The researchers made use of the data collected by UK Medical Research Council between 1956 and 2010 in two Gambian villages. The researchers also recorded the mortality and fertility rates among the communities and found that improved nutrition and medical care led to significant shift from low mortality and fertility rates to high rates.
On analyzing the fertility rates, along with height and weight, and found that while natural selection initially favored short and heavier women, it has now favored tall women with a lower body weight.
"This is a reminder that declines in mortality rates do not necessarily mean that evolution stops, but that it changes. Our results are important because the majority of human populations have either recently undergone, or are currently undergoing, a demographic transition from high to low fertility and mortality rates", Dr Ian Rickard said.
The study has been published in the journal Current Biology.