Thinking Lampedusa: border construction,the spectacle of bare life and the productivity of migrants

This article interrogates the relationship between the Italian island of Lampedusa and trans-Mediterranean migration. It explores how the construction of Lampedusa as a border zone has been implicated in the rise and fall in numbers of migrants reaching the island's shores over the last two decades. It proceeds to consider the appropriateness of interpreting death and detention on Lampedusa in terms of ‘bare life’. While acknowledging how Giorgio Agamben's formulation of bare life has been problematized in relation to irregular migration and taking into account the frequent acts of migrants' political agency on the island itself, it is argued that the transformation of Lampedusa by the media and political establishment into a spectacle of bare life is not only instrumental to the functioning of migration management at Europe's southern border but is also constitutive of the subordinate position of migrants in Italian society and its labour market.     

Macaca nigra on Bacan Island,Indonesia: Its morphology,distribution, and present habitat

We studied the monkeys inhabiting Bacan Island on the Maluku Archipelago, Indonesia. We compared them morphologically with Sulawesi black macaques (Macaca nigra).We also assessed their distribution on the island and on neighboring islands and the influence of human activity on them. We found that the Bacan black macaques are essentially similar to Sulawesi macaques; the variations in each locality are comparable. The monkeys probably inhabit the whole island or, at least, the lower forest thereon. Human activities — cultivation, logging, catching and killing monkeys — have not much affected their population. Thus they constitute a good stock of Macaca nigra,though the main population in Sulawesi is endangered.     

Effect of environmental factors on the abundance variations of two native rodents in agricultural systems of Buenos Aires,Argentina

Our aim was to assess the effect of environmental factors on short temporal abundance variations of the two most abundant native rodents of agricultural agroecosystems, Akodon azarae and Calomys laucha. We conducted a 3‐year longitudinal sampling of rodents, and recorded meteorological data such as temperature and precipitation, predation rate by Leopardus geoffroyi, Tyto furcata and Athene cunicularia, vegetation cover and height, characteristics of cropfields and their borders. The effect of these factors on rodent abundance was evaluated through generalized linear mixed models. Abundance variations of both rodent species were explained by characteristics of both cropfields and their borders. At the studied temporal scale, meteorological variables did not have a direct effect on abundance variations, but probably influenced through vegetation characteristics and were expressed in seasonal variations. For A. azarae there was also an effect of predation by L. geoffroyi (positive) and T. furcata (negative), while predation by A. cunicularia did not contribute to explain abundance variations of any species.     

Long-term variations in rodent abundance in a rural landscape of the Pampas, Argentina

The goal of this study was to analyze the variations in abundance of rodent communities over the last 24 years in a rural area, and their relation to possible changes in climatic variables and land use. The principal change in the area observed along the study period was an increase in the area covered by soybean. The habitats studied were crop fields and borders. The total abundance of rodents did not show a significant trend of variation over time in crop fields while in borders the abundance in autumn–winter (A–W) showed a significant trend to decrease over time. The different rodent species showed a differential response over time. While Calomys laucha and C. musculinus showed a decrease between the period before and after the soybean expansion, Akodon azarae did not change its abundance over time. The mean minimum temperature increased over time while the number of days with frost decreased. Total rodent abundance in A–W was positively associated with the cumulated precipitation of the previous spring–summer period and negatively with the cumulated precipitation of the same period. We conclude that rodent abundance variations in crop fields and borders of the study area are influenced by precipitation, but the observed trends of variation over time are better explained by changes in agricultural practices than by meteorological variables.     

Song divergence at the edge of Amazonia: an empirical test of the peripatric speciation model

The evolutionary divergence of mating signals provides a powerful basis for animal speciation. Divergence in sympatry strengthens reproductive isolation, and divergence in allopatry can reduce or eliminate gene flow between populations on secondary contact. In birds, the first of these processes has empirical support, but the second remains largely hypothetical. This is perhaps because most studies have focused on oscine passerines, whose song learning ability may reduce the influence of vocalizations in reproductive isolation. In suboscine passerines, the role of learning in song development is thought to be minimal, and the resultant signals are relatively fixed. To investigate the role of song in the early stages of peripatric speciation, we therefore studied a suboscine, the chestnut‐tailed antbird Myrmeciza hemimelaena. We recorded male songs in a natural forest island (isolated for < 3000 years) at the southern fringe of Amazonia, and at two nearby sites in continuous forest. A previous study found the isolated population to be weakly differentiated genetically from the ancestral population suggesting that peripatric speciation was underway. In support of this, although we detected minor but significant differences in song structure between each site, the most divergent songs were those of island birds. On simulating secondary contact using playback, we found that pairs from the forest island responded more strongly to island (i.e. local) songs than to those from both non‐island sites, and vice versa. This pattern was not observed in pairs from one non‐island site, which responded with equal strength to local songs and songs from the other non‐island site. Island females were more likely to approach and sing after hearing local male songs, rather than songs from the non‐island populations, and vice versa; non‐island females did not appear to discriminate between local songs and those from the other non‐island site. These findings are consistent with the idea that vocal divergence arising in small populations at the edge of Amazonia may result in partial reproductive isolation when contact is resumed. They also suggest the possibility that song divergence in peripatry may, after much longer time‐frames, act as a barrier to gene flow in suboscines, perhaps because of an inability to learn or recognize divergent songs on secondary contact. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society, 2007, 90 , 173–188.     

Genetic variation of pantropical Terminalia catappa plants with sea‐drifted seeds in the Bonin Islands: suggestions for transplantation guidelines

The Bonin Islands are endowed with endemic species. However, these species are at risk of extinction because of the exuberance of invasive alien plants. Therefore, native plant species should be revegetated after eradicating alien plants. We investigated the genetic variation of Terminalia catappa populations in the Bonin Islands by using nuclear (n) microsatellites (simple sequence repeats [SSRs]) and chloroplast (cp) DNA. No significant differences were observed in the genetic diversity of nSSRs among 22 populations. However, recent bottlenecks were detected in three populations on the Chichijima Island group. nSSR variation and cpDNA haplotypes suggested the presence of two genetically distinct groups in the Mukojima and Chichijima Island groups and the Hahajima Island group. A similar genetic structure was observed in plants and animals in the Bonin Islands. Populations on the three islands, which were separated from other islands in each island group when the water depth was 50‐m lower than the present level, were dominated by unique nSSRs clusters, suggesting that historical changes in island connections during the Pleistocene era affected genetic substructuring. These results suggested that different factors contributed to the genetic structure of T. catappa on different geographic scales. At the whole‐island level, the genetic structure was determined by long‐distance seed dispersal by ocean currents. At the island‐group level, the genetic structure was determined by historical changes in island connections caused by changes in the sea level due to glacial–interglacial transition. These findings would help in establishing transplantation zone borders for revegetating T. catappa on the Bonin Islands.     

Population pressure,labor availability,and agricultural disintensification: The decline of farming on Rusinga Island,Kenya

Despite a steady increase in population since the 1930s, farmers on Rusinga Island in Kenya have abandoned many traditional intensive agricultural practices, including the construction of hillside terraces. At the same time, low crop yields have led to a chronic shortage of food on the island. This paper, based on an analysis of archival materials and a detailed agronomic study of the farming system, analyzes the causes of this process of disintensification. Labor scarcity resulting from migrant wage employment and the growing importance of the fishing industry has been a major factor in the decline of agriculture on the island. The loss of soil conservation practices and serious weed infestations have contributed to the collapse of farm productivity. This study highlights the importance of understanding not only the local ecology but also the broader political and economic environment in order to explain farmers' decisions and the process of agricultural change.     

Did the Earth Move for You? The Social Seismology of a Natural Disaster in Maluku,Eastern Indonesia

In 1968, the volcano on the island of Nila in the Banda Sea erupted causing the inhabitants of this island to take temporary refuge on the nearby islands of Serua and Teun. Some ten years later, after a period of prolonged volcanic inactivity, the residents of Nila left their island again. This time, however, they were escorted by the Indonesian Navy and their departure from the island to a recently cleared site in southern Seram was of a more permanent nature. To a casual observer, the 1978 exodus looked, for all intents and purposes, like an invasion. Officially, it was called an evacuation (evakuasi). In time, it would take on the appearance of the government-initiated transmigration (trans-migrasi) program. In this paper, I explore the social seismology of this natural disaster and argue that displacement in this context amounts to more than just a shift in geographical space. It shakes the very foundations of identity, engendering, as it does, tectonic movements in social memory, cultural knowledge and environmental practice. Notwithstanding the destabilising effects of state-driven territorialisation, and its objectives of social order, political control and economic development, the people of Nila counteract this project of ‘humanitarian’ intervention through the enactment of their own political agendas, self-fashioning exercises and strategies of environmental reshaping.     

Invasion,establishment, and range expansion of two parasitic nematodes in the Canadian Arctic

Climate warming is occurring at an unprecedented rate in the Arctic and is having profound effects on host‐parasite interactions, including range expansion. Recently, two species of protostrongylid nematodes have emerged for the first time in muskoxen and caribou on Victoria Island in the western Canadian Arctic Archipelago. Umingmakstrongylus pallikuukensis, the muskox lungworm, was detected for the first time in 2008 in muskoxen at a community hunt on the southwest corner of the island and by 2012, it was found several hundred kilometers east in commercially harvested muskoxen near the town of Ikaluktutiak. In 2010, Varestrongylus sp., a recently discovered lungworm of caribou and muskoxen was found in muskoxen near Ikaluktutiak and has been found annually in this area since then. Whereas invasion of the island by U. pallikuukensis appears to have been mediated by stochastic movement of muskoxen from the mainland to the southwest corner of the island, Varestrongylus has likely been introduced at several times and locations by the seasonal migration of caribou between the island and the mainland. A newly permissive climate, now suitable for completion of the parasite life cycles in a single summer, likely facilitated the initial establishment and now drives range expansion for both parasites.     

Palynological assessment of Holocene mangrove vegetation at the American Memorial Park,Saipan, Northern Mariana Islands

Pollen and spores recovered from three cores of Holocene to recent deposits from the island of Saipan indicate the presence of mangrove vegetation, including Bruguiera and Acrostichum, on the island previous to World War II. The occurrence of Casuarina equisetifolia Linneaus 1759, from cores elsewhere on the island of Saipan, at depths predating the arrival of humans to the island, suggest that this tree species is endemic to Saipan rather than a recent invasive species. These findings will assist in replanting native vegetation once destroyed through wartime activities on the island.     

Borders,paradox and power

Border studies have grappled with, on the one hand, the need for the use of common themes or concepts while, on the other, the need for contextual specificity. Borders are sites that embody different potentialities: division and contact, conflict and cooperation, security and anxiety, creativity and oppression, among others. In short, they are sites of the paradoxical. Paradox, it is argued, is the common overarching conceptual characteristic of borders but which specific potentialities are embodied in a border and what prevails as a result of the ensuing power struggles requires contextual specificity. Cyprus, a divided island lying on various border lines, partly inside and partly outside the EU, presents a useful socio-political space in order to illustrate this argument by outlining the specific paradoxical aspects of its own border and the results of the ensuing power struggles.     

Precise region and the character of the pathogenicity island in clinical Vibrio parahaemolyticus strains

In this study, we determined the borders of the pathogenicity island in V. parahaemolyticus RIMD2210633 (Vp-PAI). Vp-PAI has features in common with Tn7 and other related elements at both terminal ends. Our findings indicate that the mobile element with a transposase which contains the DDE motif may have been involved in Vp-PAI formation.     

Effects of ecogeographic variables on genetic variation in montane mammals: implications for conservation in a global warming scenario

Aim Evolutionary theory predicts that levels of genetic variation in island populations will be positively correlated with island area and negatively correlated with island isolation. These patterns have been empirically established for oceanic islands, but little is known about the determinants of variation on habitat islands. The goals of this study were twofold. Our first aim was to test whether published patterns of genetic variation in mammals occurring on montane habitat islands in the American Southwest conformed to expectations based on evolutionary theory. The second aim of this research was to develop simple heuristic models to predict changes in genetic variation that may occur in these populations as a result of reductions in available mountaintop habitat in response to global warming. Location Habitat islands of conifer forest on mountaintops in the American Southwest. Methods Relationships between island area and isolation with measures of allozyme variation in four species of small mammal, namely the least chipmunk (Tamias minimus), Colorado chipmunk (Tamias quadrivittatus), red squirrel (Tamiasciurus hudsonicus), and Mexican woodrat (Neotoma mexicana), were determined using correlation and regression techniques. Significant relationships between island area and genetic variation were used to develop three distinct statistical models with which to predict changes in genetic variation following reduction in insular habitat area arising from global warming. Results Patterns of genetic variation in each species conformed to evolutionary predictions. In general, island area was the most important determinant of heterozygosity, while island isolation was the most important determinant of polymorphism and allelic diversity. The heuristic models predicted widespread reductions in genetic variation, the extent of which depended on the population and model considered. Main conclusions The results support a generalized pattern of genetic variation for any species with an insular distribution, with reduced variation in smaller, more isolated populations. We predict widespread reductions in genetic variation in isolated populations of montane small mammals in the American Southwest as a result of global warming. We conclude that climate‐induced reductions in the various dimensions of genetic variation may increase the probability of population extinction in both the short and long term.     

Moving Histories: An Analysis of the Dynamics of Place in North Ambrym,Vanuatu

Recent writing on the ethnogeography of Vanuatu has identified mobility and primordial connection as two counterpoised aspects of connection to place that have a long history in the archipelago. These themes are taken up in this paper in the specific case of north Ambrym, an island community in north‐central Vanuatu in which the accidental geography of active volcanoes has fostered an equally active interest in making connections outside the island. In the post‐contact period, Ambrymese were more mobile than many of their neighbours, as they recruited vigorously in a labour trade taking them to distant destinations and facilitating a fragmentation of the local population, already decimated by introduced disease. In addition, conversion of a large proportion of the population to Christianity brought local movement. The named domains, with their primordial connections to ancient sites replete with cosmo‐mythic significance, were reconstituted as villages of one denomination or another, containing members of many different origin sites. Cash‐cropping became characteristic of coastal, Christian settlements whose residents saw themselves as opposed to their ‘heathen’ neighbours. For the bush‐folk, kastom was both symbolic of their identification with the past and their justification for exclusive access to its popular manifestations in the artefact trade, in the present. In the pre‐Independence 1970s, local politics and pressure on productive resources including kastom, forced a radical re‐emphasis on primordial connection at the expense of the more ‘rhizomatic’ attachments inside and outside domains, the boundaries of districts and even the island itself that had been, until then, more characteristic of Ambrymese place‐making.     

The morphology, distribution and conservation implications of introduced rats, Rattus spp. in the granitic Seychelles

There are no native land mammals in the Seychelles archipelago other than bats. Introduced rats have reduced the conservation value of most islands. This paper compares the results of rat‐trapping carried out on eight islands in the granitic Seychelles, between July 1999 and April 2000. Trapping was carried out in both the dry and wet seasons. Three introduced rodent species were caught, including two species of rat (ship rat Rattus rattus Linnaeus and Norway rat R. norvegicus Berkenhout), but only one Rattus species occurred on each island. Both rat species were smaller than European or Asian conspecifics, and there were variations in the size and appearance of rats on different islands. Inter‐island differences in size and pelage colour are discussed.     

Larger body size on islands affects silvereye Zosterops lateralis song and call frequency

Differences in song repertoires and characteristics of island and mainland populations of the same avian species are usually explained by dispersal, cultural evolution and/or habitat differences. The influence of morphology is often overlooked, even though island populations are frequently morphologically distinct from mainland populations, and morphology could affect vocalizations. I compared morphological features, songs, contact calls and alarm calls of six isolated island populations of silvereye Zosterops lateralis with those of two mainland populations to examine whether differences between mainland and island vocalizations were consistent across vocalization types, and whether these differences could be linked to morphological differences. Vocalizations were lower in frequency on islands. Island individuals were larger (both in mass and body structure), and body mass was an important predictor of frequency in contact and alarm calls. I argue that this strong association results from the island rule (islands promote larger body sizes) and cascading effects of morphology on vocalization frequency in this species.     

Species delimitation and biogeography of the Ryukyu ground geckos,Goniurosaurus kuroiwae ssp. (Squamata: Eublepharidae), by use of mitochondrial and nuclear DNA analyses

In the Ryukyu Archipelago, Japan, Goniurosaurus geckos are currently divided into six allopatric taxa among nearby islands. Recent studies suggested the occurrence of large genetic divergence within a single island and the possible non‐monophyly of a few taxa, but their species delimitation is not well resolved. We investigated the taxonomic relationships between the possibly geographically overlapped, highly diverged entities as well as other island populations via dense sampling. Our mitochondrial and nuclear DNA analyses showed that the two genetic groups were distributed in parapatry within Okinawajima Island and that they were hybridizing in narrow area around the contact zone. Geohistorical evidence suggests that the restricted gene flow has been caused by some intrinsic isolation mechanisms. Thus, we conclude that the two lineages represent full species. Mitochondrial analysis also showed that the genetic differences among other island populations were comparable to those between these species, thereby suggesting the presence of seven full species, including one unnamed taxon. We also discuss the possible cause of this divergence and why it has occurred at such a fine geographic scale.     

Rapid,complete reproductive isolation in two closely related Zosterops White‐eye bird species despite broadly overlapping ranges*

Examining what happens when two closely related species come into secondary contact provides insight into the later stages of the speciation process. The Zosteropidae family of birds is one of the most rapidly speciating vertebrate lineages. Members of this family are highly vagile and geographically widespread, raising the question of how divergence can occur if populations can easily come into secondary contact. On the small island of Kolombangara, two closely related nonsister species of white‐eyes, Zosterops kulambangrae and Zosterops murphyi, are distributed along an elevational gradient and come into secondary contact at mid‐elevations. We captured 134 individuals of both species along two elevational transects. Using genotyping‐by‐sequencing data and a mitochondrial marker, we found no evidence of past hybridization events and strong persistence of species boundaries, even though the species have only been diverging for approximately 2 million years. We explore potential reproductive barriers that allow the two species to coexist in sympatry, including premating isolation based on divergence in plumage and song. We also conducted a literature review to determine the time it takes to evolve complete reproductive isolation in congeneric avian species/subspecies in secondary contact (restricted to cases where congeneric taxa are parapatric or have a hybrid zone), finding our study is one of the youngest examples of complete reproductive isolation studied in a genomic context reported in birds.     

Genetic variations within and between troops of the crab-eating macaque (Macaca fascicularis) on Sumatra,Java, Bali,Lombok and Sumbawa,Indonesia

Genetic variations within and between troops of the Indonesian crab-eating macaque (Macaca fascicularis) were studied. A total of 456 blood samples were collected from 29 free-ranging troops in 19 different localities on Sumatra, Java, Bali, Lombok and Sumbawa. Blood protein polymorphisms were examined electrophoretically. Mean genetic variability within troops was estimated to be P_poly=12.22% and =3.84%. Troops inhabiting small islands showed lower variability. Genetic differences were more marked between troops on different islands than between troops on the same island. Additionally, clinal variations of allelic frequencies at some loci were detected. The genetic features and socio-ecological and evolutionary implications are discussed.     

Small population instability and island settlement patterns

A model of extinction probability, based on the general theory of island biogeography [MacArthur and Wilson, 1967], is proposed for humans on oceanic islands; extinction probability is determined by island carrying capacity, frequency and amplitude of fluctuations in resources determining carrying capacity, and the net costs of contact and exchange between population units. The model predicts that extinction probability will determine island settlement patterns within an island group resulting in nonsettlement of islands with low carrying capacities and settlement of all islands with high carrying capacities. Data examined from the Marshall Islands tend to support the model. The model is extended to initial atoll colonization patterns. Possible requirements for initial settlement are suggested.Deceased.