How old are human beings?

Wow!!! What can you learn from an old (400,000) year old thighbone? Matthais Meyer from the Max Planck Institute for Evolutionary Anthropology and colleagues have sequenced the almost complete mitochondrial genome of one of Sima de los Huesos’ inhabitants, who likely lived around 400,000 years ago. That is four times older than the previous record-holder for old bones found and studied (Neanderthal DNA). The bone was part of the fossil remains found in a cave in northern Spain.

The DNA that was uncovered did not cluster with Neanderthals but instead the mitochondrial genome was most closely related to the Denisovans, a sister group to found 4,000 miles to the east, in Siberia.  Meyer was surprised by his findings. This ‘ancestor’ might pre-date the split between Denisovans and Neanderthals.

When we consider old, old mammalian life, then we need to go back to the world’s oldest genome derived from a horse that lived around 700,000 years ago that was buried in Siberian permafrost—ideal conditions for preserving DNA.

What do we know about our more recent history? When did we start using tools? For example, when did we learn to pick our teeth with some sharpened animal bone? OK stop the ridiculous and move on to the real stuff. Turns out that ‘man’ started using fire around 300,000 years ago. How long did it take to have the use of fire catch hold as a terrific tool for all sorts of things including staying warm. How did our ancestors first get the idea of roasting meat for a festive communal barbeque? Would you not have loved to be there when the first of our ancestors discovered fire and then uses?