At the National Shell Museum, we love to emphasize the immense diversity of mollusks and the cool things they do for a living. When reproducing, many bottom-living marine mollusks, including snails, breed open-water, swimming larvae. The very small sizes of those free-living larvae allow them to drift in the water and be carried by currents and eddies, until the time comes for settling onto the bottom as young adults.
Free-living larvae of some species can stay in open water for several weeks or months before becoming adults. As you can imagine, many of those larvae are carried away to places where they can’t survive, such as areas of open ocean or regions with environmental conditions that may be far from ideal for their survival. Recent experiments by Heidi L. Fuchs (Rutgers University) and her collaborators suggest that the larvae of the Three-lined Mudsnail, Tritia trivitatta, and of the Eastern Mudsnail, Tritia obsoleta, will respond differently after detecting the direction and intensity of waves.
Larvae of the Three-lined Mudsnail potentially react by moving toward the deeper water of the continental shelf, whereas those of the Eastern Mudsnail will tend to stay in or return to bays and inlets. In both cases, their ability to sense motion and low-frequency vibrations allows them to follow courses that are best for effective settlement into the adult life and long-term success of each species. Read more about it here.