By Leslea Hlusko
As biologists explore the variation across the genomes of living people, they’ve found evidence of evolution at work. Particular variants of genes increase or decrease in populations through time. Sometimes this happens by chance. Other times these changes in frequency result from the gene’s helping or hindering individuals’ survival, a phenomenon known as selection. If a gene conferred a survival advantage, people with the mutation would have more offspring and the mutation would become more common in subsequent generations.
Read the full article at The Conversation.