>Every living cell is a battery. That is, if you were to stick an=20 electrode inside a cell and another outside that cell, you would get a=20 reading just as if you were measuring a battery with a voltmeter. Catfish=20 can detect these electrical fields in their prey at very minute levels,=20 the equivalent of detecting a flashlight battery at several thousand=20 yards. With single small forage animals, however, the catfish must be very = close ? within an inch or less ? for this method of detection to work.=20 Work it does, though. This sense is extremely beneficial in dark muddy=20 water or when cats are digging in mud or sand to find insect larvae and=20 other invertebrates.=20 Now it's on topic, [EE]. How could we go about duplicating this=20 electrical sensor? What could it be used for? If a lowly catfish can=20 detect the electric field of an animal at an inch, would it be possible to = detect these fields at a couple of meters with a sensitive reciever? We=20 use capacitive recievers all the time in touch sensitive equipment, but=20 this seems to be a different principle, no?=20 -- Lawrence Lile michael brown Sent by: pic microcontroller discussion list 11/22/2003 10:33 AM Please respond to pic microcontroller discussion list =20 To: PICLIST@MITVMA.MIT.EDU cc:=20 Subject: [OT:] - Way OT, but really educational ;-) I happened upon this info when looking up something about catfish. Yeah I know it sounds weird, but bear with me and check it out, it's really fascinating. http://www.thecontentwell.com/Fish=5FGame/Catfish/Catfish=5FSenses.html michael brown -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body