October 25, 2012 | David F. Coppedge

Archer Fish Amplifies Muscle with Physics

The secret of the archer fish’s powerful spits has been discovered, and it isn’t powerful muscles.

The fish that shoots bugs out of the air uses physics, a paper in PLoS ONE declared.  By letting physics amplify the momentum in the drop shot out of the water, the fish achieves six times the wallop its own muscles can attain.  Nature News posted a video of the fish and described how it works:

The researchers found that the first section of the water to leave the fish’s mouth was traveling about two meters per second. But as the fish continued to expel water into the jet, the speed increased. This back-end power forced more water and momentum into the “head” of the jet. “As a result, the power that the head of the jet can deliver upon impact increases during shooting,” the authors explained in their paper.

Vailati and team found that this is similar to a mechanism used by on-demand inkjet printers.  In a strange symbiosis of biomimetics, printer engineers may be able to improve their designs by studying how the fish accomplishes what they came up with independently.

Nature News also quoted the authors’ evolutionary inclinations from their paper:

The fish’s strategy is evolutionarily clever. “This advantage would come without the evolutionary cost for the development of highly specialized internal structures dedicated to the storing of mechanical energy,” the authors noted.

See also PhysOrg and BBC News.   Source: Vailati A, Zinnato L, Cerbino R (2012) How Archer Fish Achieve a Powerful Impact: Hydrodynamic Instability of a Pulsed Jet in Toxotes jaculatrix. PLoS ONE 7(10): e47867. doi:10.1371/journal.pone.0047867.

Evolution is not clever.  Evolution does not calculate the cost of development.  Evolution does not design specialized internal structures dedicated to the storing of mechanical energy.  Once again, we see evolution tacked on to a design story like some kind of vestigial organ from the 1800’s.

The archer fish was one of the illustrations of design used by early films from Moody Institute of Science.  It remains a good illustration today, in fact, even more so.   There’s much more than muscle involved.  The fish has to correct for distortion at the air-water interface, have a perfect aim, calculate the height, and know the energy required to get the bug to release its strong grip on the twig.  All these things must work together for the fish to eat.  How many archer fish had to die before the right mutations came along?  Get real; get intelligent design.


(Visited 194 times, 1 visits today)


Leave a Reply