Polar Exploration, sled dogs

Question
"I just saw a TV special on the Race to the Sout Pole. Why didn't the men bring the sled dogs into the tent for mutual warmth?"  

Answer
Dear Bill,
That's a darned good question, one that stumps me. I don't have experience with sled dogs at work.

I suppose the men had sufficient equipment and were warm enough and the dogs were very comfortable sleeping in their environment. But of course, I am only guessing. Thanks for the interesting question.
Happy Training!
AT