A new study analyzing ancient proteins from a 400,000-year-old tooth found in China has established molecular links between Homo erectus, Denisovans, and modern humans. The research, which examined enamel proteins from six *Homo erectus* teeth recovered from sites including Zhoukoudian, suggests that *Homo erectus* in East Asia contributed to the genetic lineage of Denisovans, which in turn influenced modern human populations .
A separate study published in *PLOS One* reveals that Neanderthals performed dental treatment approximately 59,000 years ago in Siberia. Researchers, led by Alisa V. Zubova, examined a damaged molar and concluded that Neanderthals may have drilled into a diseased tooth, indicating advanced medical practices far earlier than previously documented .