Post details: "Simple" moth ears show unexpected design sophistication

12/21/06

Permalinkby 07:30:12 am, Categories: Literature - Articles, 347 words   English (UK)

"Simple" moth ears show unexpected design sophistication

Moth ears have two or four vibration sensitive cells attached to a small eardrum, and are regarded as among the simplest in the insect world. However, in a recent paper, research findings are said to reveal “unexpected sophistication in one of the simplest ears known”. The complexity comes in the way audio signals are processed so as to enhance the sensitivity of certain frequencies. The language of purpose comes naturally: “the moth cleverly tunes its ear to enhance its detection of bats”. These findings are suggested to impact thinking on the co-evolution of bats and moths, but there is no reason why they should not also impact thinking on design in the natural world. Design-oriented biologists have long abandoned the idea that anything is “primitive”. Wherever we look, the reality is always more than first meets the eye!

Keeping up with Bats: Dynamic Auditory Tuning in a MothJames Frederick Charles Windmill, Joseph Curt Jackson, Elizabeth Jane Tuck, and Daniel Robert
Current Biology, Vol 16, 2418-2423, 19 December 2006

Many night-flying insects evolved ultrasound sensitive ears in response to acoustic predation by echolocating bats [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]. Noctuid moths are most sensitive to frequencies at 20–40 kHz [6], the lower range of bat ultrasound [5, 11, 12, 13]. This may disadvantage the moth because noctuid-hunting bats in particular echolocate at higher frequencies shortly before prey capture [7, 11, 12, 13] and thus improve their echolocation and reduce their acoustic conspicuousness [6, 7, 8, 9, 10, 12, 13, 14, 15, 16]. Yet, moth hearing is not simple; the ear's nonlinear dynamic response shifts its mechanical sensitivity up to high frequencies. Dependent on incident sound intensity, the moth's ear mechanically tunes up and anticipates the high frequencies used by hunting bats. Surprisingly, this tuning is hysteretic, keeping the ear tuned up for the bat's possible return. A mathematical model is constructed for predicting a linear relationship between the ear's mechanical stiffness and sound intensity. This nonlinear mechanical response is a parametric amplitude dependence [17, 18] that may constitute a feature common to other sensory systems. Adding another twist to the coevolutionary arms race between moths and bats, these results reveal unexpected sophistication in one of the simplest ears known and a novel perspective for interpreting bat echolocation calls.

Permalink

Science Literature

March 2010
Mon Tue Wed Thu Fri Sat Sun
<<  <   >  >>
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31        

Search

Linkblog

Links - Groups and Organizations

Links - Of General Interest

  • A Brief View of Time and Those That Live There

    Don Cicchetti blogs on: Culture, Music, Faith, Intelligent Design, Guitar, Audio

    Permalink
  • A Quick Guide to Sequenced Genomes Permalink
  • ARN Related Web Links Permalink
  • Creation/Evolution Quotes

    Australian biologist Stephen E. Jones maintains one of the best origins "quote" databases around. He is meticulous about accuracy and working from original sources.

    Permalink
  • CreationEvolutionDesign

    Most guys going through midlife crisis buy a convertible. Austrialian Stephen E. Jones went back to college to get a biology degree and is now a proponent of ID and common ancestry.

    Permalink
  • Darwinian Fairytales by David Stove

    Complete zipped downloadable pdf copy of David Stove's devastating, and yet hard-to-find, critique of neo-Darwinism entitled "Darwinian Fairytales"

    Permalink
  • ID The Future

    Intelligent Design The Future is a multiple contributor weblog whose participants include the nation's leading design scientists and theorists: biochemist Michael Behe, mathematician William Dembski, astronomer Guillermo Gonzalez, philosophers of science Stephen Meyer, and Jay Richards, philosopher of biology Paul Nelson, molecular biologist Jonathan Wells, and science writer Jonathan Witt. Posts will focus primarily on the intellectual issues at stake in the debate over intelligent design, rather than its implications for education or public policy.

    Permalink
  • John Mark Reynolds Blog

    A Philosopher's Journey: Political and cultural reflections of John Mark N. Reynolds. Dr. Reynolds is Director of the Torrey Honors Institute at
    Biola University.

    Permalink
  • NASA Astronomy Picture of the Day Permalink

Misc

Syndicate this blog XML

What is RSS?

powered by
b2evolution