Thousands of prehistoric rock carvings – known as petroglyphs – depicting animals, humans, and geometric designs have been discovered in India's western state of Maharashtra, the BBC reports. Archaeologists have absolutely no idea who was responsible for these designs or why they were created in the first place – or how exactly the artists were able to produce recognizable carvings of non-native species, like rhinos and hippopotamuses, that usually reside in Africa.

The vast majority of these petroglyphs were found in the rocky, flat hilltops of the Ratnagiri and Rajapur regions. While a handful are still worshipped by locals, almost all had remained undetected for thousands of years and were found buried under layers of soil and mud. 

What's more, experts believe these may be among some of the oldest examples of petroglyphs in the world, dating back to 10,000 BCE. The style is reminiscent of rock carvings in other countries and continents constructed around this period.

"Our first deduction from examining these petroglyphs is that they were created around 10,000 BC," Tejas Garge, the director of the Maharashtra state archaeology department, told the BBC.

Garge suspects that they were conceived by an as-yet-unknown hunter-gatherer community with little to no experience with agriculture.

"We have not found any pictures of farming activities. But the images depict hunted animals and there's detailing of animal forms," he added. "So this man knew about animals and sea creatures. That indicates he was dependent on hunting for food."

But neither the lost civilization nor the inexplicable purpose of these petroglyphs is the most fascinating part of the story. What's perhaps even more baffling is the subject of some of the designs.

The archaeologists were shocked by the sheer variety of forms. While most would have been scenes and animals familiar to the creators (sharks, whales, and turtles etc), there were also petroglyphs depicting African animals. How on Earth did they know what a rhino or a hippo looked like, the experts now want to know. These species are not currently native to India but it may be that they used to be. Or, perhaps, the people who created the petroglyphs had recently migrated from Africa to India.

The discovery was led by Sudhir Risbood and Manoj Marathe, who found a few petroglyphs in the area and wanted to determine whether or not there were more. Carvings were found in and close to 52 villages – yet only five of those villages realized any existed. 

Now, the state government plans to invest 240 million rupees ($3,200,000) to analyze 400 petroglyphs and get to the bottom of the mystery. 

[H/T: BBC]