Biology101

Biology 205

Natural Selection Cuts Broad Swath through Fruit Fly Genome

                This article discusses the impact of how evolution at the genomic level can have an impact on medicine such as drug development. Depending on how many genes are involved in a single trait, it can be next to impossible to determine genetic evolution; as a result, scientists use DNA machines to decode DNA units in “sample genomes of a population undergoing an evolutionary change”.

                The research was started 90 years ago, by Ronald Fisher, Sewall Wright, and J. B. S. Haldane. This article follows the research of Molly K. Burke, Michael R. Rose, and Anthony D. Long from the University of California, Irvine.  These scientists did their experiment on a large population of about 2,000 fruit flies.  They followed 600 generations and 250 genomes. “With each generation the researchers picked the flies that hatched earliest to be the parents of the next generation, and by the end of the experiment, the time to hatching had become 20 percent shorter.” There are two explanations as to why this happened. The “conventional” is called a hard sweep which is when a gene goes through the entire population, getting rid of the rest. However, the process that was accountable for the hatching is called the soft sweep, which is where many genes influence a trait.    

The story contained commentary from other scientists such as Richard Lenski, a evolutionary biologist from the Michigan State University who did a similar experiment on bacteria (multiplies by fission) and Johnathan Pritchard, a geneticists at the University of Chicago.

The experiment was done on 1/8th of the population of fruit flies which may have been a good sample size for this experiment but may not necessarily be a good sample size for the general population. There was only an experimental group and not a control group involved in the experiment. Because the participants to this experiment were...