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

A massive study of ancient and modern DNA from thousands of West Eurasian people has identified nearly 500 genetic variants that evolution has selected for or against in recent history

Margherita Bassi | Daily Correspondent

April 22, 2026

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Many people are familiar with the concept of natural selection and “survival of the fittest.” While modern humans may look like they’ve been at their “fittest” for hundreds of thousands of years, new research hints that Homo sapiens have continued to evolve—to a much greater extent than previously thought—over the past 10,000 years.

In an enormous study published April 15 in the journal Nature, researchers analyzed ancient and modern DNA from nearly 16,000 West Eurasian people. The work reveals hundreds of gene variants that natural selection has either favored or thwarted in relatively recent history, including ones associated with red hair and a lower chance of male-pattern baldness.

“It is often assumed that what we are and what we look like today is the be-all and end-all, the pinnacle of evolution,” Michael Berthaume, an anthropologist and engineer at King’s College London who did not participate in the study, tells the London Times’ Kaya Burgess. But “as a living organism, humans will continue to evolve.”  

Previously, many scientists suspected that modern humans experienced relatively little evolution after arising in Africa around 300,000 years ago. They arrived at the idea by examining directional selection, a type of natural selection in which a specific variant of a gene, called an allele, provides an extreme version of a trait that is very beneficial to survival or reproduction. It continues getting passed to more offspring, and other forms of the gene appear less often in the population. Before the new study, only around 21 occurrences of directional selection had been identified.

So the team behind the new research spent seven years gathering thousands of DNA sequences from West Eurasian people who lived in the past 10,000 years. They also developed a new computational method that could separate directional selection from other factors that could influence changes in gene frequency, such as human migration.

Within the examined complete sets of DNA, or genomes, analyses revealed 479 alleles that had been subjected to directional selection. The work mapped when and where some of the gene variants started to spread or diminish, and the researchers estimated the overall rate of selection. Contrary to previous research, the results suggest that selection has accelerated since humans traded the hunting-gathering lifestyle for farming.

“Human evolution didn’t slow down; we were just missing the signal,” study co-author Ali Akbari, a geneticist at Harvard University, tells Live Science’s Kristina Killgrove. He and his colleagues calculated that directional selection accounted for just 2 percent of the gene frequency changes they saw.  

Some of the alleles that natural selection has strongly favored are associated with traits including light skin tone, red hair, increased risk of celiac disease, lower chance of male-pattern baldness and lower risk of alcoholism. Many of the variants arise from just a single DNA unit change.

Why were some alleles selected more often than others? “My short answer is, I don’t know,” Akbari tells the New York Times’ Carl Zimmer.

Just because a favored allele contributes a certain trait right now doesn’t mean that’s why natural selection chose it, according to the researchers. For instance, the red-hair-linked variant may have simply been near another gene that evolution promoted.

However, “the findings still require a leap of faith,” says Sasha Gusev, a geneticist at Harvard Medical School who was not involved in the work, to the Times. He is cautious about the vast natural selection the researchers say they’ve identified and takes issue with some of their statistical methods.

Still, the research could inform the development of therapies in which doctors modify a person’s genes to treat a disease. “You could speculate that if the variant someone wants to knock out was strongly selected for, it’s probably not the best idea,” Akbari says in a statement.

The team’s new approach could also be used to investigate other human populations, as well as other species, shedding further light on how natural selection has molded—and continues to mold—life on Earth.

Margherita Bassi | Read More

Margherita Bassi is a freelance journalist and trilingual storyteller. Her work has appeared in publications including BBC Travel, Discover magazine, Live Science, Atlas Obscura and Hidden Compass.