Show simple item record

dc.contributor.authorAbdel-Rahman, E.H.
dc.contributor.authorTaylor, P.J.
dc.contributor.authorContrafatto, G.
dc.contributor.authorLamb, J.M.
dc.contributor.authorBloomer, P.
dc.contributor.authorChimimba, C.T.
dc.date.accessioned2010-11-03T12:50:48Z
dc.date.available2010-11-03T12:50:48Z
dc.date.issued2009
dc.identifier.citationAbdel-Rahman, E.H., Taylor, P.J., Contrafatto, G., Lamb, J.M., Bloomer, P. and Chimimba, C.T. (2009). Geometric craniometric analysis of sexual dimorphism and ontogenetic variation: A case study based on two geographically disparate species, Aethomys ineptus from southern Africa and Arvicanthis niloticus from Sudan (Rodentia:Muridae). Mammalian Biology, 74, 361-373en
dc.identifier.urihttp://hdl.handle.net/123456789/757
dc.description.abstractNon-geographic morphometric variation, particularly at the level of sexual dimorphism and ontogenetic (age-related) variation, has been documented in rodents, and useful for establishing whether to analyse sexes separately or together, and for selecting adult specimens for subsequent data recording andanalysis. However, such studies have largely been based on traditional morphometric analyses of linear measurements that mainly focus on overall size, rather than shape-related morphometric variation. Unit-free, landmark/outline-based geometric morphometric analyses are considered to offer a more appropriate tool for assessing shape-related morphometric variation. In this study, we used geometric cranial morphometric analysis to assess the nature and extent of sexual dimorphism and age variation within the Tete veld rat, Aethomysineptus (ThomasandWroughton, 1908) from southern Africa and the African Nilerat, Arvicanthisniloticus (Desmarest, 1822) from Sudan. The results obtained were in turn compared with previously published results based on independent geometric and traditional cranial morphometric data from the same sampled populations examined in the present study. While our geometric morphometric results detected statistically significant sexual dimorphism in cranial shape within Ar. niloticus only, previously published results based on traditional morphometric data failed to detect significant sexual dimorphism within this species. However, similar to previously published traditional morphometric data, our geometric morphometric results detected statistically significant age-related variation in cranial shape and size within both Ae. ineptus and Ar. niloticus, within dividuals of age classes 5 and 6 being considered to represent adults pecimens. Our results highlight the importance of carefully evaluating both size- and shape-related non-geographic morphometric variation prior to the analysis of geographic variation and the delineation of species. Erroneous conclusions of non-geographic variation may have implications in the interpretation of geographic and evolutionary processes that may be responsible for morphological differences at both the inter- and intra-specific levels.en
dc.description.sponsorshipCentre of Excellence for Invasion Biologyen
dc.format.extent796629 bytes
dc.format.mimetypeapplication/pdf
dc.language.isoenen
dc.publisherElsevierGmbH.en
dc.subjectAethomys ineptusen
dc.subjectArvicanthis niloticusen
dc.subjectSexualdimorphism/ontogenetic(age-related)variationen
dc.subjectGeometric/traditional morphometricsen
dc.subjectCraniumen
dc.titleGeometric craniometric analysis of sexual dimorphism and ontogenetic variation: A case study based on two geographically disparate species, Aethomys ineptus from southern Africa and Arvicanthis niloticus from Sudan (Rodentia:Muridae)en
dc.typeJournalArticlesen
dc.cibjournalMammalian Biologyen
dc.cibprojectNAen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record