> "Archaeologists estimate the paintings to be several hundred years old." They don't say what basis was used for the estimate. Age estimates are almost always

> "Archaeologists estimate the paintings to be several hundred years old." They don't say what basis was used for the estimate. Age estimates are almost always a lower bound, except where some radiocarbon date can be established, rare for rocks. We know hominins were in the region 130,000 years ago, based on a butchered mastodon (with major bones split for marrow) found near San Diego. Nobody knows what species, or if they left descendants into the present.