An analysis of fossilized tooth enamel from three Australopithecus bahrelghazali individuals suggests that they ate primarily tropical grasses and sedges. “No African great apes, including chimpanzees, eat this type of food despite the fact that it grows in abundance in tropical and subtropical regions,” said Julia Lee-Thorp of Oxford University. These very early human ancestors lived in central Africa 3.5 million years ago, so their diet may have diverged from that of great apes earlier than had been thought. Similar results would have been obtained if the hominins had been eating other animals that had eaten the plants, which grew in landscapes with few trees. The teeth are not sharp like carnivore teeth, however.
Meanwhile, at the European Synchrotron Radiation Facility, dental physical scientists are learning how tooth enamel is laid down as a person grows from a child into an adult. It had been thought that enamel forms in layers, much like tree rings, but tests of ancient teeth conducted with a new x-ray diffraction technique suggest that the process is much more complex. “The research is the first step towards a truly accurate four-dimensional model of enamel growth that will allow scientists to more accurately interpret the movements and feeding habits of ancient people,” said Maisoon Al-Jawad of Queen Mary’s University.
It had been assumed that stone pipes and other artifacts excavated from southern Ohio’s Tremper Mound in the early twentieth century were carved from local stone some 2,000 years ago. Yet a new investigation shows that most of the stone and perhaps even the finished objects themselves were imported from Illinois and Minnesota. The Hopewell people of southern Ohio are also known to have collected obsidian from Wyoming, mica from the Appalachians, shells from the Gulf Coast, and exotic animal skulls from distant regions. “Strange animals, strange minerals, strange things were really a focus,” said Thomas Emerson of the University of Illinois.
And, it had been thought that pottery styles in Troy changed after the Trojan War because the Trojans were forced out and replaced by different populations. But chemical analysis of pre- and post-war pottery from Troy indicates that the clay for all of the vessels came from the same local sources. “There is substantial evidence for cultural continuity,” said Peter Grave of the University of New England in Armidale, Australia. He adds that the change in style could reflect a desire to align with the new political elites in the region.
The ancient Maya used three different calendars to keep track of time: a 260-day sacred calendar used for scheduling religious ceremonies; a 365-day secular calendar; and the 144,000-day, or 400-year Long Count calendar. The end of the thirteenth cycle of this calendar will end tomorrow. “You’ll get up in the morning and go forward, and the Maya cycles will have clicked over another day,” explained Walter Witschey of Longwood University.