If one accepts evolution, then evolution must also be accepted as the cause of global warming: Vast beds of coal evolved in conjunction with mountains of iron ore and growing populations demanding goods and transportation. Given the ingenuity of man, the Industrial Revolution was only a matter of time. Likewise, huge subterranean pools of oil evolved to fill the world with trains, planes, automobiles and giant trucks polluting the atmosphere.
Yes, of course, the globe will warm up, but don't worry about those polar bears. They will simply evolve into omnivorous brown bears. Each day, one anticipates reports of tweed- and calico-colored bears evolving and gamboling along the receding permafrost line.