Science News Roundup: Zambia find shows humans have built with wood for 476,000 years

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Zambia find shows humans have built with wood for 476,000 years

Along the banks of the Kalambo River in Zambia near Africa's second-highest waterfall, archaeologists have excavated two logs of the large-fruited bushwillow tree that were notched, shaped and joined nearly half a million years ago. These artifacts, researchers said on Wednesday, represent the oldest-known example of humans - in this case a species that preceded our own - building wooden structures, a milestone in technological achievement that indicates that our forerunners displayed more ingenuity than previously thought.