Archaeologists have identified castoreum — a substance harvested from the castor sacs of beavers — as a component of the design and construction of an ancient throwing dart from Yukon, Canada. Photographs of the find location and the 6,000-year-old throwing dart recovered in 2018 in Yukon, Canada: (a) composite photograph of the dart; (b) dart in its discovery location, showing the distal end; (c) dart in its discovery location showing...