Jun 09 2009
Just over 20 years ago, the first study using mitochondrial DNA (mtDNA) to trace prehistoric human migrations was published. In this seminal study, scientists managed to determine that all humans alive today can trace their maternal ancestry back to one woman who lived about 200,000 years ago in Africa. The findings were revolutionary, and [...]
Apr 09 2009
How can geneticists tell when a genetic difference between two human populations is an accident and when it’s the result of natural selection?
As our species moved out of Africa and spread out across the globe, there were a lot of chances for random DNA mutations to occur. Many of these were neutral – they didn’t [...]
Oct 02 2008
Before efforts to sequence the human genome began, scientists thought they’d find about 100,000 protein coding genes in the three billion bases pairs of DNA that are found in almost every cell. But much to everyone’s surprise, the true number turned out to be much lower. It’s now thought that the human genome [...]
