Ancient viral DNA in chimpanzee genomes may help explain why human and chimp brains differ

Summary

Humans and chimpanzees share almost all their genes, yet their brains developed differently. Researchers at Lund University in Sweden report that a viral pandemic dating back several million years is likely part of the explanation, with viral DNA left in the chimpanzee genome switching off a gene that is active in humans. Science News describes the infection as a possible influence on chimp brain evolution through these DNA leftovers. 404 Media reports that a family of retroviruses invaded the genomes of chimps and other primates, silencing genes involved in brain development, while humans were left unaffected.

Timeline

1. Phys.org

   23 Oct 2026, 18:00 UTCSource ↗

   Phys.org reports that Lund University researchers have shown a viral pandemic from several million years ago is likely part of the explanation for why human and chimpanzee brains developed differently, with an ancient virus in chimpanzee DNA switching off a gene that is active in humans.

2. Science News

   23 Oct 2026, 18:02 UTCSource ↗

   Science News reports that a viral infection from millions of years ago may have influenced chimp brain evolution through DNA leftovers in the genome, which may help explain why humans' brains surpassed chimps'.

3. 404 Media

   24 Oct 2026, 12:27 UTCSource ↗

   404 Media reports that scientists discovered a family of retroviruses that invaded the genomes of chimps and other primates, silencing genes involved with brain development, while humans were left unaffected.