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Red Sea (red + sea)
Terms modified by Red Sea Selected AbstractsUnusual synchronization of Red Sea fish energy expendituresECOLOGY LETTERS, Issue 2 2003Lewi Stone Abstract The highly gregarious goat fish Parupeneus forskalii found in the Red Sea at Eilat, Israel exhibit highly synchronous swimming and feeding activity. Five fish were studied under controlled conditions and highly resolved time-series of their energy expenditures were measured. All fish demonstrated strong phase synchronization in that their activity levels, although erratic in time and intensity, were collectively coordinated and peaked simultaneously together. The synchronization of these wildly varying, and possibly chaotic signals of energy expenditures, were quantified using phase analysis. We suggest that, ecologically, this collective synchronization is a strategy that increases food-catch. [source] Thickness of the lithosphere east of the Dead Sea TransformGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2006Ayman Mohsen SUMMARY We use the S receiver function method to study the lithosphere at the Dead Sea Transform (DST). A temporary network of 22 seismic broad-band stations was operated on both sides of the DST from 2000 to 2001 as part of the DESERT project. We also used data from six additional permanent broad-band seismic stations at the DST and in the surrounding area, that is, in Turkey, Saudi Arabia, Egypt and Cyprus. Clear S -to- P converted phases from the crust,mantle boundary (Moho) and a deeper discontinuity, which we interpret as lithosphere,asthenosphere boundary (LAB) have been observed. The Moho depth (30,38 km) obtained from S receiver functions agrees well with the results from P receiver functions and other geophysical data. We observe thinning of the lithosphere on the eastern side of the DST from 80 km in the north of the Dead Sea to about 65 km at the Gulf of Aqaba. On the western side of the DST, the few data indicate a thin LAB of about 65 km. For comparison, we found a 90-km-thick lithosphere in eastern Turkey and a 160-km-thick lithosphere under the Arabian shield, respectively. These observations support previous suggestions, based on xenolith data, heat flow observations, regional uplift history and geodynamic modelling, that the lithosphere around DST has been significantly thinned in the Late Cenozoic, likely following rifting and spreading of the Red Sea. [source] Temporal dynamics and nestedness of an oceanic island bird faunaGLOBAL ECOLOGY, Issue 4 2006Ermias T. Azeria ABSTRACT Aim, To examine temporal variation in nestedness and whether nestedness patterns predict colonization, extinction and turnover across islands and species. Location, Dahlak Archipelago, Red Sea. Method, The distributions of land birds on 17 islands were recorded in two periods 30 years apart. Species and islands were reordered in the Nestedness Temperature Calculator, software for assessing degrees of nestedness in communities. The occupancy probability of each cell, i.e. species,island combinations, was calculated in the nested matrix and an extinction curve (boundary line) was specified. We tested whether historical and current nested ranks of species and islands were correlated, whether there was a relationship between occupancy probability (based on the historical data) and number of extinctions or colonizations (regression analyses) and whether the boundary line could predict extinctions and colonizations (chi-square analyses). Results, Historical and current nested ranks of islands and species were correlated but changes in occupancy patterns were common, particularly among bird species with intermediate incidence. Extinction and turnover of species were higher for small than large islands, and colonization was negatively related to isolation. As expected, colonizations were more frequent above than below the boundary line. Probability of extinction was highest at intermediate occupancy probability, giving a quadratic relationship between extinction and occupancy probability. Species turnover was related to the historical nested ranks of islands. Colonization was related negatively while extinction and occupancy turnover were related quadratically to historical nested ranks of species. Main conclusions, Some patterns of the temporal dynamics agreed with expectations from nested patterns. However, the accuracy of the predictions may be confounded by regional dynamics and distributions of idiosyncratic, resource-limited species. It is therefore necessary to combine nestedness analysis with adequate knowledge of the causal factors and ecology of targeted species to gain insight into the temporal dynamics of assemblages and for nestedness analyses to be helpful in conservation planning. [source] Evidence for Pharaonic Seagoing Ships at Mersa/Wadi Gawasis, EgyptINTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 1 2010Cheryl Ward Cedar ship-timbers and associated debris from Mersa/Wadi Gawasis on the Red Sea provide direct evidence for seafaring in complex watercraft built with standard Egyptian shipbuilding technologies. The Middle Kingdom craft buried at Dashur and disassembled timbers from Lisht (c.1850 and 1950 BC) provide the best parallels for most of the Gawasis finds, but two steering-oar blades are more comparable to early New Kingdom examples. A new type of hull-construction technology is presented, along with descriptions of maritime artefacts and site activities. © 2010 The Authors [source] Abundance and clonal replication in the tropical corallimorpharian Rhodactis rhodostomaINVERTEBRATE BIOLOGY, Issue 4 2000Nanette E. Chadwick-Furman Abstract. The corallimorpharian Rhodactis rhodostoma appears to be an opportunistic species capable of rapidly monopolizing patches of unoccupied shallow substrate on tropical reefs. On a fringing coral reef at Eilat, Israel, northern Red Sea, we examined patterns of abundance and clonal replication in R. rhodostoma in order to understand the modes and rates of spread of polyps across the reef flat. Polyps were abundant on the inner reef flat (maximum 1510 polyps m,2 and 69% cover), rare on the outer reef flat, and completely absent on the outer reef slope at >3 m depth. Individuals cloned throughout the year via 3 distinct modes: longitudinal fission, inverse budding, and marginal budding. Marginal budding is a replicative mode not previously described. Cloning mode varied significantly with polyp size. Approximately 9% of polyps cloned each month, leading to a clonal doubling time of about 1 year. The rate of cloning varied seasonally and depended on day length and seawater temperature, except for a brief reduction in cloning during midsummer when polyps spawned gametes. Polyps of R. rhodostoma appear to have replicated extensively following a catastrophic low-tide disturbance in 1970, and have become an alternate dominant to stony corals on parts of the reef flat. [source] Sexual reproduction in the tropical corallimorpharian Rhodactis rhodostomaINVERTEBRATE BIOLOGY, Issue 4 2000Nanette E. Chadwick-Furman Abstract. Polyps of the tropical corallimorpharian Rhodactis rhodostoma segregate sexes between center and edge positions within aggregations produced by clonal replication. On a reef flat at Eilat, northern Red Sea, infertile polyps and males occur mainly along the edges of clonal aggregations, while females mostly occupy central positions within each aggregation. In addition, on the inner to middle reef flat where polyps of this species are abundant, aggregations consist mostly of females. On the outer reef flat, where polyps are rare, a sampled aggregation consisted mostly of males and infertile polyps. Male polyps are significantly smaller than females, and the smallest polyps are infertile. Fecundity increases significantly with polyp size in females, but testis size and number do not vary with body size in males. Oocytes are present in polyps during most of the year and gradually increase in size until annual spawning in June-July during the period of maximum day length. Testes do not vary significantly in size during the year and remain a small proportion of body mass (>8%). In contrast, females invest up to 30% of their body mass into gonads during the months immediately before spawning. The annual spawning of gametes coincides with a temporary drop in the frequency of clonal replication by polyps. We estimate that each female polyp of R. rhodostoma may release up to 3000 large eggs (500 ,m in maximum diameter) each summer. The high investment of this corallimorpharian in sexual production of planktonic propagules may allow rapid dispersal to reef habitats distant from parent populations. [source] Age and growth of the Randall's threadfin bream Nemipterus randalli (Russell, 1986), a recent Lessepsian migrant in Iskenderun Bay, northeastern MediterraneanJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2010D. Erguden Summary Randall's threadfin bream, Nemipterus randalli, first recorded in Iskenderun Bay in Turkey in 2008, seems to have increased in the region. The species, widespread in the western Indian Ocean and with a rapid expansion, appears to have migrated to the bay via the Red Sea. Although its presence in the region has been published, there has been little or no information as to age and growth parameters of this Lessepsian migrant in its new habitat. The present study aims to determine the basic age and growth parameters of the species colonized in the region. A total of 379 collected individuals were studied from November 2007 to October 2008. Total specimen lengths ranged from 4.80 to 21.50 cm, and weights from 1.10 to 138.36 g. Maximum age was 3 years for both sexes. The length,weight relationship was described as W = 0.0011 × L3.061 (r2 = 0.982). The von Bertalanffy growth parameters were: L, = 34.96 cm; K = 0.214 year,1; t0 = ,1.244 year for the entire population. These data were compared with results from studies made in other geographic areas. [source] Absence of post-Miocene Red Sea land bridges: biogeographic implicationsJOURNAL OF BIOGEOGRAPHY, Issue 6 2006Carlos A. Fernandes Abstract In a large number of studies concerned with species movements between Africa and Eurasia, including the migrations of hominids out of Africa, a frequently-cited dispersal route is across a hypothetical land bridge in the southern Red Sea, which is suggested to have emerged during glacial sea-level lowstands. This paper, however, unequivocally demonstrates that palaeoceanographic and palaeoecological data are incompatible with the existence of Red Sea land bridges since the Miocene. The case is made by presenting the first quantitative history of water depth above the Red Sea sill for the last 470,000 years, a time period that includes the four most recent glacial,interglacial cycles, and by discussing the predictable consequences of any land bridge formation on the Red Sea sedimentary and microfossil records. The absence of post-Miocene Red Sea land bridges has extensive implications for biogeographic models in the Afro-Arabian region. Genetic, morphometric and palaeontological patterns reported in the literature cannot be related to dispersals over a land bridge, or in the case of marine organisms, separation of the Red Sea from the Indian Ocean by a land bridge. If such patterns in terrestrial species are only congruent with a southern Red Sea dispersal route, then they need to be considered in terms of sweepstake rafting, anthropogenic introduction, or in the particular case of the Out-of-Africa migration by modern humans, seafaring. The constraints imposed by our palaeoenvironmental record on biogeographic reconstructions within and around the Red Sea will hopefully encourage both the review of previous works and the preference for multidisciplinary approaches in future studies. [source] First record of Apogon queketti Gilchrist (Osteichthyes: Apogonidae) in the Mediterranean SeaJOURNAL OF FISH BIOLOGY, Issue 4 2006L. Eryilmaz The spotfin cardinalfish Apogon queketti is recorded for the first time in the north-eastern Mediterranean Sea (Iskenderun Bay, Turkey). Two specimens of this species, 111 and 102 mm total length were caught by a commercial trawler at depths of 55 and 60 m on 14 October 2004 and 23 April 2005, respectively. The occurrence of this species in the Mediterranean Sea is the result of migration from the Red Sea via the Suez Canal. [source] Cytomorphological alterations of the thymus, spleen, head-kidney, and liver in cardinal fish (Apogonidae, Teleostei) as bioindicators of stressJOURNAL OF MORPHOLOGY, Issue 1 2006Lev Fishelson Abstract Morphological and cytological alterations at the light microscope (LM) and transmission electron microscope (TEM) levels were observed in the thymus, spleen, head-kidney, and liver of cardinal fishes (Apogonidae, Teleostei) from the Gulf of Aqaba, Red Sea, sampled from a strongly polluted site at the northern end of the gulf, and compared to similar samples from a clean, reference site. At the polluted site, the most prominent change was the formation of numerous deposits of cells rich in phagosomes with lipofucin, melanin granules, and phagocytosed debris, including a high increase in number and dimensions of Hassall's corpuscles and melano-macrophage centers. The number of Hassall's corpuscles was 20 (±8.0)/mm2 and of melano-macrophage centers 18 (±4.0)/mm2 at the polluted site, and 7.0 (±4.0)/m2 vs. 5.0 (±2.0)/mm2 respectively at the reference site. In numerous instances the head kidney's melano-macrophage centers in fishes from the polluted site were encapsulated by reticulocytes, a phenomenon recognized as a marker of neoplasmosis and possible malignancy. In the spleens of fishes from the polluted site, numerous deposits of cell debris, peroxisomes, and enlarged lysosomes were also observed. The livers (hepatopancreas) of fishes from polluted waters demonstrated very strong hyperlipogeny. Many of their hepatocytes were laden with lipid vesicles, fragmented endoplasmic reticulula, and aberrant mitochondria. Although the observed alterations in the glands and liver do not indicate any immediate threat to the life of the fish, they can become crucial with respect to energy turnover and fecundity trajectories. This study strongly suggests the use of cytological alterations in vital organs, such as were observed, as pathological biomarkers to environmental stress. J. Morphol. © 2005 Wiley-Liss, Inc. [source] A mitochondrial phylogeography of Brachidontes variabilis (Bivalvia: Mytilidae) reveals three cryptic speciesJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 4 2007M. Sirna Terranova Abstract This study examined genetic variation across the range of Brachidontes variabilis to produce a molecular phylogeography. Neighbour joining (NJ), minimum evolution (ME) and maximum parsimony (MP) trees based on partial mitochondrial DNA sequences of 16S-rDNA and cytochrome oxidase (COI) genes revealed three monophyletic clades: (1) Brachidontes pharaonis s.l. from the Mediterranean Sea and the Red Sea; (2) B. variabilis from the Indian Ocean; (3) B. variabilis from the western Pacific Ocean. Although the three clades have never been differentiated by malacologists employing conventional morphological keys, they should be ascribed to the taxonomic rank of species. The nucleotide divergences between Brachidontes lineages (between 10.3% and 23.2%) were substantially higher than the divergence between congeneric Mytilus species (2.3,6.7%) and corresponded to interspecific divergences found in other bivalvia, indicating that they should be considered three different species. Analysis of the 16S-rDNA sequences revealed heteroplasmy, indicating dual uniparental inheritance (DUI) of mtDNA in the species of Brachidontes collected in the Indian Ocean, but not in the species in the Pacific nor in the species in the Red Sea and the Mediterranean Sea. When we employed the conventional estimate of the rate of mitochondrial sequence divergence (2% per million years), the divergence times for the three monophyletic lineages were 6,11 Myr for the Indian Ocean and Pacific Ocean Brachidontes sp. and 6.5,9 Myr for the Red Sea and Indian Ocean Brachidontes sp. Thus, these species diverged from one another during the Miocene (23.8,5.3 Myr). We infer that a common ancestor of the three Brachidontes species probably had an Indo-Pacific distribution and that vicariance events, linked to Pleistocene glaciations first and then to the opening of the Red Sea, produced three monophyletic lineages. Riassunto Lo studio filogeografico è stato condotto su tutto l'areale di Brachidontes variabilis (Krauss, 1848) attraverso l'analisi di sequenze mitocondriali (16S-rDNA e COI) che hanno separato i campioni in tre cladi monofiletici. Diversi algoritmi (NJ, ME e MP) hanno elaborato alberi con la stessa topologia, in cui è possibile riconoscere: (1) Brachidontes pharaonis s.l. dell'area Mar Mediterraneo , Mar Rosso; (2) Brachidontes variabilis dell' Oceano Indiano; (3) Brachidontesvariabilis dell'Oceano Pacifico. Il loro grado di divergenza è sufficientemente alto da potere ascrivere al rango di specie i singoli cladi, nonostante non siano stati ancora individuati i caratteri tassonomici distintivi, a causa della grande variazione morfologica. La divergenza nucleotidica tra le tre linee di Brachidontes era compresa tra 10.3% e 23.2%, in un range di valori superiori a quelli trovati nel confronto tra specie congeneriche di Mytilus sp (2.3,6.7%). Utilizzando il tasso evolutivo, che convenzionalmente viene applicato ai valori di divergenza genetica di geni mitocondriali (2% per milioni di anni), si sono ricavati tempi di divergenza corrispondenti a 6,11 milioni di anni tra Oceano Indiano e Pacifico, e a 6.5,9 milioni di anni tra Mar Rosso e Oceano Indiano. Le tre linee evolutive sembrano essersi separate durante il Miocene. Probabilmente un comune antenato con distribuzione Indo-Pacifica può essere andato incontro a processi di vicarianza e/o di dispersione legati alle glaciazioni pleistoceniche prima e all'apertura del Mar Rosso dopo. [source] First record of Palisada maris-rubri (Ceramiales, Rhodophyta) from the Mediterranean Sea along with three proposed transfers to the genus PalisadaPHYCOLOGICAL RESEARCH, Issue 1 2010Donatella Serio SUMMARY The first occurrence of Palisada maris-rubri (K.W. Nam et Saito) K.W. Nam (Ceramiales, Rhodomelaceae) from the Mediterranean Sea, is reported. To date the species was known only from tetrasporic specimens from the type locality (Ras Muhammed, Sinai, Egypt, Red Sea). Mediterranean thalli share nearly all vegetative and reproductive features with Red Sea specimens showing more robust thalli with axes to 3 mm broad and ultimate branchlets to 1000 µm broad, absence of intercellular spaces between medullary cells and epidermal cells in transverse section with a palisade arrangement. Male and cystocarpic thalli are recorded for the first time. Moreover, the analysis of characters of three species of Chondrophycus previously known from the Mediterranean Sea (C. patentirameus (Montagne) K.W. Nam, C. tenerrimus (Cremades) G. Furnari et al. and C. thuyoides (Kützing) G. Furnari) led us to conclude that they belong to the genus Palisada. The following new combinations are formally proposed: P. patentiramea (Montagne) Serio et al., P. thuyoides (Kützing) Serio et al., P. tenerrima (Cremades) Serio et al. [source] Isolation and characterization of the "zooxanthellae" from soritid foraminifera and the giant clam Tridacna maximaTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 2 2005JOHN J. LEE Various methodological approaches are being used to characterize Symbiodinium spp isolated from Marginopora vertebralis and Amphisorus hemprichii and Amphisorus sp. from the Indo-pacific. While most of the cells in culture are non-motile vegetative cells, dinospores occur in batch cultures. We find consistant variance among the isolates in the duration and time of appearance of motile forms. Nitrate (0.146 mM) supports higher populations of the isolates than NH4 (0.146 mM). Higher concentrations of NH4 inhibit growth. Although Fensome et al. (1993) characterized the Order Suessiales (and Family Symbiodiniaceae) as gymnnodiniphycideans in which the amphiesmal vesicals are arranged in 7,10 longitudinal series we were unable to detect any plates on the surfaces of our isolates in the SEM. We were unsuccessful in revealing plates on non-motile forms by freeze fracture but they were present after treatment with various chemical agents (e.g. H2O2, HOCl,) and enzymes (cellulase, chitinase). They are not polygonal or arranged in the patterns anticipated for the Symbiodiniaceae. Polyclonal antibody studies of the Symbiodinium -like isolates are in agreement with molecular systematic studies in the sense that there is a common relation. The foram endosymbiotic dinoflagellates share some common surface antigens with each other and with the few invertebrate isolates we have tested. Studies of the foraminiferal symbionts' plastids revealed considerable morphological diversity. We isolated a diversity of endosymbionts from the mantle of Tridacna maxima from the Red Sea and the Marshall Islands. These included Symbiodinium, Amphidinium, Tetraselmis, and an unidentified chlorophyte. [source] Comprehensive review of the records of the biota of the Indian Seas and introduction of non-indigenous speciesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2005D.V. Subba Rao Abstract 1.Comparison of the pre-1960 faunal survey data for the Indian Seas with that for the post-1960 period showed that 205 non-indigenous taxa were introduced in the post-1960 period; shipping activity is considered a plausible major vector for many of these introductions. 2.Of the non-indigenous taxa, 21% were fish, followed by Polychaeta (<11%), Algae (10%), Crustacea (10%), Mollusca (10%), Ciliata (8%), Fungi (7%), Ascidians (6%) and minor invertebrates (17%). 3.An analysis of the data suggests a correspondence between the shipping routes between India and various regions. There were 75 species common to the Indian Seas and the coastal seas of China and Japan, 63 to the Indo-Malaysian region, 42 to the Mediterranean, 40 and 34 to western and eastern Atlantic respectively, and 41 to Australia and New Zealand. A further 33 species were common to the Caribbean region, 32 to the eastern Pacific, 14 and 24 to the west and east coasts of Africa respectively, 18 to the Baltic, 15 to the middle Arabian Gulf and Red Sea, and 10 to the Brazilian coast. 4.The Indo-Malaysian region can be identified as a centre of xenodiversity for biota from Southeast Asia, China, Japan, Philippines and Australian regions. 5.Of the introduced species, the bivalve Mytilopsis sallei and the serpulid Ficopomatus enigmaticus have become pests in the Indian Seas, consistent with the Williamson and Fitter ,tens rule'. Included amongst the biota with economic impact are nine fouling and six wood-destroying organisms. 6.Novel occurrences of the human pathogenic vibrios, e.g. Vibrio parahaemolyticus, non-01 Vibrio cholerae, Vibrio vulnificus and Vibrio mimicus and the harmful algal bloom species Alexandrium spp. and Gymnodinium nagasakiense in the Indian coastal waters could be attributed to ballast water introductions. 7.Introductions of alien biota could pose a threat to the highly productive tropical coastal waters, estuaries and mariculture sites and could cause economic impacts and ecological surprises. 8.In addition to strict enforcement of a national quarantine policy on ballast water discharges, long-term multidisciplinary research on ballast water invaders is crucial to enhance our understanding of the biodiversity and functioning of the ecosystem. Copyright © 2005 John Wiley & Sons, Ltd. [source] Towards the earliest history of KindaARABIAN ARCHAEOLOGY AND EPIGRAPHY, Issue 1 2009M.D. Bukharin In the second century AD Rome could not protect the caravan trade in north-west Arabia to the south of Dedan with its own military detachments, stationed in Mad,'in and al-'Ul,. Rome seems to have attracted Aksum for the subjugation of the Arab nomads of north-west Arabia and protection of the ,Incense Road'. At the end of the second century AD Rome, Aksum and Saba' shared common interests: Aksum helped Rome to restore peace on the caravan routes, in which Saba' seemed to have been interested as well, and Rome provided a market for East African and South Arabian products. During the west Arabian campaign, described in the inscription RIÉ 277 (Monumentum Adulitanum II), which is to be dated to the very end of the second century AD, the unnamed Aksumite king, presumably Gad,rat, conquered the lands of Kinaidokolpites and Arrabites. The former name represents a combination of two names, the first of which seems to be derived from the name of Kinda (identification of the entire name with Kinda is taken for ,somewhat unlikely' in Retsö 2003: 450, n. 60). The Kinda seem to have been also known in the earlier classical tradition under the name of Kanraitai , the inhabitants of Ghamr dh,-Kinda , and thus were the most aggressive and dangerous obstacle for the Roman traders on the land routes in north-west Arabia and in the northern Red Sea in the first,second century AD. The Aksumite invasion forced the resettlement of the Kinda on the other branch of the ,Incense road', through modern Qaryat al-F,w , and its blockade, consequently followed at the beginning of the third century by the campaigns of the Sabaean king ,,'ir ,Awtar against them. [source] LEAD ISOTOPE ANALYSES OF BRONZE AGE COPPER-BASE ARTEFACTS FROM AL-MIDAMMAN, YEMEN: TOWARDS THE IDENTIFICATION OF AN INDIGENOUS METAL PRODUCTION AND EXCHANGE SYSTEM IN THE SOUTHERN RED SEA REGION,ARCHAEOMETRY, Issue 4 2009L. WEEKS The results of the lead isotope analysis (LIA) of 15 copper-base artefacts from the Bronze Age site of al-Midamman, Yemen, are reported. The LIA data suggest the existence of an indigenous Bronze Age metal production and exchange system centred on the southern Red Sea region, distinct from those in neighbouring regions of Arabia and the Levant. These preliminary results are highly significant for the archaeology of the region, suggesting that local prehistoric copper extraction sites have thus far gone unrecorded, and highlighting the need for systematic archaeometallurgical fieldwork programmes in the countries surrounding the southern Red Sea. [source] | ||||||||||||||||