Patterns of diversification in mediterranean oat grasses ("Poaceae: Aveneae")
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Martin Röser [1]
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[1] University of Leipzig
University of Leipzig
Kreisfreie Stadt Leipzig, Alemania
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- Localización: Lagascalia, ISSN 0210-7708, Vol. 19, Nº 1-2, 1997, págs. 101-120
- Idioma: español
- Enlaces
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Resumen
Several genera of the Aveneae have a centre of species diversity in the Mediterranean Region and its vicinity. Based originally on the life form of a perennial herb, numerous edaphically, climatically and altitudinally differently adapted species complexes have evolved in the area. Most of these complexes show west-east disjunctions and contain geographically, sometimes even edaphically vicarious taxa with complementary distribution. A transition from mesomorphic to xeromorphic habit occurred independently in different genera and species groups. The correlations of this process with polyploidization, geographical distribution and wide or narrow ecological amplitudes are critically examined. The transition to an annual life form is regarded as a further way of adaptation to Mediterranean type climate which permitted to expand specifically in unstable, ephemeral habitats.
