To go into more detail about one of the mutually beneficial deals: there was research released just this year that rather than following wolves to look for kills, ravens are smart enough to identify where the best hunting grounds are and go there directly to see if any food is around!
“We already knew that ravens can remember stable food sources, like landfills,” Loretto said. “What surprised us is that they also seem to learn in which areas wolf kills are more common. A single kill is unpredictable, but over time some parts of the landscape are more productive than others — and ravens appear to use that pattern to their advantage.”
(when a kill does turn up the ravens don't just freeload either, they act as guard dogs for the wolves by keeping an eye out and alerting if anything suspicious is sneaking up!
I am also obligated and delighted to add that the raven/wolf relationship also extends to playing with the puppies!
Ravens have often been seen interacting with wolves, especially pups and yearlings. These intriguing birds have been known to grab sticks and play tug-of-war with wolf puppies, to fly over young wolves with sticks and tease the small canines into jumping up to grab the sticks, and even to boldly pull the tails of wolves to initiate a reaction. Some scientists have theorized that individual ravens may even develop special bonds with individual wolves within a pack.
I hope we get more research on that last bit, I want to read about ravens with a specific wolf best friend.