What's communication like between orcas and dolphins, and even... whales? Could this behavior be learned by, say, blue whales?
The transient subtype of orcas eat dolphins and whales though, so I doubt there's much fraternization there. Humpback whales have been observed interrupting orca attacks on other humpback whales and even otber species.
Blue whales are usually also very calm and do not have teeth (They can still be aggressive in defending themselves or their calves against orcas, who do sometimes hunt Blue whales)