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Hey guys, I'm Iqra and this is What's in the World from the BBC World Service.
We're taking you to Antarctica for this one.
When it comes to the icons of the penguin world, the emperor penguin is winning hands down.
To throw a few facts at you, they only live in Antarctica and they're basically Olympic divers.
They can reach depths of over 500 metres and stay underwater for up to 22 minutes.
Crazy.
Also, male emperor penguins have one of the most extreme fasts in the animal kingdom.
They'll not eat for up to four months whilst they breed and look after the egg until it hatches and the mother returns to feed.
In other words, no eating until the queens are back.
And your final fact, they replace all their feathers in one go.
It's called a catastrophic molt and happens once a year.
They can lose 45% of their body mass during this time.