When it comes to crafting a bone dagger to use in close combat, what animal should it be made from? Well, according to a new study published this week you should be carving it from a human thigh bone.
Researchers have looked at the bone daggers made by indigenous people from the South Pacific island of Papua New Guninea and found that their past penchant for carving daggers from human bones might have been because they understood that they were the best ones to use, in addition to their spiritual significance. Published in Royal Society Open Science, the study is an unusual one, to say the least.
The warriors of Papua New Guinea would carry the daggers into combat, using them only when the fracas entered the hand-to-hand stage. The sharpened and intricately carved bones were used to finish off an opponent who was injured by long-distance weapons such as spears and arrows, or simply to dispatch anyone else taken off guard.
While today the bone daggers tend to only be carved from the leg bones of the flightless cassowaries that are native to the island, in the past the tribes would occasionally fashion them out of the thigh bones of humans. According to the researchers, the human bones were only taken from respected warriors, and were thought to impart particular honor and status.
But the human bone daggers may have had far more of an advantage over the cassowary weapons than spiritual prestige. Researchers have found that they make stronger and more effective blades, meaning that more pressure could be applied before the bone was likely to fracture and break.
The team tested this by analyzing 11 bone daggers crafted by Papuan tribes, five of which were human and made by people from the Sepik region, while the remaining six were derived from cassowary bones. While most of these daggers came from museum collections, one cassowary dagger was bought from an antique dealer allowing the researchers to physically test its strength to the breaking point in a machine.
The other 10 bone daggers were instead scanned to construct 3D models, enabling the team to test their strength in a computer simulation. It turns out that even though both types of bone daggers have similar material properties, it was the shape of the human bone daggers that gave them an advantage when it came to mechanical strength.
The natural curve in the human thigh bone means that they were able to withstand an impressive 31 percent more force than the cassowary bones, before fracturing. They suspect that the warriors who used the human bone daggers had specifically engineered them to preserve their perceived spiritual value, making them less likely to break and so prolonging their status. The cassowary bone daggers, on the other hand, were much more likely to be used in combat as they were deemed more disposable.
So if you ever need to craft a bone dagger to protect yourself, then maybe you should look for a human femur to work on.