Leaf mechanical properties modulate feeding movements and ingestive success of the pond snail, Lymnaea stagnalis
We examined the mechanical properties of Butterhead and Iceberg lettuce leaves, and the rate at which they were eaten by the pond snail Lymnaea stagnalis. The outer part of Butterhead leaves were less robust than either the inner Butterhead or outer Iceberg leaves (Young’s modulus 2.8, 5.2, 7.7 MPa respectively; ultimate tensile stress 0.18, 0.34 0.51 MPa) which were also thicker. Snails ingested inner Butterhead and Iceberg strips more slowly (36 and 32%) than outer Butterhead. This was not due to differences in latency to first bite or biting rate. Rather, the drop was due to a decrease in the proportion of successful bites (inner Butterhead 84%; Iceberg 86%), to a shorter length ingested per bite (inner Butterhead 55%; Iceberg 45%) and to increased handling time (inner Butterhead 30%). We conclude that sensory input from the mechanically more robust lettuce slows the buccal central pattern generator.
KeywordsLymnaea Mollusc Feeding Lettuce Biomechanics Sensory modulation
We are grateful to Jacob Ward, Bootham School, for help with data collection and analysis.
- Chase R (2002) Behavior and its neural control in gastropod molluscs. OUP, New YorkGoogle Scholar
- Elliott CJH, Benjamin PR (1985a) Interactions of pattern-generating interneurons controlling feeding in Lymnaea stagnalis. J Neurophysiol 54:1396–1411Google Scholar
- Elliott CJH, Benjamin PR (1985b) Interactions of the slow oscillator interneuron with feeding pattern-generating interneurons in Lymnaea stagnalis. J Neurophysiol 54:1412–1421Google Scholar
- Elliott CJH, Andrew T (1991) Temporal analysis of snail feeding rhythms: a three-phase relaxation oscillator. J Exp Biol 157:391–408Google Scholar
- FAO (2006) Food, Agriculture Organisation of the United Nations. http://www.fao.org/documents/show_cdr.asp?url_file=/docrep/007/y5432e/y5432e08.htm
- Hurwitz I, Susswein AJ (1992) Adaptation of feeding sequences in Aplysia oculifera to changes in the load and width of food. J Exp Biol 166:215–235Google Scholar
- Kemenes G, Elliott CJH., Benjamin PR (1986) Chemical and tactile inputs to the Lymnaea feeding system: Effects on behavior and neural circuitry. J Exp Biol 122:113–137Google Scholar
- Siegel S (1956) Nonparametric statistics for the behavioral sciences. McGraw-Hill, New YorkGoogle Scholar
- USDA (2006) United States Department of Agriculture, National Nutrient Database for Standard Reference, Release 17. http://www.nal.usda.gov/fnic/foodcomp/Data/SR17/wtrank/sr17w208.pdf