And whales, seals, otters, walruses, etc., all of which have lungs.

I suspect some other basis.

Sticking with the theory though: Maybe they can "see through" us enough to know we're literally just skin and dense bones with very little fat or calories.

That would be more likely.

Technically they are dolphins. But yes, some populations of Orcas do eat other dolphins. Some don't. Their feeding habits seem to be cultural.

autism warning

As most people understand the word "dolphin", Orcas are not technically dolphins though they belong to the same family.

I've heard the claim that Orcas are a species of porpoise, like dolphins, but I can't even corroborate that since Wikipedia is claiming that porpoises are distinct from dolphins.

The clearest explanation I've been able to find comes from this article: https://nextlevelsailing.com/relationship-between-orca-kille...

> The classification of orcas as dolphins stems from their scientific categorization. Both orcas and dolphins fall under the family Delphinidae, which encompasses oceanic dolphins. Despite their formidable size and fearsome reputation, orcas share more in common with their smaller dolphin relatives than with other whale species.

So Orcas and dolphins are both categorized in the family Delphinidae which is colloquially referred to as the "Oceanic Dolphins" so, depending on what you mean, yes Orcas are technically dolphins but then ... so are dolphins. Meaning that "dolphin" and "delphinidae" refer to two distinct things even though all dolphins are delphinidae and the colloquial term for "delphinidae" is "oceanic dolphin." But it's important to recognize that the oceanic dolphins is a pretty wide family that includes several species that have the word "whale" in their name, such as belugas and narwhals, in addition to orcas.

Tbh, just subjectively, they look a lot more dolphiny than whaley to me. They're like dolphins that hit the gym.

And the paint bucket.