Maternal Secrets from 3 Million B.C.E.

A stunning new research result published in Nature reveals for the first time the breastfeeding and weaning habits of an early human ancestor that lived between 3 and 2 million years ago in South Africa.

Credit: La Trobe University

As part of an international research team – led by Southern Cross University and Monash University – Professor Andy Herries, Head of La Trobe University’s Archaeology and History Department, helped analyse more than two-million-year-old teeth from Australopithecus africanus fossils found in South Africa.

The research team revealed that infants were breastfed continuously from birth to about one year of age. In addition, the study has shown 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 Southern Cross University.

“Australopithecus africanus was the first human species to inhabit what was likely a relatively harsh limestone landscape in South Africa. This research potentially shows that living in these environments was difficult for our early ancestors, particularly as climate began to change around 2.3 to 2 million years ago and this may have led to their ultimate extinction not long after this time,” said Professor Andy Herries, Head of La Trobe University’s Archaeology and History Department.

“These finds suggest for the first time the existence of a long-lasting mother-infant bond in Australopithecus. This makes us to rethink on the social organisations among our earliest ancestors,” said Dr Fiorenza, who is an expert in the evolution of human diet at the Monash Biomedicine Discovery Institute (BDI).

“Fundamentally, our discovery of a reliance by Australopithecus africanus mothers to provide nutritional supplementation for their offspring and use of fallback resources highlights the survival challenges that populations of early human ancestors faced in the past environments of South Africa,” said Dr Adams, an expert in hominin palaeoecology and South Africa sites at the Monash BDI.

For decades there has been speculation about how early ancestors raised their offspring. With this study, the research team has opened a new window into our enigmatic evolutionary history. 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.