An amateur archaeologist exploring a dried-out, ancient stream channel called Blackwater Draw near Clovis, New Mexico, made a startling discovery in 1929. He came across chiseled stone points strewn among mammoth fossils. Razor-sharp edges bordering each artifact gracefully curved up to a pointed tip. Thin grooves chipped into the bases of these stone points suggested that they were spearpoints that people had once attached to handles or poles.
Researchers who examined the Blackwater Draw finds saw them as clear evidence of mammoths having been killed by human hunters sometime in the past. Ensuing generations of archaeologists filled out the picture of an intrepid mammoth-killing bunch, dubbed the Clovis people, who spread across North America between around 13,500 and 12,500 years ago. Clovis points or skeletal damage presumably caused by them have been found among mammoth bones at 11 North American sites, including Blackwater Draw. Two other North American sites containing mastodon bones, one featuring remains of extinct elephant-like creatures called gomphotheres, plus a site that yielded camel and horse fossils also include Clovis points or evidence of injuries from sharp, pointed stones (SN: 8/9/14, p. 7).
Archaeologists typically refer to these places as kill sites. It’s long been assumed that Clovis hunters must have left spearpoints lying among the bones of mammoths and other massive creatures after killing and butchering them. If so, Clovis big-game hunters possibly contributed to the extinction of their enormous prey (SN: 11/24/18, p. 22).
But the Clovis people’s status as adept killers of tusked beasts weighing up to about 9 metric tons has come under fire. New experimental and archaeological studies suggest an entirely different scenario, says archaeologist Metin Eren of Kent State University in Ohio. Clovis points had many uses, like a Swiss Army knife, Eren contends. Spear-throwing hunters might have occasionally killed a mammoth, especially one separated from its group or slowed due to injury. More often, these tools served as knives to cut meat off carcasses of already dead mammoths or as dart tips hurled to scare away other scavenging animals drawn to mammoth remains, Eren and his colleagues conclude in the October Journal of Archaeological Science: Reports.
“It’s not clear that Clovis points attached to spears could even have penetrated a mammoth’s hide,” Eren says. “We need to stop assuming that Clovis people and earlier Stone Age groups [in Asia and Europe] must have been mammoth hunters.”
His argument has been greeted with interested skepticism by some Clovis investigators. “We have an instrument, the Clovis point, that keeps showing up in direct association with dead [mammoth] bodies,” says archaeologist David Kilby of Texas State University in San Marcos. “I remain convinced that Clovis points were designed to serve as reliable hunting weapons.”
Eren made the same argument not too long ago. A spear tipped with a Clovis point and hurled from a spear thrower “could have easily taken down the largest Stone Age beasts,” he said on camera in an episode of the 2015 PBS documentary series First Peoples.
Since then, several lines of evidence have led Eren to retract that claim. Crucial clues came from reconstructions of mammoths’ skeletal and internal anatomy — both from earlier studies by other researchers, as well as new evidence gathered by Eren’s group. The reconstructions show how well-protected these creatures were from spears heaved or thrust at them.
Eren’s team combined measurements from Asian woolly mammoths and Columbian mammoths of North America, the presumed prey of Clovis people. Several frozen carcasses recovered in Asia indicate that woolly mammoth skin was 2 to 3 centimeters thick on average, the group estimates. Beneath the skin lay 8 to 9 centimeters of fat. And above that skin, woolly mammoth hides were covered by 5 to 15 centimeters of dense underfur topped by a layer of outer hairs 10 to 60 centimeters long.
Using measurements of ribs from two Columbian mammoths, whose remains are mounted at a Texas museum, Eren’s team then estimated how far a Clovis spearpoint had to travel to reach vulnerable internal organs.
A Clovis point had to plunge 17 to 30 centimeters deep to kill an Asian woolly mammoth, the team calculated. The distance would be close, but not quite as deep, for Columbian mammoths, which may have lacked underfur.
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Even after slicing through hair, hide, fat and tissue on the way into a mammoth’s chest, a Clovis point had to dodge a picket fence of thick ribs to reach the beast’s internal organs. A spearpoint that entered through the stomach and into an opening at the back of the rib cage would have had to travel farther than one aimed at the chest, although it’s unclear how much farther.
With those estimates in mind — and inspired by earlier experiments in which researchers thrust or hurled spears tipped with Clovis points into dead elephants — Eren put the points to the test.
In those earlier elephant experiments, spearpoints often pierced the animals’ hides. But for a variety of reasons that likely included the condition of carcasses and the speeds at which spears were launched, only some points penetrated deep enough to have reached the vital organs of a mammoth or mastodon. Eren used a lab setup that offered a better chance of shooting Clovis points deep into a hunting target than would have been possible in an actual encounter with a mammoth-sized creature. Yet even with this advantage, Eren’s results suggest that Clovis points generally did not penetrate deep enough to have been effective mammoth killers.
In one study published in the July 2020 Lithic Technology, replicas of seven types of Clovis points covering the sizes and shapes that have been found at archaeological sites were fastened to wooden shafts. The sizes ranged from a bullet-shaped point about two-thirds as long as an adult’s thumb to a missile-shaped point nearly as long as a pencil. A bow mounted on a shooting device fired each type of Clovis point 30 times into blocks of moist clay from a distance of about 1.8 meters. Spears traveled at a speed in the upper range of shots that have been propelled by people using spear-throwing tools. The clay blocks, fortified with crystalline silica dust, provided slightly less resistance than the tissue of an elephant or other large animal.
Yet of 93 Clovis points previously found at 15 presumed kill sites, only 12 of 74 discovered among mammoth, mastodon or gomphothere bones had broken, probably after hitting bone, Eren and his colleagues found. In contrast, 10 of 19 Clovis points associated with bison bones — smaller prey with thinner hides likely hunted by Clovis people (SN: 5/13/17, p. 8) — had fragmented due to hard impacts.
Mammoths and their supersized brethren may have fallen prey to Clovis hunters on rare occasions, but the huge beasts would have typically withstood a hail of spears tipped with Clovis points, Eren contends. Even attempts to disable a mammoth by severing tendons in its legs with bladelike Clovis chopping tools attached to handles would probably have failed. In another experiment, Eren swung replicas of such implements at a simulated mammoth foot consisting of a hoof-shaped slab of 5-centimeter-thick clay surrounding beef tendons. Again, in this best-case scenario, chops with Clovis blades sometimes partially cut a tendon but never sliced entirely through one. Often, blades left tendons untouched.