Among a colony of black and white penguins with bright orange beaks in Antarctica is one animal that stands boldly apart from the rest. Scientists have discovered that one of the penguins is almost completely white – the result of a rare condition that makes it more susceptible to danger. 

The female penguin belongs to the Gentoo species, animals that typically have bright reddish-orange bills and black heads with white patches around their eyes. But on Jan. 4, researchers at the González Videla Antarctic base found one that looked a little different – it’s almost entirely white. 

The lack of color is caused by a genetic mutation known as leucism. 

“Although pigmentation is present, it is not present across the whole specimen,” veterinarian Diego Penaloza told Reuters, saying there have been similar cases of the mutation across other species, including giraffes, alligators, whales and bison. Unlike albinism, which impacts all melanin production, leucism only has partial effects and does not impact pigment cells in the eyes. 

The condition itself isn’t harmful in and of itself, it can still prove dangerous for the penguin. 

“In this case, being an animal that has a mostly white body, it can make it easier for a predator to hunt it and that is why cases of leucism are also very rare,” Penaloza said. “Because in addition to being recessive genes that are rarely seen, they are also animals that are very exposed – in the case of penguins – to being eaten more easily by a predator.” 

According to the Australian Antarctic Program, Gentoo penguins are the third largest living penguin species, with adults ranging in size from about 11 to 17.5 pounds. In comparison, emperor penguins, the largest living penguin species, can reach nearly 4 feet tall and more than 88 pounds, according to the World Wildlife Fund.

And while gentoos are among the largest in physical size, population size is a different story. These animals “are one of the least numerous Antarctic penguins, with about 300,000 breeding pairs,” according to the British Antarctic Survey. They are also known for having one of the “most prominent” tails of all penguin species with the appendage known for sweeping from side to side as the animals walk, the group says.