Digit 2 of the duck wing has a genuine tip.
A: The pattern of ossification (alizarin red staining) of the last phalanx of digits 1 and 2 is distal (arrows). B: (a) Fresh wing specimen, showing the evident claw at the end of digit 2 (arrow). (b,c) In situ hybridisation showing Bambi expression at the tips of duck digits at E13. (b) Expression is detected in wing digits 1 and 2 (arrowheads). (c) In the leg, Bambi is expressed in all toe tips.