Xenopus laevis larvae (Amphibia, Anura) as model suspension feeders

✍ Scribed by Dianne B. Seale; Karin Hoff; Richard Wassersug

• Book ID: 104613883
• Publisher: Springer
• Year: 1982
• Tongue: English
• Weight: 724 KB
• Volume: 87
• Category: Article
• ISSN: 1573-5141
• DOI: 10.1007/bf00015196

✦ Synopsis

Larvae of the South African clawed frog, Xenopus laevis (Daudin), are efficient, obligate suspension feeders . We examine the relationship between the ambient particle concentration offered these larvae as food and their filtering, ingestion, and buccal pumping rates . We demonstrate that : (i) the larvae can sense and respond to a broad range of particle concentrations, down to 0 .2 mg 1-1 (dry weight) ; (ii) their metabolic needs theoretically can be met by particle concentrations as low as 5 mg 1 -1 ; and (iii) their patterns of regulation of filtering and ingestion fit predictions from certain models used to describe zooplankton feeding dynamics . Two such models are discussed : the modified Monod (Michaelis-Menten) model, with a lower threshold below which the tadpoles do not feed, and an energy optimization model . Both the models and the observed behavior of the tadpoles allow for stability of populations of food organisms . Tadpole feeding dynamics apparently are compatible with both the predictions and assumptions of these models, suggesting similar regulation of feeding by tadpoles and zooplankton . However, the size, morphology, and behavior of X. laevis larvae make their feeding regulation uniquely accessible to direct observation .