Browsing by Author "Parmakelis, Aristeidis"
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- Comparative phylogeography of endemic Azorean arthropodsPublication . Parmakelis, Aristeidis; Rigal, François; Mourikis, Thanos; Balanika, Katerina; Terzopoulou, Sofia; Rego, Carla; Amorim, Isabel R.; Crespo, Luís C.; Pereira, Fernando E. A.; Triantis, Kostas A.; Whittaker, Robert J.; Borges, Paulo A. V.BACKGROUND: For a remote oceanic archipelago of up to 8 Myr age, the Azores have a comparatively low level of endemism. We present an analysis of phylogeographic patterns of endemic Azorean island arthropods aimed at testing patterns of diversification in relation to the ontogeny of the archipelago, in order to distinguish between alternative models of evolutionary dynamics on islands. We collected individuals of six species (representing Araneae, Hemiptera and Coleoptera) from 16 forest fragments from 7 islands. Using three mtDNA markers, we analysed the distribution of genetic diversity within and between islands, inferred the differentiation time-frames and investigated the inter-island migration routes and colonization patterns. RESULTS: Each species exhibited very low levels of mtDNA divergence, both within and between islands. The two oldest islands were not strongly involved in the diffusion of genetic diversity within the archipelago. The most haplotype-rich islands varied according to species but the younger, central islands contributed the most to haplotype diversity. Colonization events both in concordance with and in contradiction to an inter-island progression rule were inferred, while a non-intuitive pattern of colonization from western to eastern islands was also inferred. CONCLUSIONS: The geological development of the Azores has followed a less tidy progression compared to classic hotspot archipelagos, and this is reflected in our findings. The study species appear to have been differentiating within the Azores for <2 Myr, a fraction of the apparent life span of the archipelago, which may indicate that extinction events linked to active volcanism have played an important role. Assuming that after each extinction event, colonization was initiated from a nearby island hosting derived haplotypes, the apparent age of species diversification in the archipelago would be moved closer to the present after each extinction-recolonization cycle. Exploiting these ideas, we propose a general model for future testing.
- Development of 28 polymorphic microsatellite markers for the endemic Azorean spider Sancus acoreensis (Araneae, Tetragnathidae)Publication . Parmakelis, Aristeidis; Balanika, Katerina; Terzopoulou, Sofia; Rigal, François; Beasley, Rochelle R.; Jones, Kenneth L.; Lance, Stacey L.; Whittaker, Robert J.; Triantis, Kostas A.; Borges, Paulo A. V."We isolated and characterized a total of 28 microsatellite loci from Sancus acoreensis. Loci were screened in 26 individuals originating from seven (Flores, Faial, Pico, São Jorge, Terceira, São Miguel, and Santa Maria) out of the nine islands of the Azores. The number of alleles per locus ranged from 2 to 14, observed heterozygosity ranged from 0.040 to 0.708, and the probability of identity values ranged from 0.02 to 0.97. Sancus acoreensis is a Laurel forest specialist species, endemic to the Azores, and is facing a great extinction risk due to the severe fragmentation of its habitat. The newly developed microsatellite loci will aid in detecting signs of population bottlenecks and pinpoint the island populations that are facing the greatest risk of extinction. […]".
- Dispersal ability determines the scaling properties of species abundance distributions : a case study using arthropods from the AzoresPublication . Borda-de-Água, Luis; Whittaker, Robert J.; Cardoso, Pedro; Rigal, François; Santos, Ana M. C.; Amorim, Isabel R.; Parmakelis, Aristeidis; Triantis, Kostas A.; Pereira, Henrique M.; Borges, Paulo A. V.Species abundance distributions (SAD) are central to the description of diversity and have played a major role in the development of theories of biodiversity and biogeography. However, most work on species abundance distributions has focused on one single spatial scale. Here we used data on arthropods to test predictions obtained with computer simulations on whether dispersal ability influences the rate of change of SADs as a function of sample size. To characterize the change of the shape of the SADs we use the moments of the distributions: the skewness and the raw moments. In agreement with computer simulations, low dispersal ability species generate a hump for intermediate abundance classes earlier than the distributions of high dispersal ability species. Importantly, when plotted as function of sample size, the raw moments of the SADs of arthropods have a power law pattern similar to that observed for the SAD of tropical tree species, thus we conjecture that this might be a general pattern in ecology. The existence of this pattern allows us to extrapolate the moments and thus reconstruct the SAD for larger sample sizes using a procedure borrowed from the field of image analysis based on scaled discrete Tchebichef moments and polynomials.
- New records and detailed distribution and abundance of selected arthropod species collected between 1999 and 2011 in Azorean native forestsPublication . Borges, Paulo A. V.; Gaspar, Clara; Crespo, Luís C.; Rigal, François; Cardoso, Pedro; Pereira, Fernando; Rego, Carla; Amorim, Isabel; Melo, Catarina; Aguiar, Carlos; André, Genage; Pereira, Enésima; Ribeiro, Sérvio P.; Hortal, Joaquín; Santos, Ana M. C.; Barcelos, Luís Miguel Duarte; Enghoff, H.; Mahnert, Volker; Pita, Margarida T.; Ribes, Jordi; Baz, Arturo; Sousa, António B.; Vieira, Virgilio; Wunderlich, Jörg; Parmakelis, Aristeidis; Whittaker, Robert J.; Quartau, José A.; Serrano, Artur R. M.; Triantis, Kostas A.BACKGROUND: In this contribution we present detailed distribution and abundance data for arthropod species identified during the BALA – Biodiversity of Arthropods from the Laurisilva of the Azores (1999-2004) and BALA2 projects (2010-2011) from 18 native forest fragments in seven of the nine Azorean islands (all excluding Graciosa and Corvo islands, which have no native forest left). NEW INFORMATION: Of the total 286 species identified, 81% were captured between 1999 and 2000, a period during which only 39% of all the samples were collected. On average, arthropod richness for each island increased by 10% during the time frame of these projects. The classes Arachnida, Chilopoda and Diplopoda represent the most remarkable cases of new island records, with more than 30% of the records being novelties. This study stresses the need to expand the approaches applied in these projects to other habitats in the Azores, and more importantly to other less surveyed taxonomic groups (e.g. Diptera and Hymenoptera). These steps are fundamental for getting a more accurate assessment of biodiversity in the archipelago.