A

nthropologists once believed that tool-

making was humanity’s defining character-

istic, elevating us above other animals. But

beginning in the 1950 s, when field biologists

reported on chimpanzees using sticks to dip

for ants, our toolmaking began to seem less

than special. “Now we must redefine tool, redefine Man, or

accept chimpanzees as humans,” pioneering anthropologist

Louis Leakey wrote in 1960.

We haven’t accepted chimpanzees as human. Nor have

we redefined “tool.” Rather, over the last 50 years, the idea

that tool use is the defining characteristic of human beings

has been discarded. Nowadays we know that chimps, crows,

otters, dolphins, and many other species use some sort of

tool to exploit their environment. This realization has led

anthropologists to redefine “Man,” looking for other traits

that set humans apart. Today, complex social organization and

language are the focus of much scholarly attention.

In recent years, however, a handful of archaeologists have

begun looking at tools in a new way. Just because tools aren’t

exclusive to humans, they posit, doesn’t mean they weren’t

an important driver in our evolution as a species. Tools have

certainly shaped us: The ability to cut, prepare, and cook

food, for example, meant our jaws could be less powerful

and gave us access to more calories for less work. From

stone implements to the iPhone, the kinds of tools modern

humans and our distant ancestors made—and how we learned

to make them—may have shaped our evolutionary path. It’s

the complexity of our tools, the forethought they require,

and the frequency with which we use them that set modern

humans and our closest relatives apart.

42 ARCHAEOLOGY • March/April 2018

An ancient hand ax (below, far left) from the

site of Boxgrove in England and an array of

experimental examples made by modern

flintknappers at various skill levels

Inconveniently, it’s hard to learn much about forethought,

language, and learning from the archaeological record. Our

evidence of the deep past is composed primarily of fossilized

bone fragments and stone tools. Neither can tell us much

about how our ancient human relatives thought, or what

combination of cognitive advances and environmental con-

ditions prompted them to begin making ever more complex

tools. An arc more than three million years long, beginning

with smashing rocks into sharp pebbles and now entering

our modern era of cell phones, electric cars, and spacecraft,

remains shrouded in mystery. Rather than relying on the fossil

record, some archaeologists wondered if examining the brains

of modern humans might offer an entirely new kind of access

to what went on deep in the ancient past.

By studying brain activity during toolmaking and com-

paring it to what neuroscientists already know about how

the brain processes speech and language, they can explore

ideas about how—or if—the two traits are connected. “With

neuroimaging, we’re beginning to test the idea that language

uses the same structures of the brain as stone toolmaking,”

says Shelby Putt, a researcher at the Stone Age Institute in

Bloomington, Indiana.

Here, the archaeological record has a lot to say. Archae-

ologist and hobby flintknapper Alex Woods, now working

for Colorado State University’s Center for Environmental

Management of Military Lands, says that, to the trained eye,

stone tools are unique windows into the thoughts of long-

gone beings that populated the branches of humankind’s

family tree. “You can see a tool, even one that’s millions of

years old, with four or five mistakes in a row that were part

of a thought process. It’s the only time in archaeology where