Dear colleagues, our co-authors and we are excited to share with you our new publication in Biology Open. We adapted in vitro digestion experiments and investigated the potential influence of motoric movement on the digestion process in odontocetes. The paper is available open-access at: https://journals.biologists.com/bio/article-lookup/doi/10.1242/bio.059440 In vitro forestomach digestion experiments give less-baised estimates of food composition in odontocetes Authors: Klemens, L.; Neven, C.J; Bär, T.; Krumme, U.; Dähne, M. Abstract: Diet composition of odontocetes is usually inferred from stomach content analyses and accounts for digestion rates derived from in vitro digestion experiments based on seal physiology. However, pinnipeds, being carnivores, have only one stomach compartment, while odontocetes, being cetartiodactyla, have up to four. Inappropriate extrapolation from digestion processes in simulated seal stomachs may result in biased estimates of odontocete diets. We simulated a forestomach accounting for muscle contractions and a pH=4 using in vitro experiments with three fish species. Whiting (Merlangius merlangus), black goby (Gobius niger) and sprat (Sprattus sprattus) showed highly variable exponential, sigmoid or linear digestion functions, and high digestion rates, taking between 50 and 230 min for completed digestion. Previous pinniped models (pH=2, lacking simulated muscular digestion) showed much slower and more similar digestion process. Our results suggest that present biomass intake estimates of odontocetes are biased towards bigger and fattier fish and need to be revised in general. Please, do not hesitate to get in touch if you have any questions or suggestions. Best wishes, Lisa and Michael (on behalf of all co-authors)