title: Speed of back-swimming of Lymnaea.
abstract: The pond snail, Lymnaea stagnalis, can locomote on its back utilizing the surface tension of the water. We have called this form of movement 'back-swimming'. In order to perform this behavior, the snail must flip itself over on its back so that its foot is visible from above. Little is known about the mechanism of this back-swimming. As a first step for the elucidation of this mechanism, we measured the speed of back-swimming of Lymnaea at the different times of the day. They back-swam significantly faster in the morning than just before dark. These data are consistent with our earlier findings on circadian-timed activity pattern in Lymnaea. Lymnaea appear to secrete a thin membrane-like substance from their foot that may allow them to back-swim. To confirm the existence of this substance and to examine whether this substance is hydrophobic or hydrophilic, we applied a detergent onto the foot during back-swimming. A single drop of 1% Tween 20 drifted Lymnaea away that were still kept at the water surface. These results suggest that Lymnaea secrete a hydrophobic substance from their foot that floats to the water surface allowing Lymnaea to back-swim.
authors.affiliation: Biology Club, Hokkaido Sapporo Okadama High School, Higashi-ku, Sapporo 007-0881, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Aono
authors.forename: A
authors.initials: A
authors.lastname: Fusada
authors.forename: Y
authors.initials: Y
authors.lastname: Fusada
authors.forename: W
authors.initials: W
authors.lastname: Ishii
authors.forename: Y
authors.initials: Y
authors.lastname: Kanaya
authors.forename: Mami
authors.initials: M
authors.lastname: Komuro
authors.forename: Kanae
authors.initials: K
authors.lastname: Matsui
authors.forename: S
authors.initials: S
authors.lastname: Meguro
authors.forename: Ayumi
authors.initials: A
authors.lastname: Miyamae
authors.forename: Yurie
authors.initials: Y
authors.lastname: Miyamae
authors.forename: Aya
authors.initials: A
authors.lastname: Murata
authors.forename: Shizuka
authors.initials: S
authors.lastname: Narita
authors.forename: Hiroe
authors.initials: H
authors.lastname: Nozaka
authors.forename: Wakana
authors.initials: W
authors.lastname: Saito
authors.forename: Ayumi
authors.initials: A
authors.lastname: Watanabe
authors.forename: Kaori
authors.initials: K
authors.lastname: Nishikata
authors.forename: A
authors.initials: A
authors.lastname: Kanazawa
authors.forename: Y
authors.initials: Y
authors.lastname: Fujito
authors.forename: R
authors.initials: R
authors.lastname: Okada
authors.forename: K
authors.initials: K
authors.lastname: Lukowiak
authors.forename: E
authors.initials: E
authors.lastname: Ito
mesh_terms: D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology; D003902:Detergents; D057927:Hydrophobic and Hydrophilic Interactions; D008195:Lymnaea / Q000502:physiology*; D013500:Surface Tension; D013550:Swimming / Q000502:physiology; D014867:Water
chemical_list: D003902:Detergents; D014867:Water