Figure 4
From: Adaptive bill morphology for enhanced tool manipulation in New Caledonian crows
Comparison of shape and internal structure of bills between NCCs (NCC 1, NCC 2), rooks (Rook 1, Rook 2) and large-billed crows (LaC 1, LaC 2).
(A,B) Normalised total bone area along the upper and lower mandibles. (C) Imin/Imax values along the right ramus of the lower mandible between the rostral edge of the Fenestra rostralis and the gonydeal angle. Diamonds on (A) indicate edges of the nasal openings and on (B) indicate the edges of the Fenestra rostralis (at left) and the gonydeal angle (at right).
