eldavojohn writes "A recent study puts observed numbers on genome mutations in plants. This kind of research is becoming more popular in understanding evolution. The research 'followed all genetic changes in five lines of the mustard relative Arabidopsis thaliana that occurred during 30 generations. In the genome of the final generation they then searched for differences to the genome of the original ancestor.' A single generation has about a one in 140 million chance of mutating any letter of the genome (which has about 120 million base pairs). Sound like bad odds? From the article, 'if one starts to consider that they occur in the genomes of every member of a species, it becomes clear how fluid the genome is: In a collection of only 60 million Arabidopsis plants, each letter in the genome is changed, on average, once. For an organism that produces thousands of seeds in each generation, 60 million is not such a big number at all.' The academic paper is available in Science, though seeing more than the abstract requires a subscription."