Measuring cranial variation using geography as a proxy for neutral genetic distances

world globe flushing
Certain anatomical features of the human skeleton are known to vary with geography and climate. To what extent each variable contributes to our physical makeup is less clear. The problem is that populations with similar climate are geographically close to one another. Even if we find shared traits among populations from similar climates it may be just as a result of geographic proximity (and thus clinal gene flow), rather than shared common ancestry.

As I mentioned in my previous post, anthropologists often compared cranial data to matched microsatellite datasets. However, it is rarely possible to get an exact match between the cranial and microsatellite populations. The anthropologist will instead use populations that are genetically similar and which may or may not be representative of the target population. Another option is to substitute microsatellite data with geographic distances, since studies have found a strong correlation between genetic distance and geographic distance (Manica et al. 2005; Ramachandran et al. 2005; Romero et al. 2008). This allows us to get around the need to match phenotypic data with genetic datasets. Read More...