sled

Larger dogs and those bred for specific types of work, such as Arctic sled dogs, "pariah" breeds, and hunting dogs, tended to have higher levels of wolf ancestry.

A decade later, at 69, he joined a two-week expedition to the North Pole, traveling by airplane, skis and dog sleds.

It has been tougher sledding for the stablecoin issuer since then.

The rules vary, but competitions essentially involve pulling a weighted object—usually a cart or sled—16 feet in under a minute.

Each explorer will drag a sled carrying everything they need, from food to equipment and including two ground-penetrating radars to scan through the ice.