A study published on April 23 in the journal Communications Biology describes the discovery of a new penguin species, Pygoscelis kerguelensis, based on genetic analysis of 64 pygoscelid penguins from 10 colonies. The research was led by Chilean biologists and researchers from the University of California, Berkeley. This marks the first new penguin species described since 1921, when the Moseley's crested penguin (Eudyptes moseleyi) was identified. The new species, found on the Kerguelen Islands and likely on the neighboring Heard Island in the southern Indian Ocean, had previously been observed and collected. The reference specimen, an adult male collected on Kerguelen on December 31, 1897, is preserved at the American Museum of Natural History in New York and was previously classified among ordinary pygoscelid penguins. Genetic analyses indicate that pygoscelid penguins form four distinct groups, each constituting a separate species: three former subspecies elevated to species status and one new species. To the east, Pygoscelis taeniata nests on the Crozet, Marion, and Macquarie Islands, with the latter belonging to Australia. To the north, Pygoscelis papua, which retains its historical name, is confined to the Falkland Islands and Martillo Island in South America. To the south, Pygoscelis ellsworthi, the most numerous, lives on the Antarctic Peninsula, the coasts of the continent, and the island of South Georgia. Pygoscelis kerguelensis is distinguished from other species by its genes, size, and call. It is smaller than the Falkland penguin and larger than the Antarctic penguin. At first glance, it resembles any pygoscelid penguin with a black back and white belly. Biologists refer to it as a "cryptic" species. The genomes also show how species adapt to their environment. The Antarctic species carries genes related to heat production, fat storage, and light perception. The eastern species carries more genes for energy conservation and extending dives. Researchers have modeled the favorable habitat of each species in 2050 under a moderate warming scenario. Only the Antarctic species, Pygoscelis ellsworthi, would benefit, with its favorable habitat expanding by about 9%. It could establish itself further inland on the continent, potentially replacing emperor penguins, Adélie penguins, and gentoo penguins, which decline with the ice and krill. For the three subantarctic island species, the models predict the loss of almost all favorable habitat around their current islands, with few or no nearby islands to retreat to. Only the areas around Heard Island would remain partially favorable to the Kerguelen species. The authors specify that these projections are not extinction forecasts. The sequenced genomes will also be used to study avian influenza, which currently affects penguins, birds, and mammals worldwide. Juliana Vianna, who co-led the study and teaches at the Andrés Bello University in Santiago, Chile, is already searching for mutations associated with survival against the virus to identify the most threatened populations.