Imagine that researchers have sequenced the genomes of two closely related species of grasshopper.

Last updated: 7/8/2022

Imagine that researchers have sequenced the genomes of two closely related species of grasshopper. One of the species lives in a temperate climate and the other lives in a hotter area. The researchers calculated the dN/dS ratios for a gene that has been associated with a differential ability to handle high temperatures in insects. The calculated dN/dS ratio was 1.5. Which of these statements is most likely to be true about this gene? a. There are more nonsynonymous mutations than synonymous mutations, which implies that the changes have been fixed in the population as a result of positive selection. b. There are more synonymous mutations than nonsynonymous mutations, which implies that any mutations which changed the function of the gene were deleterious and removed via purifying selection. c. The numbers of synonymous and nonsynonymous mutations are almost the same, which means that the changes in this gene between these two species are due to genetic drift. d. The gene doesn't have any mutations or differences between the two species.