کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8959613 1646333 2018 29 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Where did Mikrotia magna originate? Drawing ecogeographical inferences from body mass reconstructions
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فسیل شناسی
پیش نمایش صفحه اول مقاله
Where did Mikrotia magna originate? Drawing ecogeographical inferences from body mass reconstructions
چکیده انگلیسی
Terre Rosse deposits (upper Miocene; Gargano, Italy) have provided fossil remains of an insular fauna among which the genus Mikrotia (Rodentia) stands out. Several paleobiological studies have already been conducted on this genus, but its body mass has not yet been calculated accurately. The aim of the present work is to reconstruct Mikrotia magna's weight, a paramount aspect of organismal biology, especially on islands where mammals modify their size, becoming giants or dwarfs ('island rule'). Our analysis using postcranial elements (femora and humeri) predicts weights ranging from 1300 g to 1900 g (old and young populations, respectively). The presence of a large number of micromammals on the Gargano paleo-island suggests a high interspecific competition for species of the same ecological guild (Prolagus or cricetids were direct competitors of Mikrotia), which may lead to only moderate gigantism, or even body mass reductions in small mammals, following Palkovacs's model. This contrasts with the huge weight of M. magna inferred in this study. In this regard, stratigraphic and taxonomic studies suggest that M. magna was an immigrant from a neighboring island, indicating that this species originated and achieved its enormous size under other selective pressures. A native island with a lower number of competitors, and therefore with less resource limitation than Terre Rosse, might be the principal explanation for such a degree of gigantism.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Geobios - Volume 51, Issue 4, September 2018, Pages 359-366
نویسندگان
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