Fig. 5
From: Diversifying Coevolution between Crossbills and Conifers
The relationship between relative tree fitness because of seed predation by crossbills and scale thickness in the western Pyrenees (n = 65 trees; from Mezquida and Benkman in press). The solid curve represents a cubic spline, and the dashed curves represent ± one SE based on 50 bootstrap replicates. The drawings of the two cones represent the variation in scale thickness from thinner scales on the left to thicker scales on the right