How closely are you related to a Neanderthal?
Scientists have completed sequencing the Neanderthal genome. It was the first time the entire genome of an extinct hominid had been sequenced. Four billion DNA base pairs were sequenced from three Neanderthal fossils over 38,000 years old. This research aims to determine how closely we are related to Neanderthals by examining our genetic relationship, and also to identify the genetic changes linked to the development of modern human characteristics.
How is DNA like a clock?
As DNA passes from one generation to the next, it acquires small changes, known as mutations. Scientists estimate that after a million years, 2-4% of any stretch of animal DNA will have changed. By measuring the number of DNA changes between peoples from different parts of the world, scientists can calculate when they separated. This 'DNA clock' also tells us that the last common ancestor of chimps and humans lived about 350,000 generations ago: about 5 million years.
How long does DNA last? Nearly all your cells contain DNA, and there may be traces in your body long after your death. Short fragments of DNA may last for 50,000 to 100,000 years before water, air and microbes finally destroy them. Eventually, even the DNA in insects trapped in amber decays, and is lost forever – so ideas from the movie Jurassic Park are, and always will be, just fiction.