MicrobeWorld

This recent paper prevents evidence that microbes (Escherichia coli and Saccharomyces cerevisiae) can evolve to anticipate environmental change. They show that pre-exposure to a stimulus that usually occurs before a second stimulus (i.e. lactose before maltose in E. coli) will improve the ability of the orgranism to handle the second stimulus. They also performed a "laboratory evolution" experiment and observed loss of this anticipatory response in E. coli strains that were repeatedly exposed only to the first stimulus. This "asymmetric anticipation", along with other associative learning and memory previously observed in microbes, illustrates just how sophisticated, and elegant, their responses have evolved to become.