Researchers have discovered some of the oldest tools known to mankind at an archaeological site on the Homa peninsula in southwestern Kenya. It is located east of Lake Victoria. Experts call these implements Oldowan, named after the Olduvai Gorge in Tanzania. They were shaped by human ancestors to produce an amazing variety of hammers and wedges between 2.6 million-1.6 million years ago at the beginning of the Stone Age. Researchers have gained new insight into the Lower Paleolithic period of human evolution by studying this groundbreaking technology. The development of Oldowan was long before widespread agriculture. It led to smarter, better-fed hominins, and may have allowed these early, largely nomadic humans to establish a sense home.

Kanjera South was named after the National Museums of Kenya. It was created in 1987 by the Smithsonian’s Human Origins Program. Richard Potts, paleoanthropologist, started excavations there that summer. The Kenyans were able to work alongside American-educated archaeologists. Thomas Plummer was then a Yale University doctoral student.

Potts claims that Plummer suggested to Potts that the group would discover more archaeological riches if it focused its attention 800 feet to the southwest. It was a stunning stone tool that is approximately two million years old that Potts found with Plummer. This stone, which is on loan from Kenya since 2011, is known as the Kanjera Tool after the location where it was buried. It is the oldest human-made object in any Smithsonian museum collection.

Although the stone looks well-used, there are obvious signs of wear on its many edges. Flakes are visible on the business side of the tool. This is due to a chipping process which created sharpened edges that can be used for cutting. The handle is smooth and flat. It is easy to picture this rock as it was before hominins made it useful--a flat, round stone.

The Smithsonian won't allow visitors to touch the implement, but anyone can feel it fit comfortably in their hands. Potts says the implement is easy to grip and only weighs half a pound. The reddish iron color of the 12 flakes at the sharp end is also notable. This color is usually indicative of a volcanic origin. However, hominins used volcanic rocks as tools. Geological analysis suggests that the Kanjera rock is actually a quartzite, non-volcanic rock. Smithsonian archaeologists believe it was pulled from the ground about five to six miles from Kanjera South. It is most likely that hominins used the Kanjera Tool at other locations before finding its final resting spot.

A hominin would use the hammer stone to make a Kanjera stone. This creates sharp edges that can cut different materials from animal flesh to plants to wood. Our ancestors inventing sharper tools like the Oldowan means that all kinds of food in Africa's savanna, including grasslands and wetlands, became available. Hominins were able to cut and prepare tubers and meat became more common as they hunted antelopes and other prey such as lions. Kanjera South researchers discovered animal bones that date back to the same period, some of which were scarred by stones tools. This is the first evidence of human carnivory.

Potts claims that these novel Oldowan helped hominins adapt to an impressive array environments. Their diet consisted of "everything an animal could eat African environments in a very dynamic world of environment change." Some researchers even believe that this diet led to an increase of the size of the human brain.

The Kanjera Stone is perhaps even more important. It evokes a time of transition from an itinerant existence to one rooted in a specific place. Kanjera South was the headquarters of the first generation to develop these tools. Further excavations have revealed that these early humans made "repeated trips to Kanjera South" over hundreds to thousands years, Briana Pobiner (a paleoanthropologist at the Smithsonian Human Origins Program) once wrote. These ancestors collected quartzite rocks from the surrounding areas as they traveled, and returned to Kanjera south over and over again to make tools, gather food, and live. Potts states that there is a hint that this area is the beginning of a feeling of home for early human beings.

This article is a selection of the July/August issue Smithsonian magazine.