It’s abundantly clear that Neanderthals and other early hominins were capable hunters who made and used spears. But many researchers have argued that such weapons were too heavy and clunky to be thrown quickly or accurately, and could only be thrust into prey from close range. “The general consensus has been that they were limited to ranges of 10 meters,” or about 32 feet, Milks says.

According to this view, long-distance kills became possible only when modern humans invented specialized tools like spear-throwers, atlatls, or bows. Those superior weapons gave their bearers—our ancestors—an advantage over other hominin species, allowing them to safely bring down dangerous game that Neanderthals were forced to engage at close quarters. Perhaps that partly explains why the latter went extinct, while modern humans thrived.

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But to Milks, this narrative always had a glaring problem. “We don’t have good data on how hand-delivered spears performed, so we can’t make a valid comparison,” she says. “The 10-meter distance was repeated over and over again, but not backed up with much evidence.” It came from an influential ethnographic review that considered the spear-throwing skills of many modern populations, but didn’t include adept groups such as the Tasmanian and Tiwi peoples of Australia. And it was bolstered by studies and anecdotal reports in which spears were thrown by anthropologists—hardly a decent stand-in for a skilled Neanderthal hunter.

For example, John Shea, an archaeologist at Stony Brook University, told me that he regularly takes his students into an athletic field and asks them to throw replica Schöningen spears at him. “If they hit me, I pledge to give them $20,” he said. “I’ve been doing this ‘experiment’ for 25 years, and I’ve neither got so much as a scratch on me nor parted with any cash. The spears come sailing in so low and slow I can usually just step sideways out of the way, bat them away with a stick, or if I am feeling really cocky, catch them in midair.”

A German sport scientist and javelin-thrower named Hermann Rieder had more success: In a small study, he managed to hit targets from around 16 feet away and suggested that the spears were useful weapons at longer distances. (A Wikipedia entry that cites his study and claims that “athletes could throw replicas up to 70 meters” is almost certainly wrong.)

To get more thorough data, Milks asked Owen O’Donnell, an expert in reconstructing ancient technology, to create the best possible replicas. He made two from spruce—the same wood as in the Schöningen spears. He built them to the same weight—1.67 and 1.76 pounds, respectively. And he finished them with stone tools to give them an authentic texture.

“I’ve been asked a lot if I threw in my own experiments,” Milks says. “But that wouldn’t tell us anything, other than that I’m a bad thrower.” Instead, she gave the spears to six trained javelin-throwers, whom she filmed with high-speed cameras. The participants hurled the spears both far and fast. It’s sometimes said that heavy spears would slow mid-flight and hit their targets with dull thuds. But Milks found that the replicas slowed very little, and landed with a kinetic wallop comparable to projectiles launched by bows or spear-throwing tools.