Humans Are Still Evolving. Natural Selection Has Favored Genes Linked to Red Hair and Less Male-Pattern Baldness, a Study Suggests

Natural selection has played a larger role in shaping modern human DNA than scientists once thought. New research suggests that Homo sapiens have continued to evolve significantly over the last 10,000 years.

Evolution in Modern Humans

A large study, published in Nature, looked at ancient and modern DNA from nearly 16,000 people from West Eurasia. The study found hundreds of gene variants that natural selection has either favored or worked against recently. These include genes linked to red hair and a lower chance of male-pattern baldness.

Michael Berthaume, an anthropologist at King’s College London, noted that people often think human evolution has stopped. However, he explained that humans, as living organisms, will continue to evolve.

Before this study, many scientists believed that modern humans had little evolution after first appearing in Africa about 300,000 years ago. They focused on "directional selection," where a specific gene variant (allele) offers a strong advantage for survival or reproduction. This variant then gets passed on more often. Only about 21 instances of directional selection had been found before this new research.

Uncovering Hidden Signals

The research team spent seven years collecting thousands of DNA sequences from West Eurasian people over the past 10,000 years. They also created a new computer method to separate directional selection from other factors, like human migration, that can change gene frequency.

Their analysis of complete DNA sets (genomes) found 479 alleles that had undergone directional selection. The study mapped when and where these gene variants spread or decreased. It also estimated the overall rate of selection. The results suggest that selection has sped up since humans switched from hunting and gathering to farming.

Ali Akbari, a geneticist at Harvard University and co-author, explained that human evolution didn't slow down; scientists were just missing the signs. He and his team calculated that directional selection accounted for only 2% of the gene frequency changes they observed.

Some alleles strongly favored by natural selection are linked to traits like light skin, red hair, a higher risk of celiac disease, a lower chance of male-pattern baldness, and a lower risk of alcoholism. Many of these variants come from a single change in a DNA unit.

Akbari noted that it's not always clear why certain alleles were selected. A favored allele might contribute to a certain trait now, but that might not be why natural selection chose it. For example, the red hair variant might have been close to another gene that evolution promoted.

Sasha Gusev, a geneticist at Harvard Medical School not involved in the study, expressed some caution about the findings and the statistical methods used.

This research could help develop therapies where doctors modify genes to treat diseases. Akbari suggested that if a variant someone wants to remove was strongly selected for, it might not be the best idea. The new approach could also be used to study other human populations and species, offering more insight into how natural selection shapes life.

Deep Dive & References

• A massive ancient DNA study reveals natural selection has accelerated recent human evolution - Harvard Medical School, 2026
• Human evolution didn't slow down; we were just missing the signal, large DNA study reveals natural selection led to more redheads and less male-pattern baldness - Live Science, 2026
• What is gene therapy? - FDA
• Modern humans (Homo sapiens) - Natural History Museum
• Ancient humans traveled half the world to Asia in main migration out of Africa - Science, 2023