Feel Short? Blame Your Ancestors

Feb. 20, 2008 -- The average height of people within today's ethnic groups may reveal where their distant ancestors lived and could provide lifestyle clues about these long-lost relatives, suggests new research that links past population density and location to the evolution of human body size.

The findings acknowledge that height can widely differ among even individual family members. Nevertheless, each society illustrates a distinctive body size, with some groups being shorter or taller on average than others.

"Of course there is considerable variation within societies that relates to many different nutritional, genetic and perhaps even selection pressures," co-author Robert Walker explained to Discovery News.

"But despite this variation [within societies], the mean body size varies widely -- by a factor of two -- across societies," he added. "So your average Agta (an indigenous Philippine group) is much smaller than your average Inuit (an indigenous Arctic dwelling group)."

Analysis of average adult heights across the world places Croatian and Dutch individuals towards the top of the height spectrum. Pastoralist groups that have long been involved in nomadic tending of livestock also tend to be tall. These groups include the Dinka, the Maasai, the Turkana and the Tutsi.

Walker, a postdoctoral researcher at the Max Planck Institute for Evolutionary Anthropology, and colleague Marcus Hamilton focused on existing hunter-gatherer groups, such as Pygmies, Philippine Negritos and Andaman Islanders, who tend to fall into the shorter end of the height spectrum.

The scientists collected data on 32 such groups, paying attention to the ecology, population density and female adult body size for each named society. Their findings are published in this month's Current Anthropology.

"We focused on female adult body mass because we wanted to relate the variation back to female reproduction," Walker said, adding that earlier first periods relate to earlier first births.