Fig. 5. Magnetic bearings plotted relative to magnetic north (mN) after housing in outdoor tanks under long-wavelength light (data from Table 1). (A) Magnetic bearings of newts housed under long-wavelength light and tested under full-spectrum light exhibited significant bimodal orientation (black double-headed arrow) along a northeast—southwest magnetic axis (38-218°, r=0.40, P<0.02; Rayleigh test). (B) Newts housed and tested under long-wavelength light exhibited similar bimodal orientation (26-206°, r=0.56, P<0.001). The two distributions were not significantly (NS) different (U²=0.087, P>0.10; Watson U²-test). Triangles at the edges of the two distributions show the home directions for the south-southwest (SSW; circles, filled triangles) and east-southeast (ESE; diamonds, open triangles) groups. Open circles and diamonds represent the magnetic bearings of newts from which natural remanent magnetism (NRM) measurements were later obtained (Brassart et al., 1999).

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