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Title: Reconstructing the feeding ecology of Cambrian sponge reefs: the case for active suspension feeding in Archaeocyatha
Sponge-grade Archaeocyatha were early Cambrian biomineralizing metazoans that constructed reefs globally. Despite decades of research, many facets of archaeocyath palaeobiology remain unclear, making it difficult to reconstruct the palaeoecology of Cambrian reef ecosystems. Of specific interest is how these organisms fed; previous experimental studies have suggested that archaeocyaths functioned as passive suspension feeders relying on ambient currents to transport nutrient-rich water into their central cavities. Here, we test this hypothesis using computational fluid dynamics (CFD) simulations of digital models of select archaeocyath species. Our results demonstrate that, given a range of plausible current velocities, there was very little fluid circulation through the skeleton, suggesting obligate passive suspension feeding was unlikely. Comparing our simulation data with exhalent velocities collected from extant sponges, we infer an active suspension feeding lifestyle for archaeocyaths. The combination of active suspension feeding and biomineralization in Archaeocyatha may have facilitated the creation of modern metazoan reef ecosystems.  more » « less
Award ID(s):
2007928 2051255
PAR ID:
10478225
Author(s) / Creator(s):
; ; ; ; ; ;
Editor(s):
Budd, Graham E.
Publisher / Repository:
royalsocietypublishing.org
Date Published:
Journal Name:
Royal Society Open Science
Edition / Version:
1
Volume:
10
Issue:
11
ISSN:
2054-5703
Page Range / eLocation ID:
230766
Subject(s) / Keyword(s):
Evolution Ecology Functional Morphology Cambrian Sponges Computation Fluid Dynamics
Format(s):
Medium: X Size: 2MB Other: pdf
Size(s):
2MB
Sponsoring Org:
National Science Foundation
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