A feather boa over a tuxedo: the world's largest penguin chick "dresses up" (video).

The fluffy and large chick of a royal penguin, named Pesto, quickly gained worldwide fame — his photos went viral on social media, as the penguin chick was nearly twice the size of his peers. It is known that Pesto was born at the Sea Life Melbourne aquarium in Australia, and he has now begun the natural molting process, reports Popular Science.

As a result, the once fluffy and large penguin chick has transformed into one who "wears a brown boa over a white tuxedo shirt." However, researchers note that the molting process is entirely natural for royal penguins at this age.

It is worth mentioning that royal penguin Pesto was born at the aquarium in January 2024. His arrival was quite exciting for the aquarium, as not a single chick hatched last year. Moreover, he is also the only chick this year.

Pesto weighed 22.5 kilograms and stood 80 centimeters tall — it was precisely his unusual size that made him famous worldwide. According to Olivia Hill, the education manager at Sea Life Melbourne, Pesto's size is a combination of nature and nurture. The biological father of the chick, a penguin named Blake, is one of the largest penguins in the aquarium, while the chick's adoptive parents, Tango and Hudson, provided him with excellent care.

Researchers note that as Pesto grew, he began to increase in size rapidly and eventually became the largest chick ever to live in the aquarium. However, scientists believe that the penguin will not always remain the biggest.

It is known that Pesto started losing weight after his parents stopped feeding him — it is expected that soon the chick will weigh approximately the same as his peers. Interestingly, Pesto is currently in the molting phase — growing his adult plumage. During the molting process, his old juvenile feathers are pushed out by new black, white, and yellow feathers. This typically occurs once a year for all penguin species and usually lasts two to three weeks.

According to Hill, during the molting process, old feathers fall out, but they also observe that birds sometimes help themselves by removing old feathers. As a result of the molting process, scientists say that Pesto today looks as if he "wears a brown feather boa over a white tuxedo shirt."

Ultimately, aquarium staff believe that Pesto will resemble other adult royal penguins. Adult individuals typically have orange feathers around their beaks, while young ones have dark brown or black feathers. However, researchers respond that there are generally few differences in the plumage of birds, making them difficult to distinguish in the wild.

Hill notes that Pesto will be distinguishable by the dark plate on his beak for the next year or so until he molts into an adult for the first time (this will happen in November 2025), after which he will shed the black plate on his beak and grow an orange plate, indicating that he is an adult. After that, his only distinguishing feature will be a stripe on his wing.