The closest we have to humans running wild are the Abos of Australia and the bushmen of So Africa. Yet they use fire. understand that there is not much we can eat without access to fire. And fire was key to simply boiling things causing them to breakdown. Skin and clean a couple of rabbits and birds to throw in the pot. toss in any tubers. The chemistry is all neutralized. Taro and potatoes are both toxic raw. so we never really ran wild unless our stomachs became like those of pigs. That is likely what we did a million years ago. Our primate cousin depends of deer and young pine fronds in springtime. We probably did too .but without the fur coat. Even with fire tech we needed cooperation of the band. so fire likely tamed us and tool making followed. A primitive hot pot can be make from a cured hide pushed down into beach sand and then filled with water. Use fire heated stones to heat the water to boiling. throw in food. That is how every band fed themselves