A more varied diet, including the consumption of meat, may have led to the development of brain capacity in human ancestors in South Africa, according to a new report.

The research shed light on the diet of early hominims belonging to three different genera, Australopithecus, Paranthropus and Homo (human beings).

The scientists found that Australopithecus had a more varied diet than both early human beings and Paranthropus.

Scientists conducted an analysis of fossil teeth found in areas such as Sterkfontein, Swartkrans and Kromdraai in the Cradle of Humankind before publishing their findings in the journal Nature, the University of Witwatersrand said in a statement.

Among the scientists who co-published the research was Wits Institute of for Human Evolution director Prof Francis Thackeray.

Thackeray believes the results of the study show that Paranthropus had a diet that was primarily plant-based while early humans ate more meat.

"Thackeray states that the greater consumption of meat in the diet of early forms of Homo could have contributed to the increase in brain size in this genus," read the statement.

Australopithecus was also omnivorous, eating both meat and the leaves and fruits of woody plants.

This diet may have varied seasonally.

The study found that the territory used by each of the three hominims were about the same size.