Propose to your loved one this Valentine's Day with an onion ring at Red Robin and you might get a free diamond ring valued at up to $10,000, assuming your partner doesn't leave you over it.

Yet these behemoths’ most puzzling feature is a whip-like tail that can measure as long as the rest of the fish’s body. Why mantas and related rays have such long tails has long been a mystery.

They'll move from Pig to Pig,” its founder Robin Hutson tells me. “They’re very keen to tell you how they've collected the set of Pigs, if you know what I mean. You know: ‘we've been to ...