It's not plastic or nuclear weapons are something, what would be common to all advanced civilizations? We well, we went back and forth on this quite a lot, but the essentials are basically energy and an energy perhaps derived from fossil fuels. And then that gives you this carbon isotope marker. That's the, you know, the blep you saw in the geologic record 56 million years ago, right? So then you sa, all, that's perhaps necessary, but that's not sufficient, right?