New discovery suggests humans started using bone tools earlier than previous estimations

Archaeologists have announced a discovery that puts the first use of bone tools back 1.5 million years. The finding included nearly 30 knives carved by the human ancestor Homo erectus in Tanzania. Host Marco Werman speaks with the lead archaeologist on the team behind the discovery, Ignacio de la Torre. He's a professor in archaeology for the Spanish National Research Council in Madrid.