Publication Type: | Journal Article |
Year of Publication: | 1991 |
Authors: | Louis, VLSt., Barlow, JC |
Journal: | The Wilson Bulletin |
Volume: | 103 |
Issue: | 1 |
Date Published: | 1991 |
ISBN Number: | 00435643 |
Keywords: | Passer, Passer montanus, Passeridae, Salicipasser, Salicipasser montanus |
Abstract: | Birds introduced into new environments by humans provide opportunity to assess microevolutionary change in morphology. The skeletal morphologies of introduced North American and ancestral German populations of the Eurasian Tree Sparrow (Passer montanus) were compared to assess: (1) the extent of morphometric differentiation between the introduced and ancestral populations, and (2) whether the introduced populations, which exhibited a decrease in genetic variability relative to the German population, display any such differences in morphometric variability. Sexual dimorphism in certain skeletal characters in P. montanus is interpreted to be a result of intraspecific interactions among males and adverse climatic conditions on both sexes. The smaller body size of North American P. montanus is thought to result either from interspecific interactions and/or flight habits different from their ancestral counterparts. Significant differences in bill morphology are found between German and North American P. montanus, which we believe reflect differences in diet. The North American population shows no significant decrease in intrinsic morphometric variation corresponding to the decrease in genetic variation demonstrated in comparison to German birds. |
URL: | http://www.jstor.org/stable/4162965 |
Short Title: | The Wilson Bulletin |
Taxonomic name: