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Title: Incorporating recirculation effects into metrics of feeding performance for current-feeding zooplankton
The feeding performance of zooplankton influences their evolution and can explain their behaviour. A commonly used metric for feeding performance is the volume of fluid that flows through a filtering surface and is scanned for food. Here, we show that such a metric may give incorrect results for organisms that produce recirculatory flows, so that fluid flowing through the filter may have been already filtered of food. In a numerical model, we construct a feeding metric that correctly accounts for recirculation in a sessile model organism inspired by our experimental observations ofVorticellaand its flow field. Our metric tracks the history of current-borne particles to determine if they have already been filtered by the filtering surface. Examining the pathlines of food particles reveals that the capture of fresh particles preferentially involves the tips of cilia, which we corroborate in observations of feedingVorticella. We compare the amount of fresh nutrient particles carried to the organism with other metrics of feeding, and show that metrics that do not take into account the history of particles cannot correctly compute the volume of freshly scanned fluid.  more » « less
Award ID(s):
2027417 1805847
PAR ID:
10579728
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Royal Society Publishing
Date Published:
Journal Name:
Journal of The Royal Society Interface
Volume:
21
Issue:
212
ISSN:
1742-5662
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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