The evolutionary history of the Mediterranean centipede Scolopendra cingulata (Latreille, 1829) (Chilopoda: Scolopendridae) across the Aegean archipelago

In this study we investigate the evolutionary relationships of Scolopendra cingulata (Latreille, 1829) within insular Greece. Our main goal is to infer the time frame of the differentiation of the species in the study area. In this regard, sequence data originating from three mitochondrial genes are used to reconstruct the evolutionary history of 47 insular populations of S.cingulata from the Aegean archipelago. Within the phylogenetic framework and by implementing a relaxed molecular clock methodology, we infer the time estimates of separations of the S.cingulata lineages. The results of the phylogenetic analysis support the presence of three distinct S.cingulata groups in the region. The first group accommodates populations from the eastern Aegean islands, and is closely related to the second group that hosts mainly populations of northern and central Cyclades. The third group is composed of insular populations originating from southern Cyclades. Different temporal splitting scenarios have been evaluated. Based on the scenario strongly supported by the data, we propose a biogeographical scenario that could account for the contemporary distribution of the species' lineages. The splitting events of S.cingulata are estimated to have occurred within the late Miocene. The historical events of the last 13.77Myr have shaped, through a series of mostly vicariant and dispersal incidents, the present-day biogeographical pattern of the species. © 2012 The Linnean Society of London

Network biogeography of a complex island system: the Aegean Archipelago revisited

Aim: The Aegean Archipelago has been the focal research area for identifying and testing several ecological and evolutionary patterns, yet its biogeographical subdivision has been somewhat overlooked, with the processes driving the assembly of the Aegean island plant communities still remaining largely unclear. To bridge this gap, we identify the biogeographical modules (highly linked subgroups of islands and plant taxa) within the Aegean Archipelago. Location: The Aegean Archipelago, Greece. Methods: We used a network approach to detect island biogeographical roles and modules, based on a large and detailed database including 1498 Aegean endemic and subendemic plant taxa distributed on 59 Aegean Islands and five adjacent mainland areas. Results: The Aegean was divided into six biogeographical modules; the network was significantly modular. None of the modules displayed all four possible biogeographical roles (connectors, module hubs, network hubs, peripherals). Six new biogeographical regions in the Aegean were identified. Main conclusions: The borders of the six biogeographical regions in the Aegean correspond well to the region's palaeogeographical evolution from the middle Miocene to the end of the Pleistocene. The Central Aegean acts as an ecogeographical filter for the distribution of several plant lineages across the Aegean Sea, while there seems to be a N–S-oriented biogeographical barrier in the Aegean corresponding to the palaeogeographical situation during the middle Ionian. These biogeographical barriers have been fundamental for both plants and animals. © 2016 John Wiley & Sons Lt

Past connections with the mainland structure patterns of insular species richness in a continental-shelf archipelago (Aegean Sea, Greece)

Recent research in island biogeography has highlighted the important role of late Quaternary sea-level fluctuations in shaping biogeographic patterns in insular systems but focused on oceanic systems. Through this study, we aim investigate how late Quaternary sea-level fluctuations shaped species richness patterns in continental-shelf island systems. Focusing on the Aegean archipelago, we first compiled maps of the area's geography using published data, under three sea-level stands: (a) current; (b) median sea-level over the last nine glacial–interglacial cycles (MSL); and (c) Last Glacial Maximum (LGM). We gathered taxon–island occurrences for multiple chorotypes of angiosperms, butterflies, centipedes, and reptiles. We investigated the impact of present-day and past geographic settings on chorological groups by analyzing island species–area relationships (ISARs) and using generalized linear mixed models (GLMMs) selection based on multiple metrics of goodness of fit. Our results confirm that the Aegean's geography has changed dramatically since the LGM, whereas the MSL only modestly differs from the present configuration. Apart for centipedes, paleogeographic changes affected both native and endemic species diversity through altering connections between land-bridge islands and the mainland. On land-bridge islands, we detected over-representation of native species and under-representation of endemics. Unlike oceanic islands, sea-level-driven increase of isolation and area contraction did not strongly shape patterns of species richness. Furthermore, the LGM configurations rather than the MSL configuration shaped patterns of endemic species richness. This suggests that even short episodes of increased connectivity with continental populations are sufficient to counteract the genetic differentiation of insular populations. On the other hand, the over-representation of native nonendemic species on land-bridge islands reflected MSL rather than LGM mainland connections. Our study shows that in terms of processes affecting species richness patterns, continental archipelagos differ fundamentally from oceanic systems because episodic connections with the mainland have profound effects on the biota of land-bridge islands. © 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd

Geographic changes in the Aegean Sea since the Last Glacial Maximum : Postulating biogeographic effects of sea-level rise on islands

In order to assess how the last sea level rise affected the Aegean archipelago, we quantified the magnitude andrate of geographic change for the Aegean islands during the last sea-level-rise episode (21 kyr BP–present)with a spatially explicit geophysical model. An island-specific Area-Distance-Change (ADC) typology was constructed,with higher ADC values representing a higher degree of change. The highest fragmentation rates ofthe Aegean archipelago occurred in tandem with the largest rates of sea-level-rise occurring between 17 kyrand 7 kyr ago. Sea-level rise resulted in an area loss for the Aegean archipelago of approximately 70%. Spatiotemporaldifferences in sea-level changes across the Aegean Sea and irregular bathymetry produced a variety of islandsurface-area loss responses, with area losses ranging from 20% to N90% per island. In addition, sea-levelrise led to increased island isolation, increasing distances of islands to continents to N200% for some islands.Wediscuss howrates of area contractions and distance increasesmay have affected biotas, their evolutionary historyand genetics. Five testable hypotheses are proposed to guide future research. We hypothesize that islandswith higher ADC-values will exhibit higher degrees of community hyper-saturation, more local extinctions, largergenetic bottlenecks, higher genetic diversity within species pools, more endemics and shared species on continentalfragments and higher z-values of the power-law species-area relationship. The developed typology andthe quantified geographic response to sea-level rise of continental islands, as in the Aegean Sea, present an idealresearch framework to test biogeographic and evolutionary hypotheses assessing the role of rates of area and distancechange affecting biota