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Title: Unifying fluidic excretion across life from cicadas to elephants
Can insects weighing mere grams challenge our current understanding of fluid dynamics in urination, jetting fluids like their larger mammalian counterparts? Current fluid urination models, predominantly formulated for mammals, suggest that jetting is confined to animals over 3 kg, owing to viscous and surface tension constraints at microscales. Our findings defy this paradigm by demonstrating that cicadas—weighing just 2 g—possess the capability for jetting fluids through remarkably small orifices. Using dimensional analysis, we introduce a unifying fluid dynamics scaling framework that accommodates a broad range of taxa, from surface-tension-dominated insects to inertia and gravity-reliant mammals. This study not only refines our understanding of fluid excretion across various species but also highlights its potential relevance in diverse fields such as ecology, evolutionary biology, and biofluid dynamics.  more » « less
Award ID(s):
1941933 2310691 2310741 1806833
PAR ID:
10505682
Author(s) / Creator(s):
;
Publisher / Repository:
PNAS
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
121
Issue:
13
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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