Southwestern Arabia Research Articles

Two Anthropomorphic Stelae Connected With a Platform‐Like Structure in the Area of Ḥimā (Saudi Arabia): New Data From Southwestern Arabia

ABSTRACTSince 2020, the Saudi‐French Archaeological and Epigraphic Mission to Najrān (MAFSN) has been conducting additional archaeological surveys and small‐scale excavations in the Ḥimā area, providing a wealth of data from different historical periods. Preliminary analysis of the structures and artefacts discovered revealed a complex landscape characterised by patterns of continuous human activity from the Palaeolithic to modern times, underlining the historical importance of this area as a transit hub along the caravan routes. The identification of various structures has made it possible to establish a basic typology and enabled a distribution study of the human presence, allowing comparisons with neighbouring regions. This paper presents the discovery of two anthropomorphic stelae associated with a platform‐like structure excavated in November 2021 on the eastern side of Jabal al‐Kawkab, al‑Gharaziyyāt area. The documentation of these stelae lays the groundwork for a re‐evaluation of the Bronze Age occupation of the area.

A multi‐analytical approach applied to pottery from Oman as a key to understanding ancient Indian Ocean maritime trade

AbstractThe populations in Sumhuram (third/second century bce to fifth century ce) and Hamr al‐Sharqiya 1 (HAS1) (first millennium bce to first/second century ce) were involved in one of the most important examples of large‐scale trade systems in antiquity: the maritime network connecting the coasts of the Indian Ocean. This research focuses on a total of 35 southwestern Arabian and Indian pottery sherds from both the settlements of Sumhuram and Hamr al‐Sharqiya 1, analysed through a multi‐analytical complementary approach. This study intends to test the input potential of this type of approach applied to ceramics in the context of the Indian Ocean trade network. The techniques adopted are powder X‐ray diffraction, optical microscopy, inductively coupled plasma–mass spectrometry and scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy. The results obtained allow the identification of eight distinct groups, each characterized by unique (textural, mineralogical, geochemical) signatures, providing specific clues for determining their provenance, specifically from the Indian subcontinent and southwestern Arabia. This paper shows the importance of this type of archaeometric study that must be integrated into a transdisciplinary approach.

Settlement Discontinuities in Southwestern Arabia during the Middle and Late Holocene: The Bayḥān (Yemen) Region

ABSTRACT Recent research has produced an increasingly nuanced but still incomplete understanding of Neolithic through Iron Age communities in southwestern Arabia. Present evidence indicates that foraging communities in the lowland interior of Yemen adopted animal herding during the 6th millennium b.c. and irrigation farming during the 3rd millennium b.c. or possibly earlier. Survey in the Wādī Bayḥān area has identified multiple settlement discontinuities. Prehistoric structures in Wādī Ṣurbān reflect episodic occupation, probably by Bronze Age pastoralists. Geomorphological evidence for Bronze Age irrigation systems appears in large valleys; these systems continued into the Iron Age and developed in small valleys. Geomorphological and archaeological evidence suggests an occupation hiatus around 700 b.c. in some larger valleys such as Wādī Ḍurā’. Settlement discontinuities seem to have responded to abrupt climate fluctuations and to regional political history.

Demonstratives in Musandam Arabic: Distinctive Archaisms and Innovations

Abstract This study introduces and analyzes proximal and distal singular demonstratives in fourteen varieties of Musandam Arabic, a little-documented dialect group located on Musandam Peninsula in northern Oman and neighbouring areas of the United Arab Emirates. Following an overview of the dialect group in its regional context, the study provides a description of singular demonstratives from the point of view of phono-logy, morphology, and geographical distribution. The study then focuses on two salient features found in several of the varieties under investigation: gender distinction based on consonantal alternation (d-based masculine forms vs t-based feminine forms); and gemination of the feminine t-element. While the former is attested, albeit rarely, in other Arabic dialects, the latter is unheard of. In the last section of the article, some hypotheses are put forward as to how these forms could have developed from a historical point of view, in light of data from different Arabic and Semitic varieties. While the gemination of the t-element is best regarded as a Musandam-internal innovation, the d : t consonantal alternation reinforces the putative historical link between south-western Arabia and Oman.

Diversification of Hemidactylus geckos (Squamata: Gekkonidae) in coastal plains and islands of southwestern Arabia with descriptions and complete mitochondrial genomes of two endemic species to Saudi Arabia

Diversification of Hemidactylus geckos (Squamata: Gekkonidae) in coastal plains and islands of southwestern Arabia with descriptions and complete mitochondrial genomes of two endemic species to Saudi Arabia

Exploring the association between khat use and psychiatric symptoms: a systematic review

ObjectivesConsumption of the drug khat is high across East Africa and the South-Western Arabian Peninsula despite evidence for its adverse psychiatric effects. This systematic review aims to explore cross-sectional research...

Ichthyodiversity in southeastern Arabian Peninsula: Annotated checklist, taxonomy, short description and distribution of Inland fishes of Oman.

Oman, a country in Southwest Asia, situated on the southeastern quarter of the Arabian Peninsula presents a high level of biological diversity especially marine elements. Although arid habitats cover most parts of Oman (82%), the region has several freshwater systems that are vital for the survival of people as well as for different groups of animals and plants. Research works on Oman biodiversity including terrestrial and marine, have been steadily increasing over the last few decades, but freshwater ecosystems have not been well investigated. Oman comprises parts of three freshwater ecoregions including the Oman Mountains, Southwestern Arabian Coast, and Arabian Interior having xeric freshwaters and endorheic (closed) basins which support a variety of inland fishes. The current checklist provides for each species of inland waters of Oman all recognized and named taxa, documenting recent changes and controversies in nomenclature, its records, taxonomic status, synonyms, etymology, common English name, short description, range expansion, and detailed distribution map based on several field surveys throughout the country. We also provide native, endemic, and introduced species. The diversity of inland fishes of Oman included in this annotated checklist consists of 23 recognized species in 15 genera, 10 families, seven orders, and a class. Also, for the first time, we report and confirm the presence of four species in the inland waters of Oman. The most diverse order is Cypriniformes (nine species, 39.13%), followed by Gobiiformes (six species, 26.09%), Cyprinodontiformes (three species, 13.04%), Cichliformes (two species, 8.69%), and Centrarchiformes, Gonorynchiformes and Mugiliformes (one species, 4.35% each). 21 native species (91.3%) in nine families and two exotic species (8.7%) in two families are listed here. Out of 21 native species, eight species (16.8%) in two families are endemic elements that are restricted to the Oman territory only. Identification of all recognized species was confirmed by DNA barcoding (mitochondrial COI). Oman Mountains Ecoregion (OME), Southwestern Arabian Coast Ecoregion (SACE), and Arabian Interior Ecoregion (AIE) harbor 15, 12, and one species, respectively. The provided data will be necessary for increasing the fish knowledge, the development of competent and pragmatic management plans and effective conservation policies.

Recent Climatology (1991-2020) and Trends in Local Warm and Cold Season Extreme Temperature Days and Nights in Arabia.

The Arabian Peninsula (Arabia) is among the places to have experienced the greatest amount of warming during recent decades, and this trend is projected to continue. Specifics related to the characteristics (frequency, duration, and intensity) of extreme temperature events (ETEs) over Arabia as a whole are either largely outdated or limited only to specific areas. The seasonal ETE definitions commonly used in local studies are neither climatological- nor phenomenon-based. Using a novel and straightforward framework, the seasons of four extreme temperature types (extreme warm days/nights (EWDs/EWNs) and extreme cold days/nights (ECDs/ECNs)) were identified on the simultaneous basis of event occurrence and impact times. Assessments of ETE frequency, duration, and intensity and their recent changes were then provided based on the most recent climate data (1991–2020). Results showed that the use of traditional seasonal definitions (e.g., meteorological seasons) tends to assume a spatiotemporal homogeneity in the seasonality of ETEs and their potential risk levels throughout the year. The developed framework distinguished months with events that have larger potential impacts together with their local seasons. ETE seasons were found to vary at the regional and local scales and are better defined at both the local and phenomenon levels. Early extreme warm events were hotter, and those at locations with longer local warm seasons demonstrated higher intensities. ECDs tended to be more frequent at coastal locations, whereas ECNs were more frequent over southwestern Arabia. Early and late extreme cold events were much colder than those occurring mid-season. Trend analyses revealed generally increasing regional trends in the frequency of extreme warm events, whereas extreme cold events have declined. The duration (i.e., consecutive occurrences) and intensity of EWNs have been increasing at more locations, suggesting that urgent attention is needed within such an arid and hot climate type in which nighttime stress relief is already very limited.

Decadal shift of the influence of Arctic Oscillation on dust weather frequency in spring over the Middle East during 1974–2019

AbstractDust weather has an impact on human health and climate change in the Middle East. In this study, we examined the influence of the Arctic Oscillation (AO) on spring dust weather frequency over the Middle East at an interannual timescale during 1974–2019. The results show that there was an interdecadal shift of the influence of AO on dust weather frequency in the Middle East, with a correlation coefficient between the AO index and dust weather frequency changing from −0.52 during 1974–1994 period (P1) to 0.49 during 1995–2013 period (P2). During P1, negative correlations between AO index and dust weather frequency were found over the northern Arabian Peninsula, and during P2, positive ones were mostly over the central and southwestern Arabian Peninsula. In the lower and middle troposphere, negative geopotential height anomalies are associated with the negative phase of the AO over South Europe during P1, whereas negative geopotential height anomalies are associated with the positive phase of the AO over Northeast Africa during P2. The negative height anomalies resulted in the occurrence of more low‐pressure systems and, thus, dust weather in the Middle East. It is found that the interdecadal shift of the influence of the AO on dust weather was related to an AO‐related northward displacement of wave train propagation during P2. Specifically, during P1 period, the northern branch of AO‐related wave train dominated over the middle latitudes of the North Atlantic across South Europe to the Arabian Peninsula, which resulted in the negative height anomaly over South Europe in the lower and middle troposphere. However, during P2 period, the AO‐related wave train propagation moved northward, and then, the southern branch of the AO‐related wave train dominated over the low latitudes of the North Atlantic across northern Africa to the Arabian Peninsula, which played an important role in the formation of the negative height anomalies over Northeast Africa.

Representation of Arabian Peninsula summer climate in a regional atmospheric model using spectral nudging

This study assesses the performance of the Weather Research and Forecasting (WRF) model in simulating the Arabian Peninsula summer climate for the period 2001–2016. The European Centre for Medium range Weather Forecast (ECMWF) reanalysis is downscaled using WRF without (CTRL) and with the Spectral Nudging (SPN) method. Our results suggest that the noticeable cold biases in surface temperatures (mean, minimum, and maximum) over the Arabian Peninsula in CTRL are significantly reduced in SPN. The seasonal patterns of surface pressure, cloud cover, lower and upper tropospheric circulation, and mid-tropospheric anticyclone are also simulated more realistically with SPN. The evaluation of mean vertical profiles of dynamical and thermo-dynamical features over the Arabian Peninsula further confirms the enhanced simulations with SPN with respect to CTRL. Though SPN captures better the observed evolution of rainfall compared to that of CTRL, it produces a positive rainfall bias over the Southwestern Arabian Peninsula. Stronger vertical motions associated with the local topography enhance the higher water vapor loading, condenses in the upper layers, and results in excess amount of rainfall in SPN. Furthermore, with SPN, WRF is further able to better simulate the synoptic features of heat waves. Overall, SPN enhances WRF simulation skill of the horizontal structures and vertical profiles of the Arabian Peninsula summer climate by enforcing a better balance between the small and large scale features and associated feedbacks.

Correction: Reanalysis of the 2000 Rift Valley fever outbreak in Southwestern Arabia

[This corrects the article DOI: 10.1371/journal.pone.0233279.].

Reanalysis of the 2000 Rift Valley fever outbreak in Southwestern Arabia.

The first documented Rift Valley hemorrhagic fever outbreak in the Arabian Peninsula occurred in northwestern Yemen and southwestern Saudi Arabia from August 2000 to September 2001. This Rift Valley fever outbreak is unique because the virus was introduced into Arabia during or after the 1997-1998 East African outbreak and before August 2000, either by wind-blown infected mosquitos or by infected animals, both from East Africa. A wet period from August 2000 into 2001 resulted in a large number of amplification vector mosquitoes, these mosquitos fed on infected animals, and the outbreak occurred. More than 1,500 people were diagnosed with the disease, at least 215 died, and widespread losses of domestic animals were reported. Using a combination of satellite data products, including 2 x 2 m digital elevation images derived from commercial satellite data, we show rainfall and potential areas of inundation or water impoundment were favorable for the 2000 outbreak. However, favorable conditions for subsequent outbreaks were present in 2007 and 2013, and very favorable conditions were also present in 2016-2018. The lack of subsequent Rift Valley fever outbreaks in this area suggests that Rift Valley fever has not been established in mosquito species in Southwest Arabia, or that strict animal import inspection and quarantine procedures, medical and veterinary surveillance, and mosquito control efforts put in place in Saudi Arabia following the 2000 outbreak have been successful. Any area with Rift Valley fever amplification vector mosquitos present is a potential outbreak area unless strict animal import inspection and quarantine proceedures are in place.

Burrowing crabs in arid mangrove forests on the southwestern Arabian Gulf: Ecological and biogeographical considerations

Many species of mangrove crabs are essential in the formation of mangrove ecosystems, and the bioturbation resulting from the excavation of their underground chambers is directly correlated with substrate oxygenation and carbon and nitrogen cycling within the ecosystem. This study examines the ecological and biogeographical characteristics of bioengineering crab assemblages that inhabit the environmentally challenging arid mangroves in the southwestern Persian-Arabian Gulf. Results demonstrated that a hyper-arid environment could directly impact crab diversity, reducing it to only one species per niche or coastal zone. A biogeographic comparison revealed an exclusive divergence of species composition in each Gulf region. Variations in seasonal temperatures were found to have a direct influence on the abundance of species and how the zonation is driven by sediment composition and trophic relations. Two crabs – Nasima dotilliformis in the salt march (supratidal zone) and Macrophthalmus (Mareotis) depressus in the intertidal – were considered to be the most influential functional species for this hyper-arid ecosystem due to their abundance, size, bioturbation potential and niche specificity for the intertidal zone. The limited number of species within the arid mangrove system emphasised the biogeographic pressure and inherent importance of the few active bioengineering species present and adapted to the harsh conditions, indicating that the dominant crabs within the biotope are directly related to the successful evolutionary establishment of these hyperarid mangroves. The study highlights important implications for future forest management strategies of the only forest ecosystem that tolerates the extremes of the southwestern Persian-Arabian Gulf area.

The first proven oxychilid land snail endemic to China (Eupulmonata, Gastrodontoidea).

A new and the first proven oxychilid species endemic to China is reported from Sichuan Province. Sinoxychilusgen. nov. is established based on this new species and has diagnostic traits of the sculptured protoconch, partial epiphallus wrapped by developed penis sheath, penial retractor muscle inserting on the top of penial caecum, spinelets on penial pilasters, absence of epiphallic papilla and perivaginal gland present on vagina and proximal bursa copulatrix duct. In light of shell morphology and through geometric morphometric analyses, Zonites scrobiculatus scrobiculatus Gredler and Z. scrobiculatus hupeina Gredler are proposed to be included in the new genus. A phylogenetic inference based on ITS2 gene indicates that the new genus is systematically close to Oxychilus Fitzinger, which is known from the Western Palearctic and the Southwestern Arabian Peninsula, regions that are geographically far from the distribution range of the new genus.

Shear Velocity Structure Beneath Saudi Arabia From the Joint Inversion of P and S Wave Receiver Functions, and Rayleigh Wave Group Velocity Dispersion Data

AbstractWe develop a new 3‐D shear velocity model for the lithosphere and sublithospheric mantle under Saudi Arabia by jointly inverting P wave receiver functions, S wave receiver functions, and fundamental‐mode Rayleigh wave group velocities. P and S receiver functions are calculated from earthquakes recorded between 2012 and 2015 at 156 Saudi National Seismic Network stations operated by the Saudi Geological Survey. Rayleigh wave dispersion data are extracted from independent tomographic studies. Our model reveals significant lateral variations in crustal and upper‐mantle S velocity below Saudi Arabia. Particularly, a low‐velocity zone, with minimum S velocity of ~4.0 km/s in the depth range of 70‐190 km, is observed under the Arabian Shield coinciding with Cenozoic surface volcanism. The low‐velocity zone is found consistent with the presence of partial melts in the mantle and interpreted as a potential deep magma source for the volcanism in western Arabia. We propose that magmas responsible for the Arabian volcanism may be derived from multiple sources. Both lithospheric thinning and the Afar plume trigger magma production beneath southwestern Arabia, while decompression melting caused by the lithospheric thinning may be the main factor in the central and northern portions. Furthermore, we find evidence for localized crustal low shear velocity anomalies (2–4% reductions) that appear spatially correlated to the volcanism; these may be due to fractures caused by magma ascent and small amounts of partial melt in the crust. This spatial distribution of S velocity reductions may indicate the plumbing system for magma ascent underneath western Arabia.

Systematics of the Mesalina guttulata species complex (Squamata: Lacertidae) from Arabia with the description of two new species.

Mesalina are small diurnal lacertid lizards inhabiting arid areas from North Africa to northwestern India. Previous phylogenetic studies have shown the existence of several species complexes within the genus, some of them with high levels of undiscovered diversity. In the present study, we carry out an integrative systematic revision of the Mesalina guttulata species complex using both molecular and morphological data from across its entire distribution range in North Africa, the Middle East and Arabia. The results of the genetic analyses indicate that M. guttulata and M. bahaeldini are two allopatric sister taxa separated by the Suez Canal and that the species complex includes a further three unnamed deep phylogenetic lineages, two of them restricted to southern and southwestern Arabia and described herein as Mesalina austroarabica sp. nov. and Mesalina arnoldi sp. nov., respectively. As a result of the lack of enough material, the third deep lineage, distributed across Kuwait, Saudi Arabia and Jordan, is provisionally left undescribed. The two newly described species are characterized by their size, scale counts and tail coloration, as well as differences at the three mitochondrial and one nuclear gene analyzed in the present study.

ENSO relationship to summer rainfall variability and its potential predictability over Arabian Peninsula region

The El Niño Southern Oscillation (ENSO) phenomenon is considered to be responsible for rainfall predictability in many regions. Some of its regional teleconnections, such as over the Arabian Peninsula in boreal summer (June–August) season, are not well studied. Therefore, in this paper, the relationship between the summer seasonal mean rainfall and ENSO is analyzed with the aid of a 15-member ensemble of simulations using the Saudi-King Abdulaziz University (KAU) Atmospheric Global Climate Model (AGCM) for the period 1981–2015. The southwestern peninsula rainfall is linked to the Sea Surface Temperature (SST) anomalies in the central-eastern pacific region. This relationship is established through an atmospheric teleconnection which shows upper-level convergence anomalies over the southern Arabian Peninsula compensating the central-eastern Pacific upper-level divergence anomalies for the warm ENSO phase, and vice-versa for the cold Phase. The upper-level convergence over the southern Arabian Peninsula leads to sinking motion, low-level divergence and consequently to reduced rainfall in the warm phase, while reverse happens in the cold phase. The correlation coefficient between the observed area-averged Niño3.4 index and a Southwestern Arabian Peninsula Rainfall Index (SARI) is −0.43 (statistically significant at 95%). Overall, model shows a potential predictability (PP) of 0.53 for the SARI region. Predictability during El Niño is higher than during La Niña events. This is not only because of a stronger signal, but also noise reduction contributes to the increase of PP in El Niño compared to that of La Niña years.

A large handaxe from Wadi Dabsa and early hominin adaptations within the Arabian Peninsula

Abstract

Khat promotes human breast cancer MDA-MB-231 cell apoptosis via mitochondria and MAPK-associated pathways

Khat (Catha edulis Forsk) is a flowering evergreen plant in Eastern Africa and Southwestern Arabia. Consumption of Khat has been associated with the development of oral cancer, but its mechanism of action on the molecular level remains unclear. The present study demonstrated the cytotoxic effect of khat extracts on the human breast cancer cell line MDA-MB-231. Trypan blue exclusion assays, flow cytometry, fluorescent and electron microscopy, as well as western blotting were used to analyze the effects of Khat on the cell viability of breast cancer cells, expression of apoptotic-associated proteins and the levels of reactive oxygen species (ROS). The results of the present study demonstrated that treatment with 400 µg/ml khat was able to induce cell death in breast cancers, with an increase in the protein expression of apoptosis regulator Bax and a decrease in the expression of B-cell lymphoma 2, along with a decrease in ROS levels in a time-dependent manner. Furthermore, the expression of activated c-Jun N-terminal and extracellular regulated protein kinases was increased in khat-treated cells compared with untreated cells. Mitochondria participated in cell apoptosis through the release of apoptogenic proteins to the cytosol and the generation of excess reactive oxygen species. The results of the present study suggest that khat induces MDA-MB-231 cell apoptosis via MAPK activation and mitochondrial-mediated death.

Origin and mechanism of formation of the Oligo-Miocene ironstones of Umm Himar Formation, Turabah area, southwestern Arabian Shield, Saudi Arabia

Turabah area is located in the southwestern Arabian Shield of Saudi Arabia. The present study aims to shed light on the origin and mechanism of formation of the ironstones of the Tertiary sedimentary succession of the Umm Himar Formation in Turabah area. These ironstones are enclosed within mudstones and carbonates with less frequent sandstone. These lithologies show lateral and vertical facies changes and thickness variations and are stacked in cyclic nature within seven sedimentary units. The studied ironstones are present in two main horizons within the lower part of the succession as follows. (1) Lower massive and oolitic hematitic ironstones which are present as thin continuous and discontinuous bands and laminae within the varicolored tuffaceous mudstone unit of the lower part of the succession. The oolitic ironstones are present in successive small cycles. The lower parts of these cycles are composed of ferruginous friable mudstones. The middle parts are composed of hard ferruginous mudstones with abundant vertical and inclined burrows. The upper parts of these cycles are composed of indurated oolitic hematitic ironstones. The iron ooids of these ironstones were formed during successive and subsequent stages of diagenetic ferruginization of the precursor tuffaceous materials. (2) Upper bedded peloidal hematitic-magnetitic ironstones which are present in the hematitic-magnetitic ironstone unit no. 6 just overlying the bedded basalt unit no. 5. These ironstones were formed during subsequent stages of diagenetic ferruginization of precursor tuffaceous materials. These stages include the formation of green clays, devitrification, and finally ferruginization of the tuffaceous materials. This ironstone type is laterally changed into the penecontemporaneous bedded tuffaceous basalt.