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We assessed seven decades of change in the largest known population of the endangered endemic Boswellia elongata Balf. F. (Burseraceae) on Socotra Island (Yemen). To quantify the population change we evaluated tree number and locations on digitized images from various sources in the period 1956–2017 and combined this with direct field measurements of the population between 2011 and 2017. Our study reveals that the Homhil Nature Sanctuary B. elongata population shows a continuous decline since 1956. The steady but slow natural decline was strongly accelerated by two catastrophic cyclones in November 2015, when 38% of the trees were directly destroyed by strong winds. During the following 2 years 29% of the remaining trees died additionally. The remaining population has a bell-shaped size distribution; most trees are around 40 cm in diameter (range 18 to 70 cm). Tree ring analysis of 11 dead trees with a diameter of 29 to 44 cm without bark, resulted in estimated tree ages between 80 and 101 years. We estimate that similar-sized trees showing strong signs of senescence have a maximum age of a little over 100 years. The age structure of the Homhil population is, therefore, unbalanced with large sized trees prevailing. Natural regeneration is absent for decades. Viable seeds are available and have been shown to germinate, but the development of seedlings into saplings is a bottleneck. If the decline continues at the current rate, only 30 trees will remain there in 2036. Protection, planting and awareness activities are needed to keep this unique frankincense tree in Homhil Nature Sanctuary.

Recent fieldwork on the south coast of the island of Socotra, Yemen, has revealed a hitherto unknown petroglyph site. This site represents the first rock art to have been recorded on the south coast, an area generally regarded as being unpopulated up until the recent past. The corpus of recorded petroglyphs includes feet, cupules, anthropomorphic figures and geometric motifs, whose designs parallel those from known rock-art sites on the north coast. The importance of this site is that it provides us with the first glimpse into the religious and socio-political lives of the inhabitants of the previously unknown southern half of Socotra. Placing these petroglyphs within the broader context of rock-art studies on the island of Socotra has also allowed us to begin to disentangle the skewed view of Socotra's inhabitants.

This article is a broad review focused on dragon trees—one of the most famous groups of trees in the world, well known from ancient times. These tertiary relicts are severely endangered in most of the area where they grow. The characteristic features of the dragon tree group are described and the species belonging to this group are listed. This review gathers together current knowledge regarding the taxonomy, evolution, anatomy and morphology, physiology, and ontogeny of arborescent dragon tree species. Attention is also paid to the composition, harvesting, medicinal, and ethnobotanical use of the resin (dragons’ blood). An evaluation of population structure, distribution, ecology, threats, and nature conservation forms the final part of the review. In the conclusions we recommend further avenues of research that will be needed to effectively protect all dragon tree species.

Hawār? are traditionally logboats carved from a single tree into a double-ended vessel which can be propelled by either sails or paddle. Hawār? can be found throughout the Indian Ocean from India through to East Africa, yet little is known about this ubiquitous vessel. The aims of this research are to address this lacuna in our knowledge by documenting the rich source of hawār? present on the island of Socotra, Yemen. © 2009 The Author

The 2006 season has yielded significant new insights into the Great Wall of Gorgan's relation to landscape features and settlement, notably the division of the associated complex water supply system into sectors. The westernmost part of the wall is buried deeply beneath sediments from a past transgression of the Caspian Sea. An unexpectedly high number of brick kilns, of standardised design, shed light on the manner of the wall's construction. Geophysical survey, satellite images and excavations have established that some or all of the associated forts were densely occupied with buildings, thought to be barracks, suggesting a strong military garrison.