Three sedimentary sequences from the southeastern littoral of the Iberian Peninsula have been palynologically studied. The results obtained show that during the Holocene no significant forest cover existed in the studied area, so that the different phases identified mainly show an alternation of shrub formations and steppe communities probably determined by limitations that are fundamentally bioclimatic. Highest values of arboreal pollen at the bottom of the San Rafael sequence would correspond to an older period, when the area appears to be dominated by shrub communities with a high proportion of wild olive, whereas at the beginnings of the Holocene it is dominated by steppe formations. Between 7000 and 4500 yr BP the Holocene optimum is recorded, with a significant degree of vegetational cover. This period ends abruptly with a radical transform ation of the landscape that reflects the establishment of the steppe conditions that persist today, which lead to the marginalization of the maquis and the impact of intense erosion processes on a gradually deforested countryside.

Aim To locate glacial refugia of thermophilous plant species in Spain. Location Two south‐eastern Spanish Neanderthal man sites in Murcia; namely, the inland Cueva Negra del Estrecho del Río Quípar and the coastal Sima de las Palomas del Cabezo Gordo. Methods We use pollen found in cave sediments as a source of palaeobotanical and palaeoecological information. The findings are discussed with regard both to animal remains from both sites, and also to other refugia in south‐eastern Spain and elsewhere in the Iberian Peninsula. Results Both sequences show persistence of abundant mesothermophilous trees during the last glacial stage, suggesting both localities were reservoirs of phytodiversity and woodland species. At both sites, deciduous and evergreen oaks are the most abundant components, followed by a wide variety of deciduous trees and sclerophyllous shrubs, including Ibero‐North African xerothermic scrub near the coast. Conclusions Incomplete information underlies a common misapprehension that Iberian glacial refugia were confined to southernmost parts of the peninsula. A rather different picture of Quaternary refugia emerges from consideration of pollen sequences from caves (and other inputs such as macroscopic charcoal, spatial genetic structure of present‐day populations, faunal remains, and present‐day distribution of thermophilous species). This picture offers a view of numerous viable areas for woodland species in southern Spain, in addition to others in the mountain ranges, both in continental central Spain and those of northern Spain: these stretch from the Mediterranean coast of Catalonia to the westernmost extent of the Bay of Biscay.

Four pollen diagrams from Minorca (Balearic Islands) have been correlated with other previously studied sequences from Majorca and Minorca to define a Holocene landscape sequence for the region from 8000 yr B.P. to the present. The lower part of the pollen diagrams reflects a climatic phase with more rain and less-marked seasonality than today. Significant quantities of Corylus, Buxus, and mesophilous taxa are found. In the middle part, between 5000 and 4000 yr B.P., a strong change is recorded in composition and structure of the vegetational landscape, with vegetation appearing that was adapted to Mediterranean conditions. This episode coincided with the first human colonization of the island and also with a widespread climatic change in the western Mediterranean region. The change in taxa was complex and some sclerophyllous taxa such Olea played an important role in the transformation of the landscape physiognomy from the mid-Holocene until the present. Although human activities have removed much of the Mediterranean vegetation on the Balearic Islands, it seems clear that the changes have been brought about, in part, by increasing dryness.

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Myotragus balearicus Bate 1909 is an artiodactyl Caprinae endemic to the Balearic Islands which became extinct more than 4000 years ago. Coprolites produced by this species have been collected from the excavation of Holocene cave sediments in Cova Estreta (Serra de Tramuntana, Mallorca). The pollen content of several samples of coprolites has been studied in order to determine the diet of Myotragus. Myotragus balearicus from Cova Estreta was a browser, and consumed huge amounts of box, Buxus balearica, a plant known for its high content of steroidal alkaloids. The coprolites are very fine textured, probably due to the result of a very efficient digestive process.

AbstraetAn analysis of sedimentation rates during the Holocene in estuaries in the southwestern coast of the Iberian Peninsula using depth/age diagrams reveals the existence of two distinct phases. The first, between ca. 10,000 and 6500 Cal BP, still in the transgressive phase, yields values of sedimentation rates of 5 mm/yr. The second phase extends after the maximum transgressive (ca. 6500 Cal BP) until the present, with sedimentation rates of 1.5-2 mm/yr. These results support the idea that marine sedimentation began during the transgressive phase and continued during the highstand phase, far beyond the time of the transgressive maximum, as postulated in some previous papers. i

Most unsuccessful palynological work is never published. As a consequence, pollen analysts waste time re-processing sterile sediments, and the available literature exhibits a uniformly positive record of success in pollen extraction. Here we report failures with Quaternary pollen analyses in the Iberian Peninsula; that is, case studies where it was not possible to extract palynomorphs for pollen counting. Both totally sterile and partially sterile sites are considered. Sites and perspectives for future studies are suggested. The majority of the failed studies are openair archaeological and palaeontological sites, caves and rockshelters, but there are prominent cases of success. Peat bogs have provided positive results, but only with sequences formed under continuous sedimentation processes in marshy environments. Lakes are often successful sites, but a multi-core strategy, following the facies change along a transect from the shore to the depositional centre, is recommended for saline lacustrine deposits, salt marshes and lagoons, especially when there is evidence of temporary desiccation. Cave and rockshelter infills should be considered case-by-case, and these sites definitely require a palyno-taphonomical approach to post-depositional processes. Indurated deposits are sometimes surprising in their high pollen concentration, but one must be prepared for sterility. Coprolites have been insufficiently exploited, and offer a great potential, especially those of Pleistocene Crocuta. This article shows that venturing into sediments assumed a priori to be 'difficult', like fluvial terraces, slope deposits, speleothems, cave travertines, and palaeosols, may nevertheless be successful. A