Brrr - it's chilly! Imagine being a penguin and living in Antarctica. The biggest penguin of all, the emperor penguin is famous for a very interesting technique to protect itself against the elements - huddling. Why do emperor penguins huddle? The answer is simply to keep warm. Below is a photograph of emperor penguins huddling together to protect themselves from the harsh Antarctic winds.
Female emperor penguins leave the males in the harsh winter of Antarctica to go looking for food. During this time, the male will be left to take care of the egg and is faced with the challenge of keeping warm. This is where huddling comes in.
Emperor penguins are black with a white belly. Since black is the best absorber of heat it absorbs the heat generated from a penguin's body. The white acts as a reflector - it radiates the heat absorbed by the black onto other penguins in the huddle. Because of this, emperor penguins always huddle with their white underside facing in.
A group of emperor penguins is called a colony. Each colony can have up to a million penguins and up to five thousand penguins can huddle together at one time (while the others are off collecting food for their mates). It is important that there are enough penguins in a colony otherwise there would not be enough heat generated to keep each penguin warm.
Enough penguins need to be in a huddle so enough surface area is protected from the cold. For instance, if there are two penguins in huddle not many penguins would be kept warm and more surface area would be exposed to the cold. But if there were six penguins in a huddle more penguins would be kept warm and there would be less surface area exposed altogether.
Also, penguins have other special structural adaptations to help them survive the cold. They have several layers of feathers and large reserves of body fat that act as insulation. As well as this, the bigger the body the slower it is too loose body heat. This is why emperor penguins have a large, rounded body and are the biggest type of penguin in the world.
For each penguin to have their turn inside the middle of the huddle there needs to be motion. While huddling the emperor penguins slowly rotate around the huddle in a circular motion. The ones on the inside of the huddle motion towards the outside while the ones on the outside move in the opposite direction towards the inside of the huddle. For this to happen the penguins cannot be too squished or too loose otherwise they wouldn't be able to move or would get too cold without the surrounding heat of other penguins.
Feeling chilly? Well, now you know how emperor penguins survive the cold. Maybe you should try it. And here's just a little image to get your feet warmed up.
Thanks for reading,
Author's Note: Information was gathered from http://www.bbc.co.uk/news/science-environment-13616778, http://users.tellurian.net/teach/penguins/index.html and http://www.penguins-world.com/emperor-penguin.html
Other sources are http://www.wired.com/wiredscience/2011/06/penguins-shuffle-warm/ and http://www.neaq.org/education_and_activities/teacher_resources/classroom_resources/teacher_guides/penguin_teacher_guide/penguin_adaptations.php.
Pictures were screen clipped from http://www.bbc.co.uk/news/science-environment-13616778 and Google images.
If you would like to see a video of penguins huddling go to http://www.bbc.co.uk/news/science-environment-13616778