Ancient Peruvians gave themselves elongated skulls as a mark of status

Many heads from pre-Inca societies are ‘teardrop shaped’ – the result of infants’ heads being bound while they are forming

The Collagua people would bind pieces of wood to children's heads to modify the shape of the developing skull (Creative Commons)

Members of the ruling elite in parts of South America would have been very easy to spot 700 years ago – due to their tall, elongated skulls.

Their artificially extended heads were apparently status symbols, and could have helped foster a sense of community and collective identity, according to a study.

Over 300 years before the Inca empire swept the south western Americas, members of a small ethnic community known as the Collagua practised intentional head shaping which developed to focus on creating a tall thin skull shape.

According to bioarchaeologist Matthew Velasco of Cornell University the cranial modifications may have bound the powerful elite together, but it may also have polarised other groups, resulting in social inequality.

The Collagua people lived in the Colca Valley in south-eastern Peru, where they raised Alpacas and llamas for wool.

Early Spanish accounts also detail another ethnic group – the Cavanas, who also populated the region. Spanish records say that in contrast to the tall narrow heads of the Collagua, the Cavanas also modified their skulls, widening and flattening them.

The Collagua would use pieces of wood, which were tightly bound to the heads of infants to modify how their heads grew. The practice was banned by the invading Spanish in the 16th Century.

Mr Velasco’s research, published in the journal Current Anthropology is the first time skull shape has been studied as a class differentiator within the Collagua.

By looking at skull shapes from over 200 individuals from a 300-year period, the research team saw that tall thin skulls became increasingly linked to high social status.

Chemical analysis of the bones revealed that Collagua women with purposefully distended heads were more likely to eat a broader diet than those without cranial modifications. The team also observed that these women typically had fewer injuries from physical attacks than women with unaltered skulls, Science News reports.

The study suggests the changes to head shape among those with power may have helped pave the way for a peaceful incorporation for the Collagua into the Incan empire.

“Greater standardisation of head-shaping practices echoes broader patterns of identity formation across the south-central highlands and may have provided a symbolic basis for the cooperation of elite groups during an era of intensive conflict,” says Mr Velasco.

The intensive conflict was due to the encroaching Incas, who originated from the highlands of Peru and through armed takeovers and assimilation, ultimately controlled most of Peru, as well as large parts of what are now Ecuador, Bolivia, Argentina, and Chile, in addition to a small part of southwest Colombia.

The civilisation was one of the largest empires in the world when it reached its peak in the 16th century before the Spanish conquistadors arrived.