One of the least understood periods in human evolution may finally be coming into focus.

Archaeologists excavating a prehistoric cave in Israel, estimated to be around 300,000 years old, have unearthed stone tools, animal bones and traces of fire that offer a rare glimpse into the lives of ancient humans.

The remarkably preserved site, described by researchers as a 'time capsule,' has remained sealed since the Acheulo-Yabrudian period, an era marked by major technological innovation and social adaptation.

While the identity of the cave's inhabitants remains uncertain, researchers believe the toolmakers may have belonged to an archaic population ancestral to later Neanderthals and modern humans.

The team suggested that the site captured a pivotal moment in prehistory, when older human traditions were disappearing, and the behaviors that would come to define later human populations were beginning to emerge.

The discovery could help fill critical gaps in scientists' understanding of how our ancestors lived, hunted, used fire and worked together during a poorly documented chapter of prehistory.

Dr Kobi Vardi, head of the Israel Antiquities Authority (IAA) Prehistory Branch and co-director of the excavations, told The Times of Israel: 'This is probably the last culture of a very long continuum [of cultures].

'Between 250,000 years and 50,000 years ago, Homo sapiens and Neanderthals created a totally different culture, so we are right in the moment of transition.'

The identity of the cave's inhabitants remains a mystery because no human remains have been discovered at the site. 

However, researchers believe the toolmakers may have belonged to an archaic human population that lived in the Levant before the emergence of classic Neanderthals and modern humans.

These ancient people may have been part of a transitional population that shared traits with both later groups, occupying a pivotal position in the human family tree. 

The sophisticated stone tools, evidence of hunting and signs of controlled fire suggest they were already displaying behaviors that would later become hallmarks of Neanderthal and Homo sapiens societies.

Some scientists suspect the cave's occupants could have been descendants of earlier populations often grouped under the broad category of Homo heidelbergensis or closely related humans.

Homo heidelbergensis is widely considered the last common ancestor that directly gave rise to both modern humans and Neanderthals.  

The site is located near the town of Fureidis, south of Haifa, and was occupied between 400,000 and 250,000 years ago.

The roof of the cave had collapsed, which experts told The Times of Israel had protected the ancient contents until today. 

This allowed the team to uncover preserved artifacts, including small sharp handaxes, scrapers and blades, from the last phase of the Lower Paleolithic, about 400,000 to 250,000 years ago.

'This is very important because sites from this phase are extremely rare; there are about ten sites in the Near East, two in Syria, one in Lebanon and six in Israel,' Vardi said. 

'However, this is the only site in the Carmel Ridge where this phase was discovered, where we have this culture in pristine condition, meaning not covered by later layers, except for a small part of the cave.' 

The team was able to date the site by analyzing the stone tools recovered from the cave.

According to Vardi, the most common artifacts were side scrapers, a hallmark of the Acheulo-Yabrudian culture. Researchers uncovered around 100 of the tools, which were likely used for tasks such as butchering animals and processing hides.

The excavation also revealed several small, finely crafted handaxes. 

While handaxes were a staple of human technology for roughly a million years during the Paleolithic era, Vardi said the examples found at Fureidis stand out for their advanced design.

Together, the side scrapers and handaxes helped researchers identify the cave's occupants as members of the Acheulo-Yabrudian culture. 

Vardi said the evidence suggests these ancient humans lived in larger and more socially connected groups than their predecessors, although their exact population size remains unknown.

The findings also point to a community with advanced survival skills. 

Researchers found signs that the cave's inhabitants were able to quarry flint from nearby rock outcrops and were accomplished hunters capable of targeting both small prey and larger animals.

The excavation also produced the remains of fallow deer, gazelles, ancient horses and wild cattle bearing signs of human hunting and butchering. Researchers noted that animal bones of this age are seldom found in such good condition.

Evidence from the cave suggests its inhabitants were skilled hunters who lived in relatively large groups, worked stone into sophisticated tools and may have settled near a spring that once flowed beside the site, providing a reliable source of water.