect: a bird that is happy with whatever is in front of it has no reason to roam. Gentoos stay near their breeding colonies and nest in the same spot year after year, so populations drift into isolation and accumulate local adaptations. Add the Antarctic Polar Front — a temperature and salinity barrier in the Southern Ocean that animals mostly don’t cross — and over the past 300,000 to 500,000 years, one penguin quietly became four.

The genomic analysis, led by University of Chile graduate student Daly Noll, reads those adaptations directly off the DNA. The southern gentoo carries more genes tied to heat generation, fat and lipid storage and light perception — the toolkit of a bird that winters in Antarctica. The eastern gentoo is enriched for genes supporting energy-efficient carbohydrate metabolism and enhanced diving capacity, suited to long underwater work in low-productivity seas. The northern gentoo shows enrichment for sustained foraging: digestion pathways, plus cardiac contraction and muscle excitation. Same silhouette, four different operating manuals.

The debate itself has a pedigree. “There’s probably no species of penguin where the taxonomy has been more debated than the gentoo penguin,” said Rauri Bowie, a UC Berkeley professor and curator in the Museum of Vertebrate Zoology. “For over 100 years, it’s been controversial as to how many species or how many subspecies there are. What this paper does is try to address that question using cutting-edge integrative approaches.” It is the first gentoo study to span nearly the bird’s entire geographical range, and the researchers note the trove of genomic data will have a second life in work on avian influenza, which is currently hammering bird and mammal populations worldwide.

There is a small irony worth sitting with. The trait that made the gentoo a survivor — eat anything, adapt locally, thrive where fussier penguins starve — is also the trait that stranded three of its four species on remote islands just as those islands began to warm. The one lineage that stayed flexible enough to live in the coldest place on Earth is the one best placed for a hotter one. Conservation status, it turns out, is partly a question of where you happened to settle down 300,000 years ago.