Well, they were probably doing tests on Polar Bears first, seeing how they acclimatize to warm climate or some crap, and then decided to use them for the wheel, since the Polar Bears were already on Hydra Station before the Wheel was discovered.InaudibleWhispa said:But there is no mystery, they've gave you more than enough pieces to produce an answer. Dharma were training Polar Bears to turn the frozen donkey wheel so that a person isn't transported through time to Tunisia. That is pretty much a fact at this point; the Polar Bear Charlotte found in Tunisia had a Dharma collar on, and it lay in the same position the donkey wheel (a cold environment, hence Polar Bears) moved Ben and Locke to.