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Abstract: The native or allochthonous nature of certain extant species of the Iberian Peninsula is a matter of some controversy given our lack of knowledge regarding the survival and extinction processes to which they have been subject. The aim of the present work is to provide a review of the current knowledge regarding these processes during the Quaternary. The Middle Pleistocene Transition was a period of noticeable disappearance of Arctotertiary taxa in the Iberian Peninsula, related to the alteration in glacial cyclicity and climate change, including an increase in the severity of glaciations, a reduction in the length of the interglacial periods, and increased dryness during the coldest times. It is difficult to maintain that human activities played any important part in the complete or near-complete disappearance of some taxa during the Quaternary. In the Late Pleistocene and Holocene, however, the extinction of Cedrus, Picea and Carpinus might be related to climate change, competition with other taxa, and anthropogenic disturbances. In contrast, the extreme reduction or even complete disappearance of Platanus or Syringa seems to be due to natural causes alone. The available geological, molecular and palaeobotanical data suggest that some Arctotertiary taxa persisted over long periods of time during the Quaternary in the Iberian Peninsula. Indeed, the fossil record of one important group of taxa, including Castanea, Ceratonia, Carpinus and Juglans, shows its continued presence throughout the Quaternary. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports on analysis of plant macrofossils in aeolian deposits exposed in El Asperillo cliff in the Province of Huelva. A significant find of a large number of macrofossils of Pinus (Pinus pinaster Ait. and Pinus nigra Arnold) makes a major contribution to our understanding of the role of Pine in the Upper Pleistocene landscapes of Iberia. P. pinaster Ait. and P. nigra Arnold, are meso-microthermic species and inhabited valleys excavated in aeolian sediments mainly deposited during OIS 4 and OIS 3 (based on OSL and radiocarbon ages). Their presence in these valleys during the last part of OIS4 and OIS 3 reflects a significant fall in temperature during certain periods of these isotopic stages and helps us better understand the response of coastal dynamics to climate change. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work is to provide a first approach to the evolution of Iberia''s vegetation during the Cenozoic (with the exclusion of the Quaternary). The Palaeogene was floristically defined by Palaeotropical elements forming tropical/subtropical rainforests, mangrove swamps, edaphically-mediated laurophyllous forests and leguminous-sclerophyllous communities. During the Miocene, Iberian landscapes were drastically modified due to geographic and climatic changes (mainly cooling and aridification) changes. Open, steppe-like environments developed towards the interior of the peninsula and Arctotertiary elements invaded mountainous and riparian ecosystems, coexisting with or becoming part of evergreen, broadleaved forests of Palaeotropical species. From the Late Miocene onwards these forests suffered changes due to the extinction of taxa, the impact of environmental change on the survivors, and the perturbations caused by the arrival of further Arctotertiary elements. However, several Palaeotropical taxa overcame the environmental and climatic changes of the Miocene and Pliocene to form a part of the modern flora of the Iberian Peninsula. [Copyright &y& Elsevier]