Redrawing the Evolutionary Diagram

25 million. It's not a number of any particular scientific significance. It is, however, the average of weekly viewers boasted by the hit television franchise CSI last season. The immense popularity of the show is due largely to mankind's basic urge to make sense of the world around him. In the case of CSI, the television audience is satisfied in this quest every week, as forensic evidence in the form of blood stains, hair samples and saliva, are combined to make sense out of chaos, order from disorder. The end result is a presumably accurate picture of a past-tense occurrence. In nearly every case, DNA is the key to unlocking the secret of the past.

Like the fictitious forensic scientists and criminologists of the show, real-life evolutionists and anthropologists are hard at work looking for ways in which DNA can help our modern world better understand the changes of the past. However, the answers are elusive, and the clues more so.

Until recently, skull fragments, bits of bone, and fossil records have been the best and most abundant evidence that scientists could use to trace the path from Homo erectus to Homo sapiens. Thanks to the efforts of Mark Stoneking and his colleagues at the Max Planck Institute for Evolutionary Anthropology, the new evolutionary diagram is being redrawn to reflect a more complicated web where a simple linear depiction one stood. The old model, which depicts a stooped skeleton progressively leading towards a more anatomically recognizable modern form, is going the way of the Dodo.

What prompted this change?

The pivotal point in Stoneking's research is, not surprisingly, DNA. Where fossil records fall short of providing vital information, DNA evidence helps scientists to move forward more assuredly in their evolutionary theories. The secrets wound tightly into the double helix, not only helps us to learn about when our ancestors' skeletal systems metamorphosed, but also what that process looked like and how it coincided with the geological shifts.