Traditionally, but incorrectly, an assumption exists that more complex organisms have larger genomes. As a result, biologists have tended to view evolution as a process by which organisms amass new genes and functions over time.
But…geneticists Ricard Albalat and Cristian Cañestro warn that this is far too narrow a view. They contend that gene loss, and the loss-of-function that generally accompanies it, may play a large and overlooked role in evolution.
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First, the rate of gene loss is different for different animal phyla. Notice, for instance, that the fruit fly (Drosophila melanogaster) and a roundworm (Caenorhabditis elegans) have lost many more Wnt genes than humans. Second, certain gene loss events may have been crucial to the evolution of entire lifeforms…
Paradoxically, experiments have shown that most genes appear to be nonessential. If given a hearty food supply, some bacteria can do without 90% of their genes.
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Ironically, gene loss itself can be adaptive and confer new traits…From an evolutionary perspective, sometimes less really is more.
The GLP aggregated and excerpted this blog/article to reflect the diversity of news, opinion and analysis. Read full, original post: Losing Genes May Be Just as Important to Evolution as Gaining Them
