The recent analysis of chemical information left behind on 11 species of hominins (or early humans) and other East-African primates indicated a remarkable change in diet 3.5 million years ago. The results were published among four papers appearing in PNAS journal.
Hominins once ate a forest-based diet of leaves, fruit, shrubs, and herbs. However, about 3.5 million years ago, the species Australopithecus afarensis and Kenyanthropus platyops dramatically changed their diet, beginning to consume grasses, sedges and possibly other animals. These species lived on the open savannahs of Africa.
Humans began flossing in the late 19th century, with Johnson & Johnson obtaining the first dental floss patent in 1898. Had hominins behaved like modern-day humans and flossed their teeth, these fossils may not have provided nearly as many clues.
"What we have is chemical information on what our ancestors ate, which in simpler terms is like a piece of food stuck between their teeth and preserved for millions of years," said Dr. Zeresenay Alemseged, from the California Academy of Sciences, co-author on two of the papers.
Researchers did not find any diet changes in other animals from this time period after analyzing their teeth fossils.
