08.27.08
Unsung heroes of evolution
Viruses: The unsung heroes of evolution
27 August 2008
Garry Hamilton
Magazine issue 2671
FEW aspects of evolution are harder to explain than the emergence of complexity. How did the first cell emerge from the primordial soup? How did natural selection come up with a marvel as complex as the human brain? The tree of life is full of similar riddles - great evolutionary advances whose origins defy easy explanation.
Since the discovery of DNA, biologists have insisted they have the answer: complexity arises as the result of small errors that occur when genomes are copied and passed down the generations. Although individually small, these mutations can add up to enormous change across the vastness of time.
This view of evolution has held sway for about 50 years, but now biologists are sensing that it is missing a major element - viruses. For close to a century, these genetic parasites have been regarded as little more than a biological afterthought, notable mainly for their …
The complete article is 2585 words long.