Most sources state that soup making did not become commonplace until somewhere between 5,000 and 9,000 years ago. It now looks like waterproof and heatproof containers were invented much earlier than previously thought. Harvard University archaeologist Ofer Bar-Yosef and colleagues reported in Science on their finding of 20,000-year-old pottery from a cave in China. "When you look at the pots, you can see that they were in a fire," Bar-Yosef says.
     Their discovery is possibly the world's oldest-known cookware, but exactly what its users were brewing up isn't certain. Perhaps it was alcohol, or maybe it was soup. That kind of container, though, isn't even necessary for boiling. An ancient soup maker could have simply dug a pit, lined it with animal skin or gut, filled his 'pot' with water and dropped in some hot rocks.
     The power of the expanding steam cracks the rocks, a distinct characteristic that first shows up in the archaeological record around 25,000 years ago in Western Europe, says archaeologist John Speth, an emeritus professor of anthropology at the University of Michigan in Ann Arbor.
     But Speth says boiling, and soup, could be even older. "You can boil without using heated stones," Speth realized. All you need is a waterproof container suspended over a fire - the water inside keeps the material from burning. Long-ago cooks could have fashioned such a container from tree bark or the hide of an animal, Speth says. Finding evidence of such boiling, though, would be incredibly difficult because those types of materials usually don't get preserved in the archaeological record.
     Neanderthals were probably cooking in some way, scientists have concluded. A 2011 study from the Proceedings of the National Academy of Sciences found evidence of cooked starch grains embedded in 46,000-year-old fossil Neanderthal teeth from Iraq. "This doesn't prove that they were making soups or stews," Speth says - some have suggested the meal would have resembled oatmeal - "but I would say it's quite likely."
     Putting a date on the world's first bowl of soup is probably impossible. Anthropologists haven't been able to determine for certain when man was first able to control fire, or when cooking itself was invented - though it was likely more than 300,000 years ago, before Homo sapiens first emerged, Harvard primatologist Richard Wrangham says in his book Catching Fire.
     And the story is probably different for people in different parts of the world. It appears that pottery was invented in eastern Asia thousands of years before it emerged in western Asia, Bar-Yosef notes. "Maybe boiling wasn't so important because you had bread" in the West to balance out all that protein, he says. Other parts of the world never had any tradition of boiling food. "A lot of hunter-gatherers didn't use containers at all," Speth says. In places like Tanzania and the Kalahari, there are tribes that didn't boil water until after Europeans arrived. Speth says, though, it's very likely that humans were concocting soup at least 25,000 years ago in some places.

Edited from New Hampshire News (11 February 2013)