Scientists have discovered that ancient Clovis people thrived on mammoth meat during North America’s Ice Age. Photo: Shutterstock According to scientists, the first humans across North America during the last Ice Age preferred mammoths as their main food source. This finding comes from the first direct proof what these ancient people ate.
Researchers analysed the diet of a woman who lived 12,800 years ago. They used chemical clues found in the bones of her son, discovered in the US state of Montana. Since the 18-month-old was still on breast milk at the time of his death, his bones showed the chemical signatures of his mother’s diet.
The diet break-up
Researchers found that her diet was mainly made up of meat from megafauna, the largest animals in an ecosystem. Megafauna made up 96 per cent of her diet, with mammoths accounting for 40 per cent. The rest of her diet included elk, bison, camels and horses. She did not eat many small mammals and plants.
The Clovis culture
The mother and child were discovered to be part of the Clovis culture, which dates back 13,000 years. This group, was always on the move. They are known for artefacts such as large stone spear points for hunting large animals and big stone knives for removing meat from bones.
“These results also help us understand megafaunal extinctions at the end of the last Ice Age, indicating humans may have played a more important role than is sometimes thought,” said Ben Potter, an archaeologist at the University of Alaska Fairbanks and co-lead author of the study.
How scientists studied the diet
How scientists studied the diet
Pieces of the skull and other bones from the child were found in 1968. Researchers carried out stable isotope analysis, focusing on various isotopes of carbon and nitrogen to study the protein portion of his mother’s diet. The mix of isotopes from these elements can provide a chemical signature that shows the type of food eaten – beef or peas, for example.
The researchers estimated that the boy’s diet was made up of two-thirds nursing and one-third solid food.
They compared the mother’s diet to various animals that ate meat or a mix of meat and plants from the same period. Her diet resembled that of Homotherium, a cat which does not exist now and hunted mammoths.
What are stable isotopes and what can they tell us?
Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. Stable isotopes also do not change into other elements.
They are found everywhere in our environment. The isotopes found in the food we eat and the water we drink become part of all our tissues, including our bones. By studying isotopes, scientists can understand a person’s diet and the environment they lived in.
For example, stable nitrogen isotopes can reveal what sort of diet they had (see graphic).