A large number of remains of animals–including fish–were discovered by archaeologists at a site in the Sahara Desert, bringing new light on the ancient peoples that once lived there.
According to a report published in the open-access journal PLOS ONE, on recent investigations into the Takarkori rock shelter in the southwestern Libyan Acacus Mountains, nearly 18,000 individual species were discovered, of which approximately 80 percent were fish — such as catfish and tilapia.
The fossils are evidence of 10,200 to 4,650 years ago covering most of the early middle and the current geological period of the Holocene epoch. The fossils were mammals (about 19%), while the researchers found a limited number of insects, rodents, molluscs, and amphibians, too.
Archeologists quarried from the Tadrart Acacus mountains in the Saharan Desert excavated bones of fish, toads, frogs, crocodiles, and birds.
The researchers say the remains of animals were human food waste, because they showed cut marks and burning signs. This has implications for our understanding of the people who used to live in the region, which indicates fish was an significant food.
“The key findings are no doubt the fish remains. Although not uncommon in early Holocene contexts across North Africa, the quantity of fish we have found and studied are unprecedented in the central Sahara,” Savino di Lernia, from the Sapienza University of Rome and the University of the Witwatersrand, South Africa
“The study adds fresh information about climate change as well as cultural adaptations. It is particularly intriguing that fish was common also in the diet of early herders.”
“I believe that the quantity of fish remains in the earliest layers of occupation is really stunning. I particularly liked the fact that early herders were quite good fishers, and fish was an important staple food,” he said.
Today, the environment of the Acacus Mountains is windy, hot and extremely dry. But the fossil record here indicates that for large parts of the early and middle Holocene, the region—like other areas of the Central Sahara—was humid and rich in water, as well as plants and animals. During this period, the area was also home to prehistoric humans who left behind several notable rock art sites.
But over thousands of years, the area became increasingly dry and, thus, less capable of sustaining standing bodies of water that are home to fish. This change in the climate is reflected in the study results.
Around 90 percent of all the animal remains dated to between 10,200 to 8,000 years ago were fish. However, this figure decreases to 40 percent for those dated to between 5,900 and 4,650 years ago.
This changing environment forced the hunter-gatherers who once relied on the fish to adapt and alter their diet, with the researchers documenting a shift towards eating more mammals over time.
According to the authors, the results provide, “crucial information on the dramatic climate changes that led to the formation of the largest hot desert in the world.”
“Takarkori rock shelter has once again proved to be a real treasure for African archaeology and beyond: a fundamental place to reconstruct the complex dynamics between ancient human groups and their environment in a changing climate,” they said in a statement.