Supporting Online Material

Surface Tension Transport of Prey by Feeding Shorebirds: The Capillary Ratchet
Manu Prakash, David Quéré, John W. M. Bush

Supporting Online Material

This supplement contains:
SOM Text
Figs. S1 and S2

This file is in Adobe Acrobat PDF format.

Other Supporting Online Material for this manuscript includes the following: (available at
Movies S1 and S2

Movie s1
A juvenile red-necked phalarope feeding. The bird spins on the water surface to generate an upflow that transports the desired prey toward the water surface (B. S. Obst et al., Nature384, 1996). With each dipping event, the bird captures at its beak tip a drop with suspended prey. The high-speed tweezering motion of its beak draws the drop toward its mouth, where the prey is consumed and the drop expelled. [Video courtesy of Don DesJardin]

Movie s2
Droplet transport in a mechanical bird beak of length 1.5 cm and uniform width 1 mm. A water droplet of volume 1.5 ?l is drawn from the tip to the mouth of a mechanical bird beak through the capillary ratcheting mechanism elucidated herein. The tweezering motion of the beak is actuated by a computer-controlled linear motor.

To view these movies, download a QuickTime viewer.