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Species mapping methods play a central role in biogeographical questions, as they may generate a domino effect on further works based on species distribution. In light of the massive recent increase in the availability of online occurrence data, we highlight the strengths and limitations of the mapping methods most widely used to display the geographic distribution of plants, namely geographic range maps and occurrence record maps. We use the modern distribution of the genus Arbutus in western Eurasia, North Africa, and Macaronesia, for which no occurrence record map has been published yet, to discuss critical issues in data collection and representation. The occurrence record map of A. unedo, A. andrachne, A. canariensis, and A. pavarii shows how well this mapping method captures the details of peripheral and isolated stands as well as the variability of population density. A number of biogeographical issues are addressed by this approach, including the determination of the chorological centre of gravity in relation to historical dynamics, genetic patterns in relation to range porosity, and the autochthony status of marginal stands. These issues constitute the necessary foundation for additional palaeobotanical research and ecological modelling to investigate the past-to-future dynamics of Arbutus and other species of the Mediterranean-Atlantic area.

The Nile Dalta was originally flooded during seasons of high water in the Nile but today it is drained and cultivated. The lower parts have been transformed into fish ponds. Remnants of the original vegetation can be seen at Lake Burullus near the coast. We distinguished four original vegetation zones from south to north: a) reeds dominated by Phragmites australis, b) salt marshes, c) shallow lagoon lakes and d) coastal dunes. 'Tells' or 'koms' denote in the Middle East low hills containing remains of abandoned villages. The Nile Delta is dotted with tells which are protected by law. Due to the very dry climate their clayey soil is salty and salt precipitates on the surface. This solonchak soil is suitable only to salt plants, otherwise found on seashores, e.g., Halocnemum strobilaceum, Sarcocornia fruticosa, Suaeda spp. and Kali turgidum. These have been considered as weeds on the tells, but we consider them as immigrants from the saltmarshes further north. Before the Nile was regulated, there should have been an influx southwards of saltwater during periods of low river water. The salt tolerant species then migrated southwards and found suitable habitats on the tells. The original state of the delta with its seasonal variation in water level was suitable for a Neolithic population. There was plenty of hunting game, including wild boars.and resident and migrating birds. The reed was a readily available and plentiful source of fuel. Cyperus papyrus is now absent fro the delta but was once important there. it was used not only for making paper but also as food. Herodotus described the delta as a rich country with plenty of resources.

Questions European native laurophyllous species are interesting for their biogeography and evolutionary history, as well as for their responses to global changes. We identified Italian native laurophylls on the basis of morphology, biogeographical history and ecological niche to study whether these species are in equilibrium with the present-day climate. Furthermore, we localized Quaternary refugia and areas of potential spread of native laurophylls using distribution patterns of realized and potential aggregations of native laurophylls, respectively. Location Italy. Methods We extracted data for 17 087 forest plots from a phytosociological database. Detrended Correspondence Analysis of these plots with overlay of climatic and environmental variables was performed to identify native laurophylls, i.e., evergreen broad-leaved species of late Tertiary radiation, occupying a warm and humid niche. Potential ranges of laurophylls were calculated using Beals' index of sociological favourability. The realized/potential range-size ratio was calculated for each single laurophyll to understand whether it is in equilibrium with the present-day climate. Distribution patterns of realized and potential aggregations of laurophylls were mapped. Results Ordination analysis provided a selection of 11 species as Italian native laurophylls. Most of them occupied less than half of their estimated potential range. Realized aggregations richest in native laurophylls were localized in the central Apennines. However, the Italian forests showed high potential for native laurophylls with the richest potential aggregations in the whole Apennines and in the southern Alps. Conclusions Most of the Italian native laurophylls showed non-equilibrium with the current climate, suggesting that late-Quaternary events could better explain their present-day distribution than on-going climate change. Furthermore, their refugia in central Italy suggest the persistence in sites with temperate climate during Q