Researchers have used mud wasp nests to narrow the age range of Aboriginal rock art in the Kimberley region of Western Australia.

Previous surveys suggested some Kimberley painting were 16,000 years old, but the latest findings proved the Aboriginal rock art was much younger.

"This is the first time we have been able to confidently say Gwion style paintings were created around 12,000 years ago," Damien Finch, doctoral student at the University of Melbourne, said in a news release. "No one has been able present the scientific evidence to say that before."

For the study, published this week in the journal Science Advances, scientists collected and analyzed 100 mud wasp nests from rock art sites.

"A painting beneath a wasp nest must be older than the nest, and a painting on top of a nest must be younger than the nest," Finch said. "If you date enough of the nests, you build up a pattern and can narrow down an age range for paintings in a particular style."

Gwion Gwion paintings, also called Bradshaw rock paintings, are one of the two main regional rock art traditions in Western Australia's Kimberley region.

The paintings, ranging in size from six inches to six feet, feature tall and slender human figures in ornate costume. Many Gwion paintings include figures sporting headdresses, arm bands and anklets.

"The Kimberley contains some of the world's most visually spectacular and geographically extensive records of Indigenous rock art, estimated to include tens of thousands of sites, only a small fraction of which have been studied intensively," said Andy Gleadow, professor of geology at the University of Melbourne.

By pinpointing the age of the Gwion Gwion art tradition, scientists can link the paintings with other kinds of contemporaneous artifacts, giving researchers a better sense of the environment from which the painting emerged.

Prehistoric woman's remains found in underwater cave in Mexico
Washington DC (UPI) Feb 06, 2020 –

Paleontologists have unearthed the 10,000-year-old remains of a prehistoric human on southern Mexico's Yucatán Peninsula.

An international team of researchers determined the ancient bones belonged to a woman. Using a uranium-thorium dating technique, the scientists confirmed the woman lived during the late Pleistocene, at the very end of the last ice age.

"The new discovery emphasizes the importance of the Chan Hol cave and other systems in the Tulum area for understanding the early peopling of the Americas," researchers wrote in a paper describing their discovery, published this week in the journal PLOS One.

At the end of the last ice age, as glaciers melted, sea levels rose and flooded the Chan Hol cave system. Nine other prehistoric skeletons have been previously found in Chan Hol's intricate system of caves.

The ten skeletons recovered from the Chan Hol caves exhibit round-headed, or mesocephalic, cranial features, distinct from the long-headed, or dolicocephalic, characteristics of Paleoindians found in central Mexico and North America.

The difference in skull shape suggests Mexico was peopled by two morphologically distinct groups, possible hailing from two different geographical points of origin. It's also possible a small group of early Paleoindians split off from the first humans to arrive in Mexico and evolved unique cranial characteristics.

Analysis of the prehistoric woman's bones revealed the possible presence of a treponemal bacterial infection, which could have proved fatal. Researchers also found multiple injuries to the skull, but it's likely they happened postmortem.

Cavities in the woman's teeth suggest she at a diet high in sugar. Scientists have also previously found cavities in the teeth of other prehistoric humans found in the Chan Hol caves. In contrast, the worn, cavity-free teeth of Paleonindian previously recovered from central Mexico and North America suggest the group ate hard foods.

The differences in the teeth of the two sets of Paleoindian reinforces the theory that two morphologically distinct groups peopled Mexico during the the late Pleistocene and early Holocene.