The Saharan environment in southwest Libya is a sandy, dry world, but fossil records show it was flowing with water and life some 12,000 years ago.

Paleontologists uncovered 17,551 identifiable remains on the Tadrart Acacus Mountains, with 80 percent belonging to fish that fed early humans during the Holocene period.

The remains show there was once an abundance of catfish and tilapia in the area, which died off from over fishing – the bones had cut marks and traces of burning.

The study also found that tilapia decreased more significantly over time, which may have been because catfish have accessory breathing organs allowing them to breathe air and survive in shallow, high-temperature waters.

These findings reveals the dramatic climate changes that occurred in the area that led to the formation of the world’s largest and hottest desert.

Paleontologists uncovered 17,551 identifiable remains on the Tadrart Acacus Mountains, with 80 percent belonging to fish that fed early humans during the Holocene period. (A and B are both fossilized remains of a catfish, while C and D belong to a tilapia. The fossil E is remains of a crocodile)

‘The remains of both terrestrial and aquatic animals retrieved during the excavation of the Takarkori rock shelter illustrate the more humid climatic conditions in Saharan southwestern Libya during early and middle Holocene times, reads the study published in the open-access journal PLOS ONE by Wim Van Neer from the the Natural History Museum in Belgium, Belgium and Savino di Lernia, Sapienza University of Rome, Italy, and colleagues.

'As the material is so abundant–consisting of 17,551 identifiable remains–and covering a long period–between 10,200 and 4650 years cal BP–it was possible to search for diachronic trends in the faunal spectrum of this unique assemblage.

Approximately 66.4 percent of the fish remains found in the area were Clariidae catfish and 33.6 percent were tilapia.

But what led experts to conclude that they were a huge source of food for settlers in the region were the cut marks and traces of burning on the bones.

The remains show there was once an abundance of catfish and tilapia in the area, which died off from over fishing – the bones had cut marks and traces of burning

The study also found that tilapia decreased more significantly over time, which may have been because catfish have accessory breathing organs allowing them to breathe air and survive in shallow, high-temperature waters. Pictured is the Tadrart Acacus Mountains

Also included in the trove of fossils were remains of mammals, birds, reptiles, mollusc and other amphibians.

Researchers believed that the fish started to disappear as the number of mammals increased, suggesting the humans living in the mountains relied on hunting to survive.

However, the remains suggest that the tilapia may have diminished faster than the catfish – catfish have accessory breathing organs that allow them to survive in shallow, warm water.

‘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,' reads the study

The authors wrote in the paper: 'This study reveals the ancient hydrographic network of the Sahara and its interconnection with the Nile, providing 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