Elevation-driven ecological isolation promotes diversification on Mediterranean islands

Journal article
(Original article)

Publication Details

Author(s): Steinbauer M, Irl S, Beierkuhnlein C
Journal: Acta Oecologica-International Journal of Ecology
Publication year: 2013
Volume: 47
Pages range: 52-56
ISSN: 1146-609X
Language: English


The percentage of single island neo-endemic species (an indicator for evolutionary diversification) was found to be independent of geographic distance to the continent in the case of the Aegean archipelago. It was concluded that speciation is independent of geographic isolation, while evolutionary processes are rather enhanced by habitat heterogeneity. An island's maximum elevation was used as an indicator for habitat heterogeneity. In contrast, we argue that habitat heterogeneity (= habitat diversity, i.e. the richness in different habitats) may be positively related to biotic richness, but a positive effect on speciation is yet to be proven. For any other type of heterogeneity, we propose a precise wording, especially when assessing its effect on speciation processes.

Alternatively, we propose that elevation-driven ecological isolation causes the pattern of endemic species on high-elevation islands. Environmental filtering along an elevational gradient differentiates ecosystems, leading to an increase of isolation with elevation. The reason is that comparable ecosystems are much farther apart than is the case for lowland ecosystems. In addition, ecosystems on neighboring islands or on the continent that may be source regions for colonizing species are small in area in high elevations in comparison with low elevation ecosystems. Consequently, an increased speciation rate resulting in a larger percentage of single island endemic species can be expected for higher elevations on islands and high mountains. Support for this elevation-driven ecological isolation hypothesis comes from other islands in the Mediterranean region (e.g. Crete and Corsica), where an increase of the percentage of endemic species with elevation has been observed. Thus, the assessment of (genetic-) isolation should incorporate the distance to similar habitats instead of simple land-to-land connections.

FAU Authors / FAU Editors

Steinbauer, Manuel Prof. Dr.
Professur für System-Paläobiologie

External institutions
Universität Bayreuth

How to cite

Steinbauer, M., Irl, S., & Beierkuhnlein, C. (2013). Elevation-driven ecological isolation promotes diversification on Mediterranean islands. Acta Oecologica-International Journal of Ecology, 47, 52-56. https://dx.doi.org/10.1016/j.actao.2012.11.004

Steinbauer, Manuel, Severin Irl, and Carl Beierkuhnlein. "Elevation-driven ecological isolation promotes diversification on Mediterranean islands." Acta Oecologica-International Journal of Ecology 47 (2013): 52-56.


Last updated on 2018-06-12 at 13:50