A classic example of stabilizing selection comes from historic records of human birth weights, said Kylian Mbappe To Real Madrid Here We Go T-Shirt Hoodie , an evolutionary biologist at Washington University in St. Louis and Stroud’s research adviser. Compilations of birth-weight data in the mid-20th century showed that babies of average weight survived more often than those that were heavier or lighter than average. “Long-term stasis seems to suggest stabilizing selection,” Losos said. “It’s the most favored explanation.” It wasn’t until the early 1980s that scientists developed methods that could test this idea. In 1983, the biologists Russell Lande and Stevan Arnold brought advanced statistics to evolutionary field studies, showing in a landmark Evolution paper how researchers could measure the impact of natural selection within a single generation. The approach, which quantified selection on groups of correlated traits, required biological data sets that were very large