Journal
BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY
Volume 104, Issue 4, Pages 756-769Publisher
OXFORD UNIV PRESS
DOI: 10.1111/j.1095-8312.2011.01748.x
Keywords
continental island; geographic variation; land snail; spire index
Categories
Funding
- Woodside Energy Ltd, Rio Tinto
- University of Western Australia School of Animal Biology
- Department of Environment and Conservation, Western Australia
Ask authors/readers for more resources
On Rosemary Island, a small continental island (11 km(2)) in the Dampier Archipelago, Western Australia, snails of the genus Rhagada have extremely diverse morphologies. Their shells vary remarkably in size and shape, with the latter ranging from globose to keeled-flat, spanning the range of variation in the entire genus. Based primarily on variation in shell morphology, five distinct species are currently recognized. However, a study of 103 populations has revealed continuity of shell form within a very closely-related group. A phylogenetic analysis of specimens from Rosemary Island, and other islands in the Dampier Archipelago, indicates that much of the morphological variation has evolved on the island, from within a monophyletic group. Within the island, snails with distinct shell morphologies could not be distinguished based on variation in mitochondrial DNA or their reproductive anatomy. The shell variation is geographically structured over a very fine scale, with clines linking the extreme forms over distances less than 200 m. Although there is no evidence that the different forms have evolved in isolation or as a consequence of drift, there is a strong association between keeled-flat shells and rocky habitats, suggesting that shell shape may be of adaptive significance. (C) 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104, 756-769.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available