Anthropologists in the United Kingdom have created what they believe is the most accurate Neanderthal model to date from a skeleton found in France over a century ago.

In 1909, excavators searching La Ferrassie caves in the southwest of France unearthed a group of Neanderthal skeletons. Among them was an adult male that researchers named La Ferrassie 1. La Ferrassie 1, who is now about 70,000 years old, is considered to be one of the most important discoveries for Neanderthal research. His skull is the largest and most complete found to date, and his leg and foot bones proved to researchers that the species walked upright - contradicting years of scientific research.

According to BBC, researchers had previously been aware that Neanderthals were stocky, with strong arms and hands. Neanderthals also have large skulls - longer and lower than our own - with sloping foreheads and no chin.

Researchers ran into problems when they decided to recreate the man, because the skeleton of La Ferrassie 1 was missing the thorax, ribs, pelvis, and some spinal bones.

But Viktor Deak, a paleoartist who specializes in reconstructions, made do with copies of the finds of another excavation. That excavation, a 1982 dig at the Kebara Cave in Israel, unearthed a nearly complete skeleton. The only bones missing were the cranium, right leg, and a portion of the left leg.

After piecing together a skeleton, the researchers were faced with the daunting task of recreating the muscles. Jez Gibson-Harris, leading the team of model-makers, noted that the size and texture of the bones hinted at the type of muscle in the area and where they were attached.

The bones also clued researchers into the Neanderthals' lifestyle. La Ferrassie 1's arm bones were asymmetrical, which can occur through strenuous exercise and activities. While the Neanderthals' hunting and chores were rigorous, the Neanderthals' most taxing activity was to create a new piece of clothing for the cold weather each year. The garments were created from five or six animal hides, and La Ferrassie would have needed to scrape the vestment for eight hours in order to make it comfortable to wear.

For his face, the researchers examined La Ferrassie 1's teeth, which had luckily still been attached to his skull. Using X-ray technology to determine the teeth's rate of growth, researchers established that Neanderthals' children aged more quickly than did humans, which may be why their species did not survive and ours did.

During the final stage, the model-makers added head and body hair. Because La Ferrassie 1 would have lived in a cold climate, he was given red hair and pale skin. Each strand of hair was painstakingly attached to his body.

The entire effort took two and a half months to complete. Researchers also created a replication of Nariokotome boy, a member of the homo erectus species, as well as Lucy, an Australopithecus afarensis.

The entire process will be shown on the BBC program Prehistoric Autopsy.