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Historical processes and environmental factors as determinants of inter-island differences in endemic faunas: the case of the Balearic Islands


Pre-human flora (palynology) and fauna (bird and mammal fossil record) suggest that environmental differences among the Gymnesics and the Pityusics have now been reduced in comparison to the environmental differences at the Pleistocene and Holocene boundary. This environmental homogenization is likely related with human invasion. Historical effects of prehuman differences between Gymnesic and Pityusic Islands are still recognizable on endemic fauna. In contrast, there is no historical effects on interisland similarities using currently breeding birds (as an example of organisms welldispersed and related to vegetation type). We explain the pattern of interisland similarities of endemic fauna as the result of the independent histories among the two islands groups. Contrasting, successive colonizations and extinctions would determine interisland similarities
of breeding birds.
Keywords: Endemic species, extinction, human impact, palaeoenvironment, Balearic Islands.



M. Palmer, G. X. Pons, I. Cambefort and J. A. Alcover (1999)     Journal of Biogeography 26

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