Volunteer archaeologists hailing from both France and Spain have just made the remarkable discovery of a 560,000-year-old milk tooth. The tooth is thought to have once belonged to a child that was part of the human sub-species known as homo heidelbergensis.

As Phys.org reports, these sub-species of humans were in many ways similar to homo erectus, from which modern humans have descended.

The milk tooth was recovered by volunteers on Monday night inside Arago Cave, which can be found along the Pyrenees Mountains in France, very close to the border of Spain.

Paleoanthropologist Tony Chevalier has confirmed that researchers believe the child who would have left the 560,000-year-old milk tooth behind was most likely five to six-years-old at the time it was lost.

“The tooth likely belonged to a child aged five or six, who still had their milk teeth but had used them a fair amount.”

Give the age of the milk tooth, this discovery would make it 100,000 years older than the skull of the Tautavel Man, which was also recovered from Arago Cave back in 1971.

Archaeologists have labeled the discovery of the tooth as “exceptional,” especially considering how rare remains that date this far back are, even though researchers have previously discovered teeth from around roughly the same time period here.

Volunteers find 560,000-year-old milk tooth in France https://t.co/v8cwCqqBBI pic.twitter.com/97VQmolOwc — FRANCE 24 English (@France24_en) July 24, 2018

However, while other teeth from this era may have been recovered from Arago Cave, they were not milk teeth.

According to the Daily Mail, research professor Gaël Becam, who works at the European Center for Prehistoric Research, affirmed that this was the oldest child’s tooth to have ever been found here.

“It’s one of the oldest human remains discovered in France, and the oldest child.”

Chevalier noted that archaeologists will now be able to study the 560,000-year-old milk tooth, which will “teach us lots of things about man’s behavior” through time.

For instance, researchers have long wondered what life would have been like for those who resided at the grotto of Tautavel, around the cave.

After having recovered around 150 fossils of ancient humans and human sub-species here, the discovery of this milk tooth may help scientists to finally learn more about the spot in the Arago Cave. Possibilities include it having been a permanent and stable home setting, or, alternately, a more transitory shelter; ancient humans possibly could have stopped for brief breaks there as they foraged for food and hunted.

Gaël Becam explained that another bonus of finding this child’s tooth is that researchers will also be able to learn more about the diets of ancient humans and human sub-species as well.

“By analyzing the marks from use on the tooth, we can learn more about their eating habits for example.”

Once the 560,000-year-old milk tooth found inside Arago Cave in France has been fully analyzed, archaeologists will have a much better idea of how life was lived around the grotto of Tautavel.