De functie van een kiel bij landslakken

Has the keel (carina) found on shells of landsnails a function? Hutchinson (1989) suggested that a snail uses the shape of the preceding whorl, and particularly the keel on this whorl, as a cue to dictate where upon it the new whorl attaches. Hutchinson suggested experiments to test his ”road-holding model” by manipulating the outline of the penultimate whorl, but did no experiments himself. Unpublished experiments by Antonio Checa with Sphincterochila candidissima support this model. This species has a distinct keel in juvenile specimens only (fig 1a). By eroding the original keel and adding a new one higher or lower on the whorl he could manipulate shellform to lower or higher spirals than normal for this species. This may answer a question raised by Meeuse (1995) in this ""Correspondentieblad"" on the function of a keel in landsnails.