Table 3

Orientation of 12 birds recorded under UV light of two intensities

373 nm UV

Intensity
 axr
 axb
 med rb
 αN
 rN
8·1015 qu/s m2
 47
 50
 0.76
 89°–269°
 0.50*
0.8·1015 qu/s m2
 11
 8
 0.95
 8°
 0.96***

axr, axb, percentage of axial recordings and axial mean vectors of birds, respectively (both as defined in text); med rb, median vector length of the individual birds, representing the intraindividual variance; αN, rN, grand mean vector or axis (non-significant data in parentheses), with asterisks at rN indicating significance by the Rayleigh test, see Table 1

Wiltschko et al. Frontiers in Zoology 2007 4:5   doi:10.1186/1742-9994-4-5