A coyote and wolf are two different species. They do not breed in the wild. You must differentiate between selective breeding and natural selection.
Don't get confused by Darwin's example of selective breeding in Origin of Species. He didn't mean to say it was identical.
It is probale that all, under proper conditions, can crossbreed, just as a lion can breed a tiger and create offspring.
It is well known that Canis lupus will breed Canis domesticus without provocation. It is also well known that CAnis latrans will do likewise, without prompting.