Format

Send to:

Choose Destination
See comment in PubMed Commons below
Nature. 2001 Jul 26;412(6845):439-41.

Crossflow filtration in suspension-feeding fishes.

Author information

  • 1Department of Biology, College of William and Mary, Williamsburg, Virginia 23187-8795, USA. slsand@wm.edu

Abstract

Rows of comb-like or tufted gill rakers in the oral cavity of suspension-feeding fishes (for example, herring, anchovies and tilapia) have been thought to serve as (1) non-porous barriers that direct particle-laden water to the sticky oral roof, where particles are retained as water exits from the oral cavity, (2) conventional dead-end filters that sieve particles from water exiting between rakers, or (3) sticky filters that retain particles encountered by a hydrosol filtration mechanism. Here we present data from computational fluid dynamics and video endoscopy in suspension-feeding fish indicating that the rakers of three distantly related species function instead as a crossflow filter. Particles are concentrated inside the oral cavity as filtrate exits between the rakers, but particles are not retained on the rakers. Instead, the high-velocity crossflow along the rakers carries particles away from the raker surfaces and transports the particles towards the oesophagus. This crossflow prevents particles from clogging the gaps between the rakers, and solves the mystery of particle transport from the rakers to the oesophagus.

Comment in

PMID:
11473318
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Nature Publishing Group
    Loading ...
    Write to the Help Desk