Finding the Elusive Needle

Finding the elusive needle of information

The 2008 March “Physics Today” has an intriguing article on magnetoreception in animals Noting that biological systems often make ingenious use of their physical environment, magnetoreception appears to be no exception. Three interaction mechanisms (detection of induced EMFs as in fish, magnetite, and free radicals as in chryptochrome) are proposed that, in principle, could get useful information from the weak geomagnetic field. However, as the authors point out, determining how animals orient themselves using Earth’s magnetic field can be even more difficult than finding a needle in a haystack. It is like finding a needle in a stack of needles.

Sönke Johnsen and Kenneth J. Lohmann
March 2008, page 29

Link to on-line version is
http://ptonline.aip.org/journals/doc/PHTOAD-ft/vol_61/iss_3/29_1.shtml