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Species present in the fossil record may continue to exist at an archaeological site, allowing study that fine-tunes our picture of the ecological past. A large wintering population of Eurasian Crag Martins Ptyonoprogne rupestris (ECM) roosts at the ‘Gorham’s Cave Complex’ UNESCO World Heritage site in Gibraltar, which is best known for its occupation by Neanderthals at times when ECMs were also present. Its complex geomorphology allows the study of use of different micro-sites (caves) within the roost. We used mark-recapture to test whether birds showed fidelity to micro-sites for roosting, and for differences in condition of birds across micro-sites. ECM showed very high fidelity towards micro-sites, within and between years, with > 90% chance of recapture at caves where they were first caught. Condition of birds differed between micro-sites, suggesting differences in roost quality between caves; birds were more likely to be recaptured at the micro-site where birds were in best condition, indicating higher survivorship. Our results demonstrate extremely fine-scale fidelity at the largest roosting site documented for ECM globally. Implications for conservation are discussed. The study provides current knowledge of a bird that has been using these caves since the Pleistocene and more generally on these caves as refuges.

The Mediterranean ribbed limpet Patella ferruginea Gmelin, 1791 is the most endangered marine invertebrate listed in the EU Habitats Directive. A diversity of anthropic pressures have reduced its present-day distribution to a fraction of its former size. Perhaps surprisingly, this highly protected species has successfully established along man-made harbour breakwaters, resulting in serious complications when these structures have required modification or repair, often leading to costly impasses due to the legal status of the species. Attempts to move the limpets to other locations have resulted in unacceptably high mortality rates. This article describes the result of a field experiment where 97 P. ferruginea individuals were transported to a new site, using a technique which involved carefully moving the limpets whilst inactive (during low tide), still attached to their home scars on breakwater boulders. The results of this experiment were significantly positive, with 87% of all translocated limpets still alive 10 mo after the move, a mortality rate which compared favourably with that obtained for the existing control population at the receptor site. We propose that this method could be a practical solution to address the conflicts generated by this endangered species’ preference for harbour constructs. We further propose that this method can be used as a management tool to enhance the species’ survival prospects, by creating ‘stepping stones’ of pockets of reproducing individuals that can connect currently fragmented populations to effect a population recovery of this threatened organism.

We tracked pallid swifts (Apus pallidus brehmorum) from a single breeding colony in Gibraltar over two years. Our results show movement of birds between specific regions within the non-breeding geographical area at specific times of the year. The tracking of a single individual showed remarkable fidelity to the areas visited between years. Furthermore, two pallid swifts tracked over the entire eight-month non-breeding period, while in Africa, gave no indication of coming to land, supporting previous findings of an airborne existence in swifts outside the breeding season. In addition, the crossing of the Sahara Desert to and from breeding grounds is remarkably fast, with one individual crossing it in just over a day. We discuss our findings in the context of bird migration evolutionary strategies.

We compare the Middle Palaeolithic sites of Gibraltar and Zafarraya in southern Iberia. We use birds as indicators of environmental quality and demonstrate huge differences between coastal and inland, mountain, sites separated by less than 150 km. We conclude that the Gibraltar sites represented locations of repeated occupation by Neanderthals over tens of millennia whereas Zafarraya represents a site of sporadic visits for particular prey. This is in response to very different climatic conditions. Our results show how important ecological quality is in understanding Palaeolithic sites and metapopulations and how birds are particularly informative in our understanding of the ecology of such sites.

This paper deals with the so-called Middle Pleistocene revolution, that is, the transition between the Early and Middle Pleistocene between 1.2 and 0.5 million years ago. Our knowledge about biotic changes during this transition has been so far largely based on studies of large mammals. Here we address the issue whether all faunal groups were equally affected. Three datasets have been used: (a) European large mammals present in the Middle and Late Pleistocene, (b) European fossil bird species recorded from the Early, Middle and Late Pleistocene of Europe, and (c) present-day birds currently classified in subfamilies that contain at least one Palaearctic representative species. Each species was allocated to all those geographical areas, climates, habitats in which it is present today; migratory status was also recorded. These datasets serve to undertake a biochronological analysis of mammal and bird groups, thus establishing patterns and processes of extinction and survival at the genus and species levels. The end of the Middle Pleistocene appears to have been a significant boundary in respect of herbivorous mammals, which suffered considerable depletion. In contrast, most genera and species of European birds in the Middle Pleistocene survived into the Late Pleistocene, even to the present day. Furthermore, at least 58% of the Middle–Pleistocene bird species were already present in the Early Pleistocene record. The most successful survivors in the Palaearctic Pleistocene were species from genera that had been the most climatically-tolerant during the late Cenozoic, usually from speciose and widely-distributed genera. We conclude that major transitions in Earth history have leant largely on biochronology and the perceived turnovers of faunas. Boundaries have usually depended heavily on changes to specific taxa of organisms. In this paper we show that what may appear as epic boundaries are largely scale- and taxon-dependent. Their usefulness must therefore be open to question. Here we advocate an individualistic and taxon specific approach in understanding the major ecological changes that have marked the history organisms.

Although hardly applied to human palaeoecology, bird fossils offer a unique opportunity for quantitative studies of the hominin habitat. Here we reconstruct the Homo habitat niche across a large area of the Palaearctic, based on a database of avian fauna for Pleistocene sites. Our results reveal a striking association between Homo and habitat mosaics. A mix of open savannah-type woodland, wetlands and rocky habitats emerges as the predominant combination occupied by Homo across a wide geographical area, from the earliest populations of the Lower Palaeolithic to the latest hunter-gatherer communities of the Upper Palaeolithic. This observation is in keeping with the view that such landscapes have had long standing selective value for hominins.

Using data collected from existing habitats found in the southwestern Iberian Peninsula, and including data collected in the Biological Reserve of the Parque Nacional de Donana, Spain, this study considers the seasonal and inter-annual variability of a thermo-Mediterranean, subhumid, environment and the significance of the presence of surface water in the system. This extant environment is then used together with the fossil record from Gorham's Cave in Gibraltar, where Neanderthals lived, as a proxy for the ecology of the emerged landscape outside the cave.

In this paper, we describe a new method for quantitative reconstruction of bioclimate using a combination of multi-scale ecological datasets of present-day distributions of species with fossil plant and bird data derived from cave deposits of known age. In the specific case of Gorham's Cave, Gibraltar, we make predictions as to the prevailing climate during the Last Glacial Maximum (LGM). Our results indicate only slight variations compared to present-day climate. The present-day climatic regime is encompassed by a wider regime during the LGM. The importance of caves as climate archives is highlighted and our results additionally give focus to the generally underestimated importance of small-scale refugia during glacials.

Homo species were exposed to a new biogeochemical environment when they began to occupy caves. Here we report the first evidence of palaeopollution through geochemical analyses of heavy metals in four renowned archaeological caves of the Iberian Peninsula spanning the last million years of human evolution. Heavy metal contents reached high values due to natural (guano deposition) and anthropogenic factors (e.g. combustion) in restricted cave environments. The earliest anthropogenic pollution evidence is related to Neanderthal hearths from Gorham's Cave (Gibraltar), being one of the first milestones in the so-called “Anthropocene”. According to its heavy metal concentration, these sediments meet the present-day standards of “contaminated soil”. Together with the former, the Gibraltar Vanguard Cave, shows Zn and Cu pollution ubiquitous across highly anthropic levels pointing to these elements as potential proxies for human activities. Pb concentrations in Magdalenian and Bronze age levels at El Pirulejo site can be similarly interpreted. Despite these high pollution levels, the contaminated soils might not have posed a major threat to Homo populations. Altogether, the data presented here indicate a long-term exposure of Homo to these elements, via fires, fumes and their ashes, which could have played certain role in environmental-pollution tolerance, a hitherto neglected influence., SCOPUS: ar.j, info:eu-repo/semantics/published

The evidence for Neanderthal lithic technology is reviewed and summarized for four caves on The Rock of Gibraltar: Vanguard, Beefsteak, Ibex and Gorham’s. Some of the observed patterns in technology are statistically tested including raw material selection, platform preparation, and the use of formal and expedient technological schemas. The main parameters of technological variation are examined through detailed analysis of the Gibraltar cores and comparison with samples from the classic Mousterian sites of Le Moustier and Tabun C. The Gibraltar Mousterian, including the youngest assemblage from Layer IV of Gorham’s Cave, spans the typical Middle Palaeolithic range of variation from radial Levallois to unidirectional and multi-platform flaking schemas, with characteristic emphasis on the former. A diachronic pattern of change in the Gorham’s Cave sequence is documented, with the younger assemblages utilising more localized raw material and less formal flaking procedures. We attribute this change to a reduction in residential mobility as the climate deteriorated during Marine Isotope Stage 3 and the Neanderthal population contracted into a refugium.

Cortés-Sánchez, Miguel et al., Numerous studies along the northern Mediterranean borderland have documented the use of shellfish by Neanderthals but none of these finds are prior to Marine Isotopic Stage 3 (MIS 3). In this paper we present evidence that gathering and consumption of mollusks can now be traced back to the lowest level of the archaeological sequence at Bajondillo Cave (Málaga, Spain), dated during the MIS 6. The paper describes the taxonomical and taphonomical features of the mollusk assemblages from this level Bj19 and briefly touches upon those retrieved in levels Bj18 (MIS 5) and Bj17 (MIS 4), evidencing a continuity of the shellfishing activity that reaches to MIS 3. This evidence is substantiated on 29 datings through radiocarbon, thermoluminescence and U series methods. Obtained dates and paleoenvironmental records from the cave include isotopic, pollen, lithostratigraphic and sedimentological analyses and they are fully coherent with paleoclimate conditions expected for the different stages. We conclude that described use of shellfish resources by Neanderthals (H. neanderthalensis) in Southern Spain started ~150 ka and were almost contemporaneous to Pinnacle Point (South Africa), when shellfishing is first documented in archaic modern humans., The works at Bajondillo Cave and the shellfish harvesting in the Natural Park of Maro-Cerro Gordo were approved by the Junta de Andalucía (Spain). The manuscript was greatly improved by the instructive comments and suggestions of two anonymous reviewers.

Debates surrounding Neanderthals and Anatomically Modern Humans (AMH) tend to focus primarily on discussions of cognitive ability, as exemplified by perceived differences in stone tool technology, behaviour and extinction outcomes. One of the primarily cited differences involves the subsistence strategies practised by these different groups of humans (Brown 2009).

Palaeobotanical (pollen, charcoal) data from Gorham's Cave reveals a diversified landscape in the Gibraltar region during the Middle (c. 32 560-23 780 year BP) and Upper Palaeolithic (c. 18 440-10 880 BP). Inferred vegetation types include oak, pine, juniper, and mixed woodlands and savannahs, grasslands with heaths, heliophytic matorrals, phreatophytic formations (e.g. riverine forests, wetlands), and thermomediterranean coastal scrub. A revision of palaeoecological data suggests that patches of trees persisted even in northern and continental territories of the Iberian Peninsula during the cold stages of OIS3 and OIS2. However, a southern Mediterranean coastal shelf extending from Gibraltar to Málaga, and probably further north up to Murcia, was unique in its combination of thermo-, meso-, and supramediterranean plant and animal species. Given the composition of these assemblages, this shelf and its adjacent mountains represented a crucial reservoir of biodiversity during the Upper Pleistocene. It is within this physiographically complex context with its diversity of resources where the last Neanderthals extraordinarily survived until c. 24 000 BP, that is over 10 000 years later than the disappearance of Neanderthals from elsewhere in temperate Europe. © 2008 Elsevier Ltd. All rights reserved., This research has been funded by the projects CGL-2006-2956-BOS (Ministerio de Educación y Ciencia, Madrid), EU MEDOC Interreg IIIB 2002-02-4, PalaeoMED 1-U-048, and PI-00369/FS/04 and Paleodiversitas Network (Fundación Séneca, Murcia).