Geometric morphometric analysis reveals that the shells of male and female siphon whelks Penion chathamensis are the same size and shape

References

• Araya, J.F. (2013) A new species of Aeneator Finlay, 1926 (Mollusca, Gastropoda, Buccinidae) from northern Chile, with comments of the genus and a key to the Chilean species. ZooKeys 257, 89–101. doi:10.3897/zookeys.257.4446
   Google Scholar
• Avaca, M.S., Navarte, M., Martín, P. & Van Der Molen, S. (2013) Shell shape variation in the nassariid Buccinanops globulosus in northern Patagonia. Helgoland Marine Research 67, 567–577. doi:10.1007/s10152-013-0344-5
   Web of Science ®Google Scholar
• Beu, A.G. (2009) Before the ice: biogeography of Antarctic Paleogene molluscan faunas. Palaeogeography, Palaeoclimatology, Palaeoecology 284, 191–226. doi:10.1016/j.palaeo.2009.09.025
   Web of Science ®Google Scholar
• Beu, A.G. & Maxwell, P.A. (1990) Cenozoic Mollusca of New Zealand. New Zealand Geological Survey Bulletin 58.
   Google Scholar
• Bookstein, F.L. (1991) Morphometric tools for landmark data: geometry and biology. Cambridge University Press, Cambridge, UK.
   Google Scholar
• Bookstein, F.L. (1997) Landmark methods for forms without landmarks: morphometrics of group differences in outline shape. Medical Image Analysis 1, 225–243. doi:10.1016/S1361-8415(97)85012-8
   PubMedGoogle Scholar
• Campos, E. (2013) Remarks on the sexual dimorphism and taxonomy of Fabia Dana, 1851 (Crustacea, Brachyura, Pinnotheridae). Zootaxa 3616, 190–200. doi:10.11646/zootaxa.3616.2.7
   PubMed Web of Science ®Google Scholar
• Dell, R.K. (1956) The archibenthal Mollusca of New Zealand. Dominion Museum Bulletin 18.
   Google Scholar
• Dodson, P. (1975) Taxonomic implications of relative growth in lambeosaurine hadrosaurs. Systematic Zoology 24, 37–54. doi: 10.2307/2412696
   Google Scholar
• Fraley, C. & Raftery, A.E. (2002) Model-based clustering, discriminant analysis and density estimation. Journal of the American Statistical Association 97, 611–631. doi: 10.1198/016214502760047131
   Web of Science ®Google Scholar
• Fraley, C. & Raftery, A.E. (2012) mclust version 4 for R: normal mixture modelling for model-based clustering, classification, and density estimation. Technical Report 597, University of Washington.
   Google Scholar
• Frassinetti, D.C. (2000) Upper Pliocene marine mollusks from Guafo Island, southern Chile. Part II. Gastropoda. Boletin del Museo Nacional de Historia Natural, Chile 49, 131–161.
   Google Scholar
• Goodfriend, G.A. (1986) Variation in land-snail shell form and size and its causes: a review. Systematic Zoology 35, 204–223. doi: 10.2307/2413431
   Google Scholar
• Gunz, P., Mitteroecker, P. & Bookstein, F.L. (2005) Semilandmark in three dimensions. In: Slice, D.E. (Ed.), Modern morphometrics in physical anthropology. Kluwer Academic/Plenum, New York, USA, pp. 73–98.
   Google Scholar
• Harasewych, M.G. & Kantor, Y.I. (1999) A revision of the Antarctica genus Chlanidota (Gastropoda: Neogastropoda: Buccinulidae). Proceedings of the Biological Society of Washington 112, 253–302.
   Web of Science ®Google Scholar
• Hayashi, S. (2005) The molecular phylogeny of the Buccinidae (Caenogastropoda: Neogastropoda) as inferred from the complete mitochondrial 16S rRNA gene sequences of selected representatives. Molluscan Research 25, 85–98.
   Google Scholar
• Hills, S.F.K., Crampton, J.S., Trewick, S.A. & Morgan-Richards, M. (2012) DNA and morphology unite two species and 10 million year old fossils. PLOS ONE 7, e52083. doi:10.1371/journal.pone.0052083
   PubMed Web of Science ®Google Scholar
• Huynen, L., Millar, C.D., Scofield, R.P. & Lambert, D.M. (2003) Nuclear DNA sequences detect species limits in ancient moa. Nature 425, 175–178. doi:10.1038/nature01838
   PubMed Web of Science ®Google Scholar
• Iguchi, A., Ito, H., Ueno, M., Maeda, T., Minami, T. & Hayashi, I. (2005) Morphological analysis of a deep-sea whelk Buccinum tsubai in the Sea of Japan. Fisheries Science 71, 823–828. doi:10.1111/j.1444-2906.2005.01033.x
   Web of Science ®Google Scholar
• Jackson, D.A. (1993) Stopping rules in principal components analysis: a comparison of heuristical and statistical approaches. Ecology 74, 2204–2214. doi:10.2307/1939574
   Web of Science ®Google Scholar
• Jones, D.T. (1938) The supramarginal ridge in certain American snails. The Ohio Journal of Science 38, 125–135.
   Google Scholar
• Kantor, Y.I. (2003) Comparative anatomy of the stomach of Buccinoidea (Neogastropoda). Journal of Molluscan Studies 69, 203–220. doi:10.1093/mollus/69.3.203
   Web of Science ®Google Scholar
• Kenchington, E.L. & Glass, A. (1998) Local adaptation and sexual dimorphism in the waved whelk (Buccinum undatum) in Atlantic Nova Scotia with application to fisheries management. Canadian Technical Report of Fisheries and Aquatic Sciences 2237.
   Google Scholar
• Khorozyan, I. (2014) Morphological variation and sexual dimorphism of the common leopard (Panthera pardus) in the Middle East and their implications for species taxonomy and conservation. Mammalian Biology 79, 398–405. doi:10.1016/j.mambio.2014.07.004
   Web of Science ®Google Scholar
• Kimbel, W.H. & White, T.D. (1988) Variation, sexual dimorphism and the taxonomy of Austalopithecus. In: Grine, F.E. (Ed.), Evolutionary History of the “Robust” Australopithecines. Transaction Publishers, New York, NY, USA, pp. 175–192.
   Google Scholar
• Klingenberg, C.P. (2011) MorphoJ: an integrated software package for geometric morphometrics. Molecular Ecology Resources 11, 353–357. doi:10.1111/j.1755-0998.2010.02924.x
   PubMed Web of Science ®Google Scholar
• Kurata, K. & Kikuchi, E. (2000) Comparisons of life-history traits and sexual dimorphism between Assiminea japonica and Angustassiminea castanea (Gastropoda: Assimineidae). Journal of Molluscan Studies 66, 177–196. doi: 10.1093/mollus/66.2.177
   Web of Science ®Google Scholar
• Mahilum, J.J.M. & Demayo, C.G. (2014) Sexual dimorphism on the shell shape of Pomacea canaliculata Lamarck thriving in lakes using the geometric morphometric approach. International Journal of Bioscience, Biochemistry and Bioinformatics 4, 284–289. doi:10.7763/IJBBB.2014.V4.357
   Google Scholar
• Minton, R.L. & Wang, L.L. (2011) Evidence of sexual shape dimorphism in Viviparus (Gastropoda: Viviparidae). Journal of Molluscan Studies 77, 315–317. doi:10.1093/mollus/eyr014
   Web of Science ®Google Scholar
• Mitteroecker, P., Gunz, P., Windhager, S. & Schaefer, K. (2013) A brief review of shape, form, and allometry in geometric morphometrics, with applications to human facial morphology. Hystrix, the Italian Journal of Mammalogy 24, 59–66. doi:10.4404/hystrix-24.1-6369
   Web of Science ®Google Scholar
• Monteiro, L.R. (2013) Morphometrics and the comparative method: studying the evolution of biological shape. Hystrix, the Italian Journal of Mammalogy 24, 25–32. doi:10.4404/hystrix-24.1-6282
   Web of Science ®Google Scholar
• Nielsen, S.N. (2003) Die marinen Gastropoden (exklusive Heterostropha) aus dem Miozän von Zentralchile. Unpublished PhD Thesis. University of Hamburg, Hamburg, Germany.
   Google Scholar
• Oksanen, J., Blachet, F.G., Kindt, R., Legendre, P., Minchin, P.R., O’Hara, R.B., Simpson, G.L., Solymos, P., Stevens, M.H.H. & Wagner, H. (2015) vegan: community Ecology Package. R package version 2.2-1. Available online at http://CRAN.R-project.org/package=vegan [Accessed on 10 July 2016.]
   Google Scholar
• Pastorino, G. (2007) Sexual dimorphism in shells of the southwestern Atlantic gastropod Olivella plata (Ihering, 1908) (Gastropoda: Olividae). Journal of Molluscan Studies 73, 283–285. doi:10.1093/mollus/eym024
   Web of Science ®Google Scholar
• Perez, S.I., Bernal, V. & Gonzalez, P.N. (2006) Differences between sliding semi-landmark methods in geometric morphometrics, with an application to human craniofacial and dental variation. Journal of Anatomy 208, 769–784. doi:10.1111/j.1469-7580.2006.00576.x
   PubMed Web of Science ®Google Scholar
• Polly, P.D., Lawing, A.M., Fabré, A., Goswami, A. (2013) Phylogenetic principal components analysis and geometric morphometrics. Hystrix, the Italian Journal of Mammalogy 24, 33–41. doi:10.4404/hystrix-24.1-6383
   Web of Science ®Google Scholar
• Ponder, W.F. (1971) A review of the New Zealand recent and fossil species of Buccinulum Deshayes (Mollusca: Neogastropoda: Buccinidae). Journal of the Royal Society of New Zealand 1, 231–283. doi: 10.1080/03036758.1971.10423314
   Google Scholar
• Ponder, W.F. (1973) A review of the Australian species of Penion Fischer (Neogastropoda: Buccinidae). Journal of the Malacological Society of Australia 2, 401–428.
   Google Scholar
• Powell, A.W.B. (1927) Variation of the molluscan genus Verconella with descriptions of new Recent species. Transactions of the New Zealand Institute 57, 549–558.
   Google Scholar
• Powell, A.W.B. (1979) New Zealand Mollusca. Marine, land and freshwater shells. Collins, Auckland, New Zealand.
   Google Scholar
• R Core Team. (2014) R: a language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. Available online at http://www.R-project.org/ [Accessed on 7 July 2016.]
   Google Scholar
• Reid, D.G., Rumbak, E. & Thomas, R.H. (1996) DNA, morphology and fossils: phylogeny and evolutionary rates of the gastropod genus Littorina. Philosophical Transactions of the Royal Society B: Biological Sciences 351, 877–895. doi: 10.1098/rstb.1996.0082
   PubMed Web of Science ®Google Scholar
• Reskind, J. (1965) The taxonomic problem of sexual -dimorphism in spiders and a synonymy in Myrmecotypus (Aranae, Clubionidae). Psyche: A Journal of Entomology 72, 279–281. doi: 10.1155/1965/17894
   Google Scholar
• Rohlf, F.J. (2013) tpsUtil 1.58 and tpsDig 2.17. Department of Ecology and Evolution, State University of New York. Available online at http://life.bio.sunysb.edu/morph/ [Accessed on 7 July 2016.]
   Google Scholar
• Rosenthal, R.J. (1970) Observations on the reproductive biology of the Kellet’s whelk, Kelletia kelletii. The Veliger 12, 319–324.
   Google Scholar
• Schilthuizen, M. & Haase, M. (2010) Disentangling true shape differences and experimenter bias: are dextral and sinistral snail shells exact mirror images? Journal of Zoology 282, 191–200. doi:10.1111/j.1469-7998.2010.00729.x
   PubMed Web of Science ®Google Scholar
• Sheets, H.D. (2014) Integrated Morphometrics Package (IMP) 8. Availabel online at http://www3.canisius.edu/~sheets/morphsoft.html [Accessed on 7 July 2016.]
   Google Scholar
• Simone, L.R. (1996) Anatomy and systematics of Buccinanops gradatus (Deshayes, 1844) and Buccinanops monilferus (Kiener, 1834) (Neogastropoda, Muricoidea) from the southeastern coast of Brazil. Malacologia 38, 87–102.
   Web of Science ®Google Scholar
• Smith, U.E., Hendricks, J.R. (2013) Geometric morphometric character suites as phylogenetic data: extracting phylogenetic signal from gastropod shells. Systematic Biology 62, 366–385. doi:10.1093/sysbio/syt002
   PubMed Web of Science ®Google Scholar
• Son, M.H. & Hughes, R.N. (2000) Sexual dimorphism of Nucella lapillus (Gastropoda: Muricidae) in North Wales, UK. Journal of Molluscan Studies 66, 489–498. doi:10.1093/mollus/66.4.489
   Web of Science ®Google Scholar
• Ten Hallers-Tjabbes, C.C.T., Kemp, J.F. & Boon, J.P. (1994) Imposex in whelks (Buccinum undatum) from the open North Sea: relation to shipping traffic intensities. Marine Pollution Bulletin 28, 311–313. doi: 10.1016/0025-326X(94)90156-2
   Web of Science ®Google Scholar
• Tokeshi, M., Ota, N. & Kawai, T. (2000) A comparative study of morphometry in shell-bearing molluscs. Journal of Zoology 251, 31–38. doi:10.1111/j.1469-7998.2000.tb00590.x
   Web of Science ®Google Scholar
• Underhill, D.M. & Illiev, I.D. (2014) The mycobiota: interactions between commensal fungi and the host immune system. Nature Reviews Immunology 14, 405–416. doi:10.1038/nri3684
   PubMed Web of Science ®Google Scholar
• Venables, W.N. & Ripley, B.D. (2002) Modern applied statistics with S. Fourth Edition. Springer, New York, USA.
   Google Scholar
• Webster, M. & Sheets, H.D. (2010) A practical introduction to landmark-based geometric morphometrics. Quantitative Methods in Paleobiology 16, 163–188.
   Google Scholar
• Zelditch, M.L., Swiderski, D.L., Sheets, H.D. & Fink, W.L. (2004) Geometric morphometrics for biologists: a primer. Elsevier Academic Press, London, UK.
   Google Scholar