A research team lead by Southern Cross University’s Dr Renaud Joannes-Boyau has revealed for the first time the parenting habits of one of our earliest extinct ancestors.

A paper published in Nature today details analysis of more than two-million-year-old teeth from Australopithecus africanus fossils found in South Africa that show infants were breastfed continuously from birth to about one year of age.

Nursing appears to have continued in a cyclical pattern in the early years for infants as seasonal changes and food shortages caused the mother to supplement gathered foods with breastmilk.

“For the first time, we gained new insight into the way our ancestors raised their young, and how mothers had to supplement solid food intake with breastmilk when resources were scarce,” said geochemist Dr Joannes-Boyau from the Geoarchaeology and Archaeometry Research Group (GARG) at SCU’s Lismore campus.

Team member Dr Luca Fiorenza from Monash University said it was the first direct proof of the maternal roles of one of our earliest ancestors and contributed to our understanding of the history of family dynamics and childhood.

“These finds suggest for the first time the existence of a long-lasting mother-infant bond in Australopithecus,” said Dr Fiorenza, who is an expert in the evolution of human diet at the Monash Biomedicine Discovery Institute (BDI).

“This makes us to rethink on the social organisations among our earliest ancestors.”

An Australopithecus africanus skull. PHOTO: Supplied.

Australopithecus africanus lived from about two to three million years ago during a period of major climatic and ecological change in South Africa, and the species was characterised by a combination of human-like and retained ape-like traits.

While the first fossils of Australopithecus were found almost a century ago, scientists have only now been able to unlock the secrets of how they raised their young, using specialised laser sampling techniques to vaporise microscopic portions on the surface of the tooth.

The gas containing the sample is then analysed for chemical signatures with a mass spectrometer– enabling researchers to develop microscopic geochemical maps which can tell the story of the diet and health of an individual over time.

Dr Joannes-Boyau conducted the analyses at the Geoarchaeology and Archaeometry Research Group at Southern Cross University in Lismore NSW and at the Icahn School of Medicine at Mount Sinai in New York.

The team will now work on species that have evolved since, to develop the first comprehensive record of how infants were raised throughout history.