We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
A geometric morphometric appraisal of beak shape in Darwin’s finches.
- Authors
FOSTER, D. J.; PODOS, J.; HENDRY, A. P.
- Abstract
Beak size and shape in Darwin’s finches have traditionally been quantified using a few univariate measurements (length, depth, width). Here we show the improved inferential resolution of geometric morphometric methods, as applied to three hierarchical levels: (i) among seven species on Santa Cruz Island, (ii) among different sites on Santa Cruz for a single species ( Geospiza fortis), and (iii) between large and small beak size morphs of G. fortis at one site (El Garrapatero). Our results support previous studies in finding an axis of shape variation (long/shallow/pointy vs. short/deep/blunt) that separates many of the species. We also detect additional differences among species in the relative sizes and positions of the upper and lower mandibles and in curvature of the mandibles. Small-scale, but potentially relevant, shape variation was also detected among G. fortis from different sites and between sympatric beak size morphs. These results suggest that adaptation to different resources might contribute to diversification on a single island.
- Subjects
GALAPAGOS Islands; SONGBIRDS; BEAKS; MANDIBLE; ANATOMY; ANIMAL populations
- Publication
Journal of Evolutionary Biology, 2008, Vol 21, Issue 1, p263
- ISSN
1010-061X
- Publication type
Article
- DOI
10.1111/j.1420-9101.2007.01449.x