Breakthrough Of The Year: Evolution In Action
30th December 2005
BREAKTHROUGH OF THE YEAR:
Evolution in Action
by Elizabeth Culotta and Elizabeth Pennisi
Excerpts:
Today evolution is the foundation of all biology, so basic and all-pervasive that scientists sometimes take its importance for granted. At some level every discovery in biology and medicine rests on it, in much the same way that all terrestrial vertebrates can trace their ancestry back to the first bold fishes to explore land. Each year, researchers worldwide discover enough extraordinary findings tied to evolutionary thinking to fill a book many times as thick as all of Darwin’s works put together.
Amid this outpouring of results, 2005 stands out as a banner year for uncovering the intricacies of how evolution actually proceeds. Concrete genome data allowed researchers to start pinning down the molecular modifications that drive evolutionary change in organisms from viruses to primates. Painstaking field observations shed new light on how populations diverge to form new species–the mystery of mysteries that baffled Darwin himself. Ironically, also this year some segments of American society fought to dilute the teaching of even the basic facts of evolution. With all this in mind, Science has decided to put Darwin in the spotlight by saluting several dramatic discoveries, each of which reveals the laws of evolution in action.
One of the most dramatic results came in September, when an international team published the genome of our closest relative, the chimpanzee. The genome data confirm our close kinship with chimps… the total difference in DNA between our two species [is] about 4%.
2005 was also a standout year for researchers studying the emergence of new species, or speciation. A new species can form when populations of an existing species begin to adapt in different ways and eventually stop interbreeding. . . . This year field biologists recorded compelling examples of that process, some of which featured surprisingly rapid evolution in organisms’ shape and behavior.
Such evolutionary breakthroughs are not just ivory-tower exercises; they hold huge promise for improving human well-being. . . . Humans are highly susceptible to AIDS, coronary heart disease, chronic viral hepatitis, and malignant malarial infections; chimps aren’t. Studying the differences between our species will help pin down the genetic aspects of many such diseases. . . . And in 2005, researchers stepped up to help defend against one of the world’s most urgent biomedical threats: avian influenza. . . . The possible evolution of [an ability to infect humans] in the bird flu now winging its way around the world is why officials worry about a pandemic today.
Source: Science 23 December 2005:
Vol. 310. no. 5756, pp. 1878 - 1879