The Hakubi Project

Despite their name, most Bilateria (to which the majority of animals belong) are not strictly bilaterally symmetric. Snails represent a striking example. Every snail has either a dextral (clockwisely coiling) or a sinistral (counter-clockwisely coiling) shell. The lineages of sinistral snails had been arisen multiple times from dextral ancestors by evolution of left-right reversal. However, because dextral and sinistral snails can hardly copulate with each other, sinistral variants should be selected against by natural selection. Therefore, the origins of sinistral snails had been puzzling. Here, I will talk about how I have solved this mystery by verifying my "right-handed snake hypothesis" and what is the next.