By Victoria Woollaston PUBLISHED: 15:15 EST, 16 December 2013 | UPDATED: 15:15 EST, 16 December 2013 The discovery of a human bone in East Africa may finally reveal the mystery of when our hands evolved to be able to use tools. Researchers from Missouri found the bone, which has a unique projection that helps it to connect it to the wrist, in Kenya and it is thought to have belonged to early ancestor Homo erectus. Until now the unique bone structure has only been seen in modern-day humans and Neanderthals, and the discovery means the feature may have evolved more half a million years earlier than previously thought.
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A bone found in Kenya is the earliest evidence of a modern human hand
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It is the third metacarpal which connects to the middle finger and the wrist
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There is a projection at the end of the bone which is unique to humans
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This feature is called a ‘styloid process’ and helps us to grip and use tools
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The bone dates back 1.42 million years - half a million years before previously thought
The earliest fossil evidence ever found of @placeholder dates back 1.8 million years and originated in Africa.