 they work incredibly fast and anyone who works with dolphins will tell you they're incredibly quick. You know that they have these extraordinarily quick minds. But one of the things that's extraordinary about sonar is that if you're a dolphin with sonar, they can kind of, it's incredibly accurate. I think they can tell the difference, a difference of a thickness from about a fingernail from about 20 metres away. But they can also look through things. So if a dolphin is looking at you with sonar,