And now researchers have found the earliest evidence of right handedness, dating back 1.8 million years.
The discovery was made after researchers examined linear markings on the teeth of a Homo habilis - or early human - fossil.
The fossil, known as OH-65, was originally found in 2003 in a stream channel of the Olduvai Gorge in Tanzania.
The gorge is thought to be one of the most important paleoanthropological sites in the world and has yielded scores of remains of early humans.An international team of researchers from various universities around the world analyzed ridges which were found only on the lip side the specimen's upper front teeth and found that most of the cut marks veered from left down to the right.
They believe they came from when OH-65 used a tool with its right hand to cut food that it was holding in its mouth, while pulling the morsel with the left hand.
While the markings can be seen with the naked eye, a microscope was used to precisely determine their alignment and angulation.
'Experimental work has shown these scratches were most likely produced when a stone tool was used to process material gripped between the anterior teeth and the tool occasionally struck the labial face, leaving a permanent mark on the tooth's surface,' said David Frayer, Kansas University's professor emeritus of anthropology and the lead author of the study.
The direction of the marks of the teeth led the researchers to conclude that Homo habilis was right-handed.
EARLY ANCESTORS USED THEIR HANDS LIKE HUMANS
Around 2.6 million years ago, the first stone tools began appearing in the archaeological record.
In a study published last year, researchers found that our early ancestors may have had the ability to use stone tools around half a million years earlier.
Far from being the fumbling creatures we believed, a look at fossils of Australopithecus africanus reveals the species had human-like hands capable of 'squeeze' gripping.
Dr Matthew Skinner and Dr Tracy Kivell from Kent University analyzed on the internal spongy structure of bone called trabeculae.
This remodels quickly during a lifetime and can reflect the behavior of individuals, as well as how they use their hands.
The researchers compared scans of Australopithecus africanus and modern ape hand bones with scans of hand bones from modern species.
This included a 90,000-year-old Homo sapiens, two roughly 60,000-year-old Neandertals, Romans and Egyptian Nubians who lived between about 1,500 and 2,000 years ago.
They found humans and Neanderthals had hands capable of holding items between the thumb and fingertips.
While the study only consists of a very limited sample of one, the researchers hope it will lead to more investigation into hand dominance in other early Homo species fossils.
'Handedness and language are controlled by different genetic systems, but there is a weak relationship between the two because both functions originate on the left side of the brain,' he said.
'One specimen does not make an incontrovertible case, but as more research is done and more discoveries are made, we predict that right-handedness, cortical reorganization and language capacity will be shown to be important components in the origin of our genus.'
Previous research has pointed to the likelihood that brain reorganization, the use of tools and the use of a dominant hand occurred early on in the human lineage.
While experts estimate that around 90 per cent of modern humans are right handed, apes are thought to have a ratio of around 50-50.
'We already know that Homo habilis had brain lateralization and was more like us than like apes. This extends it to handedness, which is key.'
Until now, no one had looked at the direction of markings on the teeth in the earliest human specimens.
'We think we have the evidence for brain lateralization, handedness and possibly language, so maybe it all fits together in one picture,' Frayer said.
The research was published in the Journal of Human Evolution.
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