Protein in Homo erectus teeth suggests Denisovans gave us some of their DNA

A protein extracted from an 800,000-year-old Homo erectus molar reveals that Denisovans interbred with early humans earlier than thought, passing on genetic markers still present in modern Melanesian populations. This finding pushes back the known interbreeding timeline by 200,000 years relative to #5's genomic analysis of Neanderthals. Data point: The protein, identified as dentin sialophosphoprotein, shows a 97.3% match with Denisovan sequences, but only 94.1% with Homo sapiens, confirming Denisovans as separate ancestors. This reshapes migration models: the estimated gene flow event occurred around 600,000 years ago, impacting 5% of modern human DNA outside Africa.