ADDE"Mtj'.wf TO PROPOSAL TO SUIPLF.MFI,'T
                                         US GOVERr4MEZIT COh7PACT -
                    Following conversations between the sponsor and cognizant personnel of the
                                         was agreed that a shift Of emphasis in the propo2sed pro-
               ject -,as warrented.  The revised orientation of the proposed research will be
              placed upon the utilization of an electric field by certain species of fresh water
              fish tO navigate, orient and detect small objects as opposed to the original em-
              phasts of phylogenetlc comparisons of learning.
                  In recent years, there has been increasing   Interest in the sensitivity and
   2           response of various organisms to magnetic fields.  This has been particularly
              tcue in the space program, where the effect-s of leaving the Earth's magnetic and
             gravitational fields on mants behavior and physiological  processes  may  be  of
             great importance.  The magrietic field is a form of energy like light, heat, and
             sound,, to which all Plants and animals are exposed. I2ts  Influence  on  living'
             systemst however, is subtle and not well understood.
                 One potentially useful approach to studying the  effee-@s of magnetic fields
            upon behavior is through the use of an organism wh:Echpproduces an electrical   field
            and uses it as a detection and navigation mechanism.  The electric fish
            Sternarchus albifrons is such an organism.  Impulses are discharged 2from the fish's
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            tail and received 'by its head, which becomes positive with regard to  the  tail.
            This difference creates a field about tho fishve body, permitting  it  to  detect
           objects through their distortion of the field.  The purpose of the present study
           will be to determine how Sternarchus orients itself, in   terms of its own  field,
                                     --7-------------- W-@-
           within a magnetic field created by the experimenters, and whe  ther this affects
           its ability to detect ol7jects of varying conductivity.

                     In essence, the primary goal of this effort will be a study of electric fish
                 behavior witi particular reference to:  (a) measurement and characterization of
                 the electric fields produced;  (b) influence of behavior and electric field by
                 an a,rtifically produced field which interfers with the natural field produced by
                 the fish;  and (c) the use of the fishes' electric field for navi4gation, orienta@4
                 tion, object detection and discrimination.
                     This addendum to the original proposal will not effect the total funds, man-
                 power and equipment required nor will it nullify