evolution

Is what the polar bears doing with the grizzly bears considered evolution?

Um... What are polar bears doing with grizzly bears?

Evolution isn't something animals do to each other... So I guess "No, it isn't"? Maybe? I don't know; what are you referring to?

Polar bears mating with Grizzlies for the survival factor; I think is more of an adaptation than evolution...evolution would happen over a very long period of time with subtle changes to the being, gradually. This is happening everytime, quickly. They are distantly related and that's why they can breed but the need for it has not existed until now..

I guess they're breeding! Polar Bears evolved from grizzlies only a few hundred thousand years ago and its long been known they can still interbreed:
http://news.sciencemag.org/biology/2014/05/polar-bear-evolution-was-fast-and-furious

They're doing what they've always done!

It might be happening more now than in the last 70 years because polar bear populations have recovered from around 5,000-8,000 in the 1950's and 1960's to 20,000 - 25,000 today, according to some guesstimates (nobody really knows how many polar bears there are out there . . .)