> the whole of paleo-anthropology "knew" that humans couldn't boil things until the invention of pottery

Is that really true? That sounds unlikely when there are so many contemporary counterexamples. If you have an interest in cooking, there are several traditional meals where cooking is done in other ways. Especially so for indigenous people who have little access to metals or clay. For example on Borneo the traditional way to cook rice over fire is inside bamboo stalks. As long as the water doesn't boil off, you can cook in almost any vessel.