Occasional Migration Research Articles

Survey of the fish fauna of the water bodies of the city of Kharkiv

The study of the biodiversity of urbanized landscapes, in the context of their permanent expansion, is becoming increasingly important as part of environmental management. The proposed review considers the history of the study and the results of modern research on the ichthyofauna of water bodies in and around the city of Kharkiv. The study includes data obtained during archeological excavations. The existing water fund is estimated as a habitat for fish in the city. We compiled a modern systematic list of the fish fauna, determined its place in the general zoogeographical zonation of the Palearctic, and analyzed the ecological and faunistic characteristics of the fish assemblages, which created a basis for a general assessment of the current state and prospects for changes in the fish community within the city. The state of recreational fishing in the waters of Kharkiv as the main type of utilization of fish resources on its territory is analyzed. The current fish fauna of the water bodies of Kharkiv and its environs consists of 32 species belonging to 31 genera, 11 families, 7 orders, and 4 superorders of bony fish, as well as one hybrid form of silver and bighead carps, whose abundance is maintained only by artificial introduction into water bodies outside Kharkiv with subsequent occasional migration to the city, and two diploid-polyploid hybridogenic complexes of fish of the genera Carassius and Cobitis, whose reproductive characteristics require further study. Five species have disappeared from the local fish fauna, i.e. four species of bony fish (common crucian carp Carassius carassius, Black Sea roach Rutilus frisii, asp Leuciscus aspius, Danilevsky's dace Leuciscus danilewskii) and the Ukrainian lamprey Eudontomyzon mariae, which used to live in the city or water bodies and watercourses of the adjacent territories. Thirteen fish species (41% of the total species composition) have a conservation status and require special measures for their protection according to national and international regulations. The share of non-native species in the ichthyofauna of Kharkiv is quite significant – eight species (22% of the total number of registered species and forms). The fish fauna of the city is dominated by freshwater fishes, limnophilic or indifferent to the current speed, with phytophilic or psammolithophilic portion spring and summer spawning, not belonging to any particular habitat.

A retrospective and regional approach assessing the genomic diversity of Salmonella Dublin.

From a historically rare serotype, Salmonella enterica subsp. enterica Dublin slowly became one of the most prevalent Salmonella in cattle and raw milk cheese in some regions of France. We present a retrospective genomic analysis of 480 S. Dublin isolates to address the context, evolutionary dynamics, local diversity and the genesis processes of regional S. Dublin outbreaks events between 2015 and 2017. Samples were clustered and assessed for correlation against metadata including isolation date, isolation matrices, geographical origin and epidemiological hypotheses. Significant findings can be drawn from this work. We found that the geographical distance was a major factor explaining genetic groups in the early stages of the cheese production processes (animals, farms) while down-the-line transformation steps were more likely to host genomic diversity. This supports the hypothesis of a generalised local persistence of strains from animal to finished products, with occasional migration. We also observed that the bacterial surveillance is representative of diversity, while targeted investigations without genomics evidence often included unrelated isolates. Combining both approaches in phylogeography methods allows a better representation of the dynamics, of outbreaks.

Spatially explicit paleogenomic simulations support cohabitation with limited admixture between Bronze Age Central European populations

The Bronze Age is a complex period of social, cultural and economic changes. Recent paleogenomic studies have documented a large and rapid genetic change in early Bronze Age populations from Central Europe. However, the detailed demographic and genetic processes involved in this change are still debated. Here we have used spatially explicit simulations of genomic components to better characterize the demographic and migratory conditions that may have led to this change. We investigated various scenarios representing the expansion of pastoralists from the Pontic steppe, potentially linked to the Yamnaya cultural complex, and their interactions with local populations in Central Europe, considering various eco-evolutionary factors, such as population admixture, competition and long-distance dispersal. Our results do not support direct competition but rather the cohabitation of pastoralists and farmers in Central Europe, with limited gene flow between populations. They also suggest occasional long-distance migrations accompanying the expansion of pastoralists and a demographic decline in both populations following their initial contact. These results link recent archaeological and paleogenomic observations and move further the debate of genomic changes during the early Bronze Age.

Long-term spatiotemporal genetic structure of an accidental parasitoid introduction, and local changes in prevalence of its associated Wolbachia symbiont.

Population bottlenecks associated with founder events strongly impact the establishment and genetic makeup of populations. In addition to their genotype, founding individuals also bring along parasites, as well as symbionts that can manipulate the phenotype of their host, affecting the host population establishment, dynamics and evolution. Thus, to understand introduction, invasion, and spread, we should identify the roles played by accompanying symbionts. In 1991, the parasitoid wasp, Hyposoter horticola, and its associated hyperparasitoid were accidentally introduced from the main Åland islands, Finland, to an isolated island in the archipelago, along with their host, the Glanville fritillary butterfly. Though the receiving island was unoccupied, the butterfly was present on some of the small islands in the vicinity. The three introduced species have persisted locally ever since. A strain of the endosymbiotic bacterium Wolbachia has an intermediate prevalence in the parasitoid H. horticola across the main Åland population. The infection increases its susceptibility of to hyperparasitism. We investigated the establishment and spread of the parasitoid, along with patterns of prevalence of its symbiont using 323specimens collected between 1992 and 2013, from five localities across Åland, including the source and introduced populations. Using 14microsatellites and one mitochondrial marker, we suggest that the relatively diverse founding population and occasional migration between islands might have facilitated the persistence of all isolated populations, despite multiple local population crashes. We also show that where the hyperparasitoid is absent, and thus selection against infected wasp genotypes is relaxed, there is near-fixation of Wolbachia.

Far eastern curlew and whimbrel prefer flying low - wind support and good visibility appear only secondary factors in determining migratory flight altitude

BackgroundIn-flight conditions are hypothesized to influence the timing and success of long-distance migration. Wind assistance and thermal uplift are thought to reduce the energetic costs of flight, humidity, air pressure and temperature may affect the migrants’ water balance, and clouds may impede navigation. Recent advances in animal-borne long-distance tracking enable evaluating the importance of these factors in determining animals’ flight altitude.MethodsHere we determine the effects of wind, humidity, temperature, cloud cover, and altitude (as proxy for climbing costs and air pressure) on flight altitude selection of two long-distance migratory shorebirds, far eastern curlew (Numenius madagascariensis) and whimbrel (Numenius phaeopus). To reveal the predominant drivers of flight altitude selection during migration we compared the atmospheric conditions at the altitude the birds were found flying with conditions elsewhere in the air column using conditional logistic mixed effect models.ResultsOur results demonstrate that despite occasional high-altitude migrations (up to 5550 m above ground level), our study species typically forego flying at high altitudes, limiting climbing costs and potentially alleviating water loss and facilitating navigation. While mainly preferring migrating at low altitude, notably in combination with low air temperature, the birds also preferred flying with wind support to likely reduce flight costs. They avoided clouds, perhaps to help navigation or to reduce the risks from adverse weather.ConclusionsWe conclude that the primary determinant of avian migrant’s flight altitude selection is a preference for low altitude, with wind support as an important secondary factor. Our approach and findings can assist in predicting climate change effects on migration and in mitigating bird strikes with air traffic, wind farms, power lines, and other human-made structures.

Phylogeography and population structure of the tsetse fly Glossina pallidipes in Kenya and the Serengeti ecosystem.

Glossina pallidipes is the main vector of animal African trypanosomiasis and a potential vector of human African trypanosomiasis in eastern Africa where it poses a large economic burden and public health threat. Vector control efforts have succeeded in reducing infection rates, but recent resurgence in tsetse fly population density raises concerns that vector control programs require improved strategic planning over larger geographic and temporal scales. Detailed knowledge of population structure and dispersal patterns can provide the required information to improve planning. To this end, we investigated the phylogeography and population structure of G. pallidipes over a large spatial scale in Kenya and northern Tanzania using 11 microsatellite loci genotyped in 600 individuals. Our results indicate distinct genetic clusters east and west of the Great Rift Valley, and less distinct clustering of the northwest separate from the southwest (Serengeti ecosystem). Estimates of genetic differentiation and first-generation migration indicated high genetic connectivity within genetic clusters even across large geographic distances of more than 300 km in the east, but only occasional migration among clusters. Patterns of connectivity suggest isolation by distance across genetic breaks but not within genetic clusters, and imply a major role for river basins in facilitating gene flow in G. pallidipes. Effective population size (Ne) estimates and results from Approximate Bayesian Computation further support that there has been recent G. pallidipes population size fluctuations in the Serengeti ecosystem and the northwest during the last century, but also suggest that the full extent of differences in genetic diversity and population dynamics between the east and the west was established over evolutionary time periods (tentatively on the order of millions of years). Findings provide further support that the Serengeti ecosystem and northwestern Kenya represent independent tsetse populations. Additionally, we present evidence that three previously recognized populations (the Mbeere-Meru, Central Kenya and Coastal “fly belts”) act as a single population and should be considered as a single unit in vector control.

Survival and recruitment in the population ecology of the endangered Bombina pachypus (Amphibia: Anura)

Abstract Global amphibian decline is a subject of great conservation concern, yet often basic demographic information is absent, which prevents the understanding of population trends and the planning of effective conservation management. We analysed capture-mark-recapture data from six populations of the endangered Bombina pachypus in order to understand the relative contribution of survival and recruitment to population growth, and to assess if any differences exist among populations in terms of their population dynamics. We found that survival was rather high and generally constant among sites, and recruitment was low, with the exception of two single years at one site. Population growth depended on survival on all sites, except the years following high recruitment at one site. Annual population size was generally lower than 30 individuals, but in one site it was estimated to be larger than 50. Our findings suggest that juvenile survival is more important for population dynamics than recruitment from the larval to the juvenile stage. We also suggest that the low recruitment rates we recorded was a result of juvenile dispersal, and that when populations exhibited high recruitment it was due to occasional successful migration or local recruitment. This pattern could represent a way to counterbalance the risk of inbreeding in populations composed of few individuals, a common characteristic of populations of B. pachypus. Finally, we suggest that conservation measures for B. pachypus should be planned at the landscape scale, and should not be limited solely to the breeding site and its close surroundings.

Habitat Predicts Levels of Genetic Admixture in Saccharomyces cerevisiae.

Genetic admixture can provide material for populations to adapt to local environments, and this process has played a crucial role in the domestication of plants and animals. The model yeast, Saccharomyces cerevisiae, has been domesticated multiple times for the production of wine, sake, beer, and bread, but the high rate of admixture between yeast lineages has so far been treated as a complication for population genomic analysis. Here, we make use of the low recombination rate at centromeres to investigate admixture in yeast using a classic Bayesian approach and a locus-by-locus phylogenetic approach. Using both approaches, we find that S. cerevisiae from stable oak woodland habitats are less likely to show recent genetic admixture compared with those isolated from transient habitats such as fruits, wine, or human infections. When woodland yeast strains do show recent genetic admixture, the degree of admixture is lower than in strains from other habitats. Furthermore, S. cerevisiae populations from oak woodlands are genetically isolated from each other, with only occasional migration between woodlands and local fruit habitats. Application of the phylogenetic approach suggests that there is a previously undetected population in North Africa that is the closest outgroup to the European S. cerevisiae, including the domesticated Wine population. Careful testing for admixture in S. cerevisiae leads to a better understanding of the underlying population structure of the species and will be important for understanding the selective processes underlying domestication in this economically important species.

A tipping point in parapatric speciation

More than two loci are involved in reproductive isolation in most cases of putative recent speciation. We study the speciation between two geographically isolated populations connected by infrequent migration, in which incompatibility is controlled by quantitative loci. Incompatibility genetic distance is defined as the fraction of compatibility controlling loci that are different between individuals. Speciation is established when genetic distance reaches a threshold level in spite of occasional migration and subsequent hybridization that reduce genetic distance. With stochastic analysis, we investigate how the time to speciation depends on the manner in which the magnitude of incompatibility increases with genetic distance. Results are: (1) The time to speciation is short if the migration rate is smaller than the mutation rate, or if intermediate levels of genetic distance cause mild incompatibility, making migrants less effective in reducing genetic distance. (2) Genetic distance may fluctuate around a positive quasi-equilibrium level for a long time, and suddenly show a quick passage to speciation when it goes beyond a “tipping point.” Notably a gradual increase in incompatibility can result in a sudden and rapid formation of a new species. (3) Speciation becomes very slow if incompatibility is effective for individuals differing at only one locus. These findings provide testable predictions on reproductive traits controlled by specific incompatibility accumulation forms that facilitate the speciation process.

Planktonic foraminiferal zonation and sea-level changes in the upper Maastrichtian-middle Danian successions of Meghalaya, India

The biostratigraphic study of the upper Maastrichtian- middle Danian shelf successions of Therriaghat and Mahadeo in Meghalaya, India allowed for the identification of sixty seven species of planktonic foraminifera and recognized the following four zones and eleven subzones: in upperMaastrichtian, Racemiguembelina fructicosa, Pseudoguembelina hariaensis, Pseudoguembelina palpebra and Plummerita hantkeninoides Subzones within the Abathomphalus mayaroensis Zone; in lower-middle Danian Hedbergella holmdelensis and Parvularugoglobigerina longiapertura Subzones within the Guembelitria cretacea Zone, Eoglobigerina fringa and Eoglobigerina praeedita Subzones within the Parvularugoglobigerina eugubina Zone and Parasubbotina pseudobulloides Subzone, Subbotina triloculinoides and Globanomalina compressa Subzones within the uppermost Eoglobigerina edita Zone. The sections are biostratigraphically continuous across the Cretaceous-Paleogene boundary, but the tectonic development of the unstable Therriaghat and Mahadeo blocks caused local tectono-eustatic differences between the two blocks in litho- and biostratigraphy, foraminiferal dispersal, sea-level changes and depositional environments. The succession of the Therriaghat block,where 4 zones and 11 subzoneswere identified, is more complete than the succession of theMahadeo block, which comprises 3 zones and 6 subzones. The ratio of planktonic to benthic foraminifera allowed for the recognition of five transgressive-regressive cycles, most of which have subcycles and pulses. These cycles were calibrated using the planktonic foraminiferal zonation, allowing for detailed documentation of the local history of sea-level change. The extra-basinal tectono-thermal influence, frequent local sea-level changes, suspended clay and microspherules, and greenhouse effect of volcanism caused an increase of temperature and biotic stress in the shelf waters and consequently turnover in the planktonic foraminiferal assemblages, occasional migration and re-appearance, widespread predation, morphological aberrations, dwarfed and anomalous tests, abraded forms andmorphogroups. These paleoenvironmental changesmay have modified the local range of taxa, and the extension of biozones, so that some of the recognized subzones can be local, such as Eoglobigerina fringa and Eoglobigerina praeedita Subzones. Nonetheless, the planktonic foraminiferal assemblages that maintained usual trend of evolution are useful to unravel the complexities of local eustatic history.

Climate change and variability impacts on agricultural production and livelihood systems in Western Tanzania

This article presents findings from a study conducted in Kasulu District in western Tanzania, to assess the impacts, vulnerability and adaptive capacity to climate change and variability of natural and social systems in various agro-ecological zones of Tanzania. Focus-group discussion, households and key informants interviews were used in data collection, also including physical observations and reviews of literature. Findings indicated that there is high dependence on agricultural production, and hence on natural resources, which makes the livelihoods of these communities potentially vulnerable to negative impacts of climate change associated with decreased agricultural productivity, food insecurity and constrained water availability. Uneven seasonal distribution of rainfall and increased temperature are major concerns for the area. Meteorological records confirm that there has been steady increase in mean maximum temperature, which affects the natural systems, influencing the phenological processes in vegetation and increasing evapo-transpiration rates, and increasing risks of crop pests and disease outbreaks. Among the local adaptation options have been the shift to more drought-tolerant and disease-resistant crop varieties and occasional migration to areas with better agricultural potential. While most societies are fundamentally adaptive and have adapted to similar climatic risks, the existing adaptation mechanisms seem to be inadequate. To facilitate local adaptations, there is a need for more information to quantify the magnitude of climate-change impacts and separate them from non-climatic factors with compounding effects. The latter is particularly important for addressing key livelihood components that seem to be most affected by climate change.

Transmission of Foot-and-Mouth Disease SAT2 Viruses at the Wildlife-Livestock Interface of Two Major Transfrontier Conservation Areas in Southern Africa.

Over a decade ago, foot-and-mouth disease (FMD) re-emerged in Southern Africa specifically in beef exporting countries that had successfully maintained disease-free areas in the past. FMD virus (FMDV) serotype SAT2 has been responsible for a majority of these outbreaks. Epidemiological studies have revealed the importance of the African buffalo as the major wildlife FMD reservoir in the region. We used phylogeographic analysis to study dynamics of FMD transmission between buffalo and domestic cattle at the interface of the major wildlife protected areas in the region currently encompassing two largest Transfrontier conservation areas: Kavango–Zambezi (KAZA) and Great Limpopo (GL). Results of this study showed restricted local occurrence of each FMDV SAT2 topotypes I, II, and III, with occasional virus migration from KAZA to GL. Origins of outbreaks in livestock are frequently attributed to wild buffalo, but our results suggest that transmission from cattle to buffalo also occurs. We used coalescent Bayesian skyline analysis to study the genetic variation of the virus in cattle and buffalo, and discussed the association of these genetic changes in the virus and relevant epidemiological events that occurred in this area. Our results show that the genetic diversity of FMDV SAT2 has decreased in buffalo and cattle population during the last decade. This study contributes to understand the major dynamics of transmission and genetic variation of FMDV SAT2 in Southern Africa, which will could ultimately help in designing efficient strategies for the control of FMD at a local and regional level.

Transnacionalismo, juventude rural e a busca de reconhecimento

Resumo Este texto trata de uma parcela da juventude brasileira contemporânea que tem vivenciado singularidades no processo de transição para a vida adulta ocasionadas pelas migrações internacionais. São jovens moradores de um município rural marcado pelo transnacionalismo. Nosso objetivo é problematizar a condição juvenil nesse contexto, buscando evidenciar os elementos empíricos do transnacionalismo e sua influência na vida dos jovens, na transição para a vida adulta e na busca de reconhecimento. Os dados utilizados na análise são resultados de um estudo com jovens de famílias transnacionais, aqui identificados como filhos da migração. O estudo foi desenvolvido entre 2009 e 2013 por meio de uma etnografia, utilizando como principais formas de coleta de dados a observação direta e participante. A pesquisa de campo foi desenvolvida durante oito meses, em um município rural da região mineira de Governador Valadares, quando também foram aplicados questionários e entrevistas individuais e coletivas. Os resultados apresentados neste artigo evidenciam: as principais características do transnacionalismo nesse local de origem das migrações internacionais; aspectos da condição juvenil, das famílias transnacionais, da transição para a vida adulta e a busca dos jovens por ser alguém na vida, compreendida como expressão da busca por reconhecimento.

Variation at the DRD4 locus is associated with wariness and local site selection in urban black swans.

BackgroundInteractions between wildlife and humans are increasing. Urban animals are often less wary of humans than their non-urban counterparts, which could be explained by habituation, adaptation or local site selection. Under local site selection, individuals that are less tolerant of humans are less likely to settle in urban areas. However, there is little evidence for such temperament-based site selection, and even less is known about its underlying genetic basis. We tested whether site selection in urban and non-urban habitats by black swans (Cygnus atratus) was associated with polymorphisms in two genes linked to fear in animals, the dopamine receptor D4 (DRD4) and serotonin transporter (SERT) genes.ResultsWariness in swans was highly repeatable between disturbance events (repeatability = 0.61) and non-urban swans initiated escape from humans earlier than urban swans. We found no inter-individual variation in the SERT gene, but identified five DRD4 genotypes and an association between DRD4 genotype and wariness. Individuals possessing the most common DRD4 genotype were less wary than individuals possessing rarer genotypes. As predicted by the local site selection hypothesis, genotypes associated with wary behaviour were over three times more frequent at the non-urban site. This resulted in moderate population differentiation at DRD4 (FST = 0.080), despite the sites being separated by only 30 km, a short distance for this highly-mobile species. Low population differentiation at neutrally-selected microsatellite loci and the likely occasional migration of swans between the populations reduces the likelihood of local site adaptations.ConclusionOur results suggest that wariness in swans is partly genetically-determined and that wary swans settle in less-disturbed areas. More generally, our findings suggest that site-specific management strategies may be necessary that consider the temperament of local animals.

Complex spatial clonal structure in the macroalgae Fucus radicans with both sexual and asexual recruitment.

In dioecious species with both sexual and asexual reproduction, the spatial distribution of individual clones affects the potential for sexual reproduction and local adaptation. The seaweed Fucus radicans, endemic to the Baltic Sea, has separate sexes, but new attached thalli may also form asexually. We mapped the spatial distribution of clones (multilocus genotypes, MLGs) over macrogeographic (>500km) and microgeographic (<100m) scales in the Baltic Sea to assess the relationship between clonal spatial structure, sexual recruitment, and the potential for natural selection. Sexual recruitment was predominant in some areas, while in others asexual recruitment dominated. Where clones of both sexes were locally intermingled, sexual recruitment was nevertheless low. In some highly clonal populations, the sex ratio was strongly skewed due to dominance of one or a few clones of the same sex. The two largest clones (one female and one male) were distributed over 100-550km of coast and accompanied by small and local MLGs formed by somatic mutations and differing by 1-2 mutations from the large clones. Rare sexual events, occasional long-distance migration, and somatic mutations contribute new genotypic variation potentially available to natural selection. However, dominance of a few very large (and presumably old) clones over extensive spatial and temporal scales suggested that either these have superior traits or natural selection has only been marginally involved in the structuring of genotypes.

Phylogeography of a widespread species: pre-glacial vicariance, refugia, occasional blocking straits and long-distance migrations.

Phylogeographic studies give us the opportunity to reconstruct the historical migrations of species and link them with climatic and geographic variation. They are, therefore, a key tool to understanding the relationships among biology, geology and history. One of the most interesting biogeographical areas of the world is the Mediterranean region. However, in this area, the description of concordant phylogeographic patterns is quite scarce, which limits the understanding of evolutionary patterns related to climate. Species with one-dimensional distribution ranges, such as the strawberry tree (Arbutus unedo), are particularly useful to unravel these patterns. Here, we describe its phylogeographic structure and check for concordance with patterns seen in other Mediterranean plants: longitudinal/latitudinal clines of diversity, evidence for glacial refugia and the role of sea straits in dispersal. We also identify the most likely source for the disjunct Irish population. With this aim, we sequenced four chloroplast non-coding fragments of A. unedo from 23 populations covering its whole distribution. We determined the genetic diversity, population structure, haplotype genealogy and time to the most recent common ancestor. The genealogy revealed two clades that separated during the last 700 ky but before the last glacial maximum. One clade occupies Atlantic Iberia and North Africa, while the other occurs in the Western Mediterranean. The Eastern Mediterranean is inhabited by newer haplotypes derived from both clades, while the Irish population is closely related to Iberian demes. The straits of Sicily and Gibraltar partially restricted the gene flow. We concluded that a vicariance event during the Late Quaternary in the western end of the species' range followed by eastward migration seems a likely explanation for the observed phylogeographic pattern. The role of straits indicates an occasional communication between Europe and North Africa, suggesting that the latter was a novel refugia. The East-West genetic split in Iberia is consistent with the refugia-within-refugia model. Finally, the strawberry tree possibly reached Ireland from Iberia instead of throughout the maritime fringe of France as previously thought.

Population structure of the Chagas disease vector Triatoma infestans in an urban environment.

Chagas disease is a vector-borne disease endemic in Latin America. Triatoma infestans, a common vector of this disease, has recently expanded its range into rapidly developing cities of Latin America. We aim to identify the environmental features that affect the colonization and dispersal of T. infestans in an urban environment. We amplified 13 commonly used microsatellites from 180 T. infestans samples collected from a sampled transect in the city of Arequipa, Peru, in 2007 and 2011. We assessed the clustering of subpopulations and the effect of distance, sampling year, and city block location on genetic distance among pairs of insects. Despite evidence of genetic similarity, the majority of city blocks are characterized by one dominant insect genotype, suggesting the existence of barriers to dispersal. Our analyses show that streets represent an important barrier to the colonization and dispersion of T. infestans in Arequipa. The genetic data describe a T. infestans infestation history characterized by persistent local dispersal and occasional long-distance migration events that partially parallels the history of urban development.

Pb Isotopic Compositions of Fin Whale Baleen Plates – A Clue to Unravel Individual Migrations between the Atlantic Ocean and the Mediterranean Sea?

To assess Mediterranean fin whale ecology and impacts of environmental changes, Pb content and isotopic composition were measured on baleen plates of fin whales stranded on Mediterranean and Bay of Biscay coasts. Pb contents of fin whale baleen plate reflect that of their diet and thus of the dissolved Pb content of the upper 200 meters of the surface ocean. Using Pb isotopes, baleen plates allow reconstituting the evolution of anthropogenic Pb pollution and showing that stranded Mediterranean fin whales constitute a specific population that is resident of the Mediterranean Sea with occasional migrations to the Atlantic Ocean.

Wingless and intermorphic males in the ant Cardiocondyla venustula

The ant genus Cardiocondyla is characterized by a pronounced male diphenism with wingless fighter males and winged disperser males. Winged males have been lost convergently in at least two species-rich clades. Here, we describe the morphological variability of males of Cardiocondyla venustula from uThukela valley, South Africa. Winged males appear to be absent from this species. However, in addition to wingless (“ergatoid”) males with widely fused thoracic sutures and without ocelli, “intermorphic” males exist that combine the typical morphology of wingless males with characteristics of winged males, e.g., more pronounced thoracic sutures, rudimentary ocelli, and vestigial wings. Similar “intermorphic” males have previously been described from one of several genetically distinct lineages of the Southeast Asian “Cardiocondyla kagutsuchi” complex (Insect. Soc. 52: 274-281, 2005). To determine whether male morphology is associated with distinct clades also in C. venustula, we sequenced a 631 bp fragment of mitochondrial DNA of workers from 13 colonies. We found six haplotypes with a sequence variation of up to 5.7 %. Intermorphic and wingless males did not appear to be associated with a particular of these lineages and within colonies showed the same sequence. Interestingly, two colonies contained workers with different haplotypes, suggesting the occasional migration of queens and/or workers between colonies.

A Modification to the Fascia-Bone-Fascia Technique for Repair of the Middle Fossa Floor

A commonly used method for resurfacing of the middle fossa floor is the fascia-bone-fascia technique. One disadvantage of this technique however is the occasional migration of the bone graft. To prevent this, we have modified the technique to include securing of the graft using simple craniotomy fixation materials. We have now used this method in five patients, all of whom have had satisfactory clinical outcomes. Follow-up imaging has demonstrated the grafts to have remained in their original position.