Some 400,000 years ago, ancient hominids living in what is now Israel hunted down their meals and brought the remains back to a site known as Qesem Cave. A team of researchers who analyzed more than 80,000 bones found within the cave noticed that some of them bore odd, heavy cut marks—which, according to a new study published in Science Advances, offers what may be the earliest known evidence of ancient peoples storing food to snack on at a later time.
Most of the bones that the researchers studied came from fallow deer, and most of the strange cut marks were found on leg bones known as metapodials. The heavy-handed markings suggested that it took a fair bit of effort to strip the bones, which “make[s] no sense ... because at this part of the bone there is no meat and very little fat,” Barkai tells Nicholas St. Fleur of the New York Times.
Perhaps, the team theorized, the animal skin was dry, and therefore more attached to the bone than fresh skin would have been. It seemed likely that the cave’s occupants were going to all this trouble in order to access bone marrow, which boasts a high caloric value and was often consumed by prehistoric groups. But the fact that the Qesem Cave dwellers were letting the animal remains dry out before feasting on this snack suggests that they were deliberately keeping their food for a later date—a degree of forethought and planning that was previously unknown among Lower Paleolithic peoples.
“It was believed that early hominins were consuming everything they could put their hands on immediately, without storing or preserving or keeping things for later,” Barkai explains.
To prove their hypothesis, the researchers sought to find out whether bone marrow stays nutritious if animal remains are left out to dry. Just as crucially, they wanted to know what it would look like if someone tried to skin bones that had been drying for several weeks.
The scientists thus took 79 red deer metapodials and stored them in three different environmental scenarios for up to nine weeks: outdoors in autumn, outdoors in spring, and in an indoor setting meant to simulate Israel’s climate. After each week that the bones spent outdoors, the researchers tried to remove the animal skins using tools similar to the ones that would have been available to the Qesem Cave inhabitants. (They did not process the indoor bones because, as the study authors note, this experiment only “aimed to analyze the sequence of marrow degradation in a similar environment to that of Israel.”)
Chop marks on the bones that had been left to dry for a relatively long period of time looked remarkably similar to the ones on the ancient remains. When the researchers conducted chemical analyses of the marrow, they found that its nutritional value had decreased substantially by week three in the spring and indoor scenarios. But during autumn, the marrow inside bones left to dry outdoors continued to preserve its nutrients until the ninth week. “This fact is interesting because in Qesem Cave, seasonal hunting peaks have been detected that specifically include late summer through autumn,” the study authors note.
Also interesting is the fact that eating old marrow was probably safer than consuming dried meat, because the bone casing would have kept the marrow relatively safe from harmful microbes. As Barkai puts it, “The bones were used as ‘cans’ that preserved the bone marrow for a long period.”
This in turn suggests that the inhabitants of Qesem Cave were capable of savvier culinary innovations than experts had previously thought. “[They] were sophisticated enough, intelligent enough and talented enough to know that it was possible to preserve particular bones of animals under specific conditions, and, when necessary, remove the skin, crack the bone and eat the bone marrow,” says study co-author Avi Gopher.