Penguins may be colder than Antarctica itself

The reason penguins can stay alive and warm at temperatures that easily reach several dozen degrees below zero is well known: thick feathers and a considerable amount of body fat. What may come as a surprise to some is the fact that some points on the animal's body may have lower temperatures than their typical Antarctic habitat.

This is what revealed a thermophoto published in a study by Biology Letters. As the color pattern reveals (see photo above), some points on the surface of the emperor penguin's body may reach temperatures lower than the ambient ones. "Most of the body that is covered by plumage has been estimated to be on average 4-6 degrees below the surrounding air temperature, " said biophysicist and ecologist Dominic McCafferty of the University of Glasgow.

According to the study, the phenomenon can be explained by what is conventionally called “radiative cooling”. Basically, it is the heat absorbed by the sky itself, noticeable especially during particularly cold and cloudless nights. The internal portion of the animals' body, however, can be stable at 39 degrees Celsius.

It's possible...

As fellow biophysicist and ecologist George Bakken said - in an interview with the Wired website - it is certainly possible that some external portions of the body of emperor penguins may have a lower temperature than the environment. However, he points out that the conditions for the occurrence of radiative cooling are quite specific (as mentioned above).

“It's possible that the temperatures there are a little off. The temperature may not be as cold as they say, ”says Bakken.