Red hair may be on the rise, according to a new study that points to a surprising evolutionary trend. Researchers from Harvard Medical School have found that natural selection has actively favored the red hair gene, based on an analysis of ancient DNA.
Study Analyzes 16,000 Ancient Genomes
The study examined nearly 16,000 ancient genomes spanning 10,000 years of human evolution. By analyzing this vast dataset, researchers identified a list of traits that nature is actively pushing forward. Among the most prominent were the genetic variants for red hair.
Fox News medical contributor Dr. Janette Nesheiwat provided details on the study from the American Cancer Society, though the source did not provide specifics on her remarks.
Directional Selection Explained
Using new computing methods, the team filtered out random DNA fluctuations to identify what they call “directional selection.” This occurs when a particular gene variant gives an organism a strong survival or reproductive advantage, causing it to become more common in a population faster than by chance.
Prior to this study, scientists knew of only about 21 such instances in human history, one of which was lactose tolerance. This new research uncovered hundreds more instances of directional selection.
Possible Reasons for Red Hair Advantage
“Perhaps having red hair was beneficial 4,000 years ago, or perhaps it came along for the ride with a more important trait,” the authors noted. The study was published in the journal Nature and relied on a large database of ancient DNA from West Eurasia.
“With these new techniques and a large amount of ancient genomic data, we can now watch how selection shaped biology in real time,” said Ali Akbari, first author of the study and senior staff scientist in the lab of Harvard geneticist David Reich.
Frequently Asked Questions
What did the Harvard Medical School study find about red hair evolution?
The study found that natural selection has actively favored the red hair gene, making it one of the most prominent traits identified among hundreds of instances of directional selection.
How many ancient genomes were analyzed in the study on red hair?
The study analyzed nearly 16,000 ancient genomes spanning 10,000 years of human evolution.
What is directional selection and how many instances were found in this study?
Directional selection occurs when a gene variant gives a survival or reproductive advantage, becoming more common faster than by chance. Prior to this study, only about 21 instances were known; this research uncovered hundreds more.
