Figure 1
Forecrown plumage (1) coloration was scored in: A) Pogoniulus
pusillus pusillus ; and B) Pogoniulus chrysoconus extoni . We also
scored: (2) supercilium; and (3) wing bar extent of yellow over black,
from photographs, as shown of C) P. p. pusillus and D) P.
c. extoni from allopatric populations. Samples, photographs scored and
forecrown feathers were obtained from individuals that were
phenotypically red-fronted (red circles) and yellow-fronted (yellow
circles) across the contact zone (green line) in southern Africa (E).