In view of the massive change in the area of distribution of many world biota across classical biogeographical realms, and of the drastic restructuring of the biotic components of numerous ecosystems, the Scientific Committee on Problems of the Environment (SCOPE) decided at its general Assembly in Ottawa, Canada, in 1982 to launch a project on the 'Ecology of Biological Invasions'. Several regional meetings were subsequently organized within the framework of SCOPE, in order to single out the peculiarities of the invasions that took place in each region, the behaviour of their invasive species and the invasibility of their ecosystems. Most noteworthy among such workshops were one in Australia in August 1984, one concerning North America and Hawaii in October 1984, and one dealing with southern Africa in November 1985. A leitmotiv of these workshops was that most of the invasive species to those regions were emanating from Europe and the Mediterranean Basin, inadvertently or intentionally introduced by man. It was therefore considered as a timely endeavour to organize the next regional meeting in relation to this region. The workshop on 'Biological Invasions in Europe and the Mediterranean Basin' was held in Montpellier, France, 21 to 23 May 1986, thanks to the financial support of SCOPE and of the A.W. Mellon Foundation, and the logistic facilities of the Centre National de la Recherche Scientifique (C.N .R.S.).

One. Introduction.- 1. On invading species and invaded ecosystems: the interplay of historical chance and biological necessity.- Two. Plant invasions.- 2. Plant invasions in Central Europe: historical and ecological aspects.- 3. History of the impact of man on the distribution of plant species.- 4. Recent plant invasions in the Circum-Mediterranean region.- 5. The invading weeds within the Western Mediterranean Basin.- 6. Widespread adventive plants in Catalonia.- 7. History and patterns of plant invasion in Northern Africa.- 8. Invasions of adventive plants in Israel.- 9. Man and vegetation in the Mediterranean area during the last 20,000 years.- 10. Plant invasions in Southern Europe from the Paleoecological point of view.- 11. Mediterranean weeds: exchanges of invasive plants between the five Mediterranean regions of the world.- Three. Animal invasions.- 12. The invasion of Northern Europe during the Pleistocene by Mediterranean species of Coleoptera.- 13. Migratory Phenomena in European animal species.- 14. The bean beetle (Acanthoscelides obtectus) and its host, the French bean (Phaseolus vulgaris): a two-way colonization story.- 15. Some recent bird invasions in Europe and the Mediterranean Basin.- 16. Of mice and men.- 17. Invasions by parasites in continental Europe.- 18. Human activities and modification of ichtyofauna of the Mediterranean sea: effect on parasitosis.- 19. Influence of environmental factors on the invasion of molluscs by parasites: with special reference to Europe.- Four. Mechanisms of invasions.- 20. In search of the characteristics of plant invaders.- 21. Biogeographical and physiological aspects of the invasion by Dittrichia (ex Inula) viscosa W. Greuter, a ruderal species in the Mediterranean Basin.- 22. Invaders and disequilibrium.- 23. Species-specific pollination: a help or a limitation to range extension?.- 24. Genetic differentiation in beech (Fagus sylvatica L.) during periods of invasion and regeneration.- 25. Invasion of natural pastures by a cultivated grass (Dactylis glomerata L.) in Galicia, Spain: process and consequence on plant-cattle interactions.- 26. Introduced and cultivated fleshy-fruited plants: consequences of a mutualistic Mediterranean plant-bird system.- 27. Fire as an agent of plant invasion? A case study in the French Mediterranean vegetation.- List of contributors.- Index of Genera and Species.- General index.