Sure, we use stone in the construction of our buildings, in high-end kitchen countertops and the driveways where we park our cars, but our ancestor’s connection to terra firma was much more a relationship of necessity. Stone once served as the basis for a dizzying array of tools and weapons that helped us weather the harsh world that preceded civilization. More importantly, they helped us succeed as a species.

The fossil record hints that even our most distant ancestors used stone tools. Earlier this month we learned that Australopithecus afarensis, a hominin relation of modern humans used rock blades to carve up dinner some 3.4 million years ago. This pushes stone tool use back nearly a million years before the arrival of Homo habilis, the first member of our genus.

Our ancient relatives' ability to thrive in the face of adversity also appears to have been set, at least partially, in stone. A study covered by Scientific American last summer indicates that small refinements in stone tools led to a population boost in Southern Asia around 38,000 years ago. The boom occurred despite desertification in the area due to a lack of rainfall, which made resources like food and water less plentiful.

And our historical relationship with stone is perhaps brought into greatest relief by the discovery that stone tools helped our species hang on against the threat of extinction around 120,000 to 190,000 years ago. At that time a tiny population of Homo sapiens kept the flame of humanity alive in a world made uninhabitable by an ice age. Using a cadre of stone tools these early humans eked out a living on the southernmost tip of Africa .

These Ice Age survivors are the subject of our recent interactive feature “When the Sea Saved Humanity,” which looks at how a group of only a few hundred individuals hung on against the threat of extinction. Stone tools weren’t necessarily unique to this group, but they played an important role in their hunting, foraging and processing of the spoils. Without this stone technology, our species might have become an evolutionary flash in the pan.

To see how this group of early Homo sapiens crafted their stone tools, watch the video below:




So the next time you’re hiking across a field of boulders or dicing some salad tomatoes on a granite countertop, remember that you have rocks to thank for the very survival of your species. But also thank your lucky stars that you don’t have to cut tomatoes with a stone blade of your own design.