Hydrodynamics of sponge pumps and evolution of the sponge body plan
Abstract
Sponges are suspension feeders that filter vast amounts of water. Pumping is carried out by flagellated chambers that are connected to an inhalant and exhalant canal system. In 'leucon' sponges with relatively high-pressure resistance due to a complex and narrow canal system, pumping and filtering are only possible owing to the presence of a gasket-like structure (forming a canopy above the collar filters). Here we combine numerical and experimental work, and demonstrate how sponges that lack such sealing elements are able to efficiently pump and force the flagella driven flow through their collar filter, thanks to the formation of a 'hydrodynamic gasket' above the collar. Our findings link the architecture of flagellated chambers to that of the canal system, and lend support to the current view that the sponge aquiferous system evolved from an open-type filtration system, and that the first metazoans were filter feeders.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files
Article and author information
Author details
Funding
Danish council for Independent Research (7014-00033B)
- Thomas Kiørboe
Villum Fonden (9278)
- Seyed Saeed Asadzadeh
- Poul Scheel Larsen
- Jens H Walther
NSERC Discovery grant (2016-05446)
- Sally P Leys
Villum Fonden
- Seyed Saeed Asadzadeh
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Raymond E Goldstein, University of Cambridge, United Kingdom
Version history
- Received: July 13, 2020
- Accepted: November 27, 2020
- Accepted Manuscript published: November 30, 2020 (version 1)
- Version of Record published: December 22, 2020 (version 2)
Copyright
© 2020, Asadzadeh et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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