There's jewelry discovered in these Indus Valley civilizations that were based on shells from the Arabian Peninsula. They have materials from China, so there's materials from other parts of India. So once again, a very, very extensive trade network. These civilizations would have known about them. But as we said, they were extremely, they seemed somewhat organized. Even though we can't read their writing, in fact, I have some examples of their writing here. And you might notice, so this is examples of their writing.