Aïr Mountains
The Aïr Mountains is a triangular massif
In geology, a massif is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole...

, located in northern Niger
Niger , officially named the Republic of Niger, is a landlocked country in Western Africa, named after the Niger River. It borders Nigeria and Benin to the south, Burkina Faso and Mali to the west, Algeria and Libya to the north and Chad to the east...

, within the Sahara
The Sahara is the world's second largest desert, after Antarctica. At over , it covers most of Northern Africa, making it almost as large as Europe or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts, to the outskirts of the Atlantic Ocean...

A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...

. Part of the West Saharan montane xeric woodlands
West Saharan montane xeric woodlands
The West Saharan montane xeric woodlands is an ecoregion that extends across several highland regions in the Sahara. Surrounded at lower elevations by the largely barren Sahara, the West Saharan montane xeric woodlands are isolated refuges of plants and animals that can survive in the higher...

An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...

, they rise to more than 6,000 ft (1 830 m) and extend over 84 000 km². Lying in the midst of desert north of the 17th parallel
17th parallel north
The 17th parallel north is a circle of latitude that is 17 degrees north of the Earth's equatorial plane. It crosses Africa, Asia, the Indian Ocean, the Pacific Ocean, Central America, the Caribbean and the Atlantic Ocean....

, the Aïr plateau, with an average altitude between 500 and 900 m, forms an island of Sahel
The Sahel is the ecoclimatic and biogeographic zone of transition between the Sahara desert in the North and the Sudanian Savannas in the south.It stretches across the North African continent between the Atlantic Ocean and the Red Sea....

 climate which supports a wide variety of life, many pastoral and farming communities, and dramatic geological and archaeological sites. There are notable archaeological excavations in the region that illustrate the prehistoric past of this region. The endangered Painted Hunting Dog, Lycaon pictus once existed in this region, but may now be extirpated due to human population pressures
Overpopulation is a condition where an organism's numbers exceed the carrying capacity of its habitat. The term often refers to the relationship between the human population and its environment, the Earth...

 in this region.


The Precambrian
The Precambrian is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale...

 Aïr Mountains consist of peralkaline
Peralkaline rocks include those igneous rocks which have a deficiency of aluminium such that sodium and potassium are in excess of that needed for feldspar. The presence of aegerine and riebeckite are indicative of peralkaline conditions....

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

 intrusions which appear dark in colour (unusual since most granitic masses are light-toned in the field). In the Sahara Desert such mountains often stand out in stark relief as topographic heights amidst lowlands covered by sand. The terrain consists of high plateau, mountain ranges, and broad, sandy valleys and seasonal wadis which once contained rivers. Areas of these deep, often intersecting, valleys also contain waterborne clay and silt deposits. Underground watercourses in some of these valleys continue to provide year round oasis and seasonal vegetation.

The Aïr mountains themselves consist of nine almost circular massifs rising from a rocky plateau, bordered by the sand dunes and plain of the Ténéré Desert
The Ténéré is a desert region in the south central Sahara. It comprises a vast plain of sand stretching from northeastern Niger into western Chad, occupying an area of over...

 to the east.

The massif is a plateau
In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...

 consisting of a Cambrian
The Cambrian is the first geological period of the Paleozoic Era, lasting from Mya ; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latin name for Wales, where Britain's...

 age erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...

 surface on Precambrian metamorphic rock
Metamorphic rock
Metamorphic rock is the transformation of an existing rock type, the protolith, in a process called metamorphism, which means "change in form". The protolith is subjected to heat and pressure causing profound physical and/or chemical change...

s, punctuated by a series of flat-topped, granite intrusion peaks, which include Mont Idoukal-n-Taghès
Mont Idoukal-n-Taghès
Mont Idoukal-n-Taghès is the highest mountain in Niger. Mont Idoukal-n-Taghès is located in the south central Aïr Mountains, and is at the northern end of the Bagzane plateau. The village and pilgrimage site of Abatol sits at the base of the peak...

 (Niger's highest point at 2022 m), Mont Tamgak (1988 m), Mont Greboun (1944 m), Adrar Bous, Fadei, Chirriet, Taghmert, Agueraguer, Takaloukouzet, and Goundai.

The massif contains volcanic features including the extinct caldera
A caldera is a cauldron-like volcanic feature usually formed by the collapse of land following a volcanic eruption, such as the one at Yellowstone National Park in the US. They are sometimes confused with volcanic craters...

 of Arakao, Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...

 lava flows of hawaiite
Hawaiite is an olivine basalt with intermediate composition between alkali olivine and mugearite. It was first described at the island of Hawaii. In gemology, hawaiite is a colloquial term for Hawaii-originated peridot,which is gem-quality olivine mineral....

 to trachyte
Trachyte is an igneous volcanic rock with an aphanitic to porphyritic texture. The mineral assemblage consists of essential alkali feldspar; relatively minor plagioclase and quartz or a feldspathoid such as nepheline may also be present....

 composition, volcanic cone
Volcanic cone
Volcanic cones are among the simplest volcanic formations. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption...

s, tuff
Tuff is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered...

 rings and one of the largest ring dike system
Ring dike
A ring dike or ring dyke in geology refers to an intrusive igneous body. Their chemistry, petrology and field appearance precisely match those of dikes or sill, but their concentric or radial geometric distribution around a centre of volcanic activity indicates their subvolcanic origins.-Notable...

s in the world.

At Izouzaoenehe, lie the marble
Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite.Geologists use the term "marble" to refer to metamorphosed limestone; however stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for...

 Blue Mountains
Blue Mountains (Niger)
The Blue Mountains are a mountain range in Niger in the northeastern section of the Aïr Massif, about 100 km ENE of the town of Iférouane and 30 km NE of the Tezerik oasis...

, and the lower Zagado valley is surrounded by white marble hills.

The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

 and coal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...

 units in the Iullemmeden Basin
Iullemmeden Basin
The Iullemmeden Basin is a major sub-Saharan inland basin in West Africa, extending about 1000 km north to south and 800 km east to west...

 just to the west of the massif contain uranium
Uranium is a silvery-white metallic chemical element in the actinide series of the periodic table, with atomic number 92. It is assigned the chemical symbol U. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons...

 mineralisation sourced from the granites of the massif.


Because of its altitude (on average between 500 and 900 m) and despite its low rainfall (50 to 160 mm/year on the lower plateau), the Aïr forms a green region in comparison with the surrounding deserts, especially after the August-September seasonal rains. The climate is classified as Sahel
The Sahel is the ecoclimatic and biogeographic zone of transition between the Sahara desert in the North and the Sudanian Savannas in the south.It stretches across the North African continent between the Atlantic Ocean and the Red Sea....

, like that of the regions well to its south. While the mountains are largely bare of vegetation, the dry wadi
Wadi is the Arabic term traditionally referring to a valley. In some cases, it may refer to a dry riverbed that contains water only during times of heavy rain or simply an intermittent stream.-Variant names:...

 river valleys (known by the Hausa
Hausa language
Hausa is the Chadic language with the largest number of speakers, spoken as a first language by about 25 million people, and as a second language by about 18 million more, an approximate total of 43 million people...

 term "Kori") channel and hold rainwater in guelta
A guelta is a peculiar type of wetland, typical of desert regions. They are formed when underground water in lowland depressions spills to the surface and creates permanent pools and reservoirs....

s (stone pools, such as that near the town of Timia
Timia is a small town in northern Niger situated at an oasis in the Aïr Mountains, Agadez Region, Arlit Department. Visitors come to the Tuareg town to see a seasonal waterfall, a former French fort and the nearby ruined town of Assodé....

), creating oases which provide forage for animals, and in some areas, farming. The high Bagzane plateau of the central Aïr in particular provides adequate rainfall for intensive agriculture. Other, vast, areas of the region are entirely devoid of plant life and with their volcanic protrusions and rock fields
A hamada is a type of desert landscape consisting of largely barren, hard, rocky plateaus, with very little sand. A hamada may sometimes also be called a reg , though this more properly refers to a stony plain rather than a highland.Hamadas exist in contrast to ergs, which are large areas of...

 present an otherworldly appearance.


More than 430 vascular species has been recorded so far in the Aïr mountains . The location of the Aïr as a southern extension of the Hoggar mountain range makes it a connection between the Saharan Flora and the Sahelian Flora . However, the presence of mountains up to 2000 m a.s.l. generates locally favourable conditions for several species of the Sudanian zone and the Mediterranean zone .

During the 20th Century a series of scientific missions in the Aïr has permitted to identify the majority of plant species developing in the Aïr . Acacia tortilis subsp. raddiana
Acacia tortilis
Acacia tortilis, the Umbrella Thorn Acacia, also known as Umbrella Thorn and Israeli Babool, is a medium to large canopied tree native primarily to the savanna and Sahel of Africa , but also occurring in the Middle East....

 (Afagag) and Balanites aegyptiaca
Balanites aegyptiaca
Balanites aegyptiaca is a species of tree, classified either as a member of the Zygophyllaceae or the Balanitaceae. This tree is native to much of Africa and parts of the Middle East....

 (Aborak) are among the most frequent tree species in the intermountain zone. In the vicinity of temporary rivers named koris, species like Acacia nilotica
Acacia nilotica
Acacia nilotica is a species of Acacia native to Africa and the Indian subcontinent...

, Faidherbia albida
Faidherbia albida
Faidherbia albida is a species of Faidherbia native to Africa and the Middle East, formerly widely included in the genus Acacia. It has also been introduced to India and Pakistan. Common names for it include Apple-ring Acacia, Ana Tree and Winter Thorn.It is a thorny tree growing up to 6–30 m tall...

 and the palm Hyphaene thebaica coexist with planted date palms Phoenix dactylifera. Severe droughts and high aridity have made the intermountain zone of the Aïr a particularly harsh place for plants to develop . The additional presence of domestic herbivores has led to a severe deficit in tree regeneration, which has been cited as a major ecological concern . Tree regeneration has been observed enhanced as soon as tree seedlings are protected by large tussocks of the frequent grass Panicum turgidum
Panicum turgidum
Panicum turgidum is an old world clumping desert bunchgrass of the Panicum genus.-Distribution:It is common across the Sahara and Arabia, from Senegal to Pakistan, and known by the a number of common names, most widely as Taman, tuman, or thaman in Egypt and Arabia; merkba or markouba in...

 . This positive interaction between plants represents a promising restoration tool to be used by local inhabitants.

In comparison, mountainous areas are even less documented. Tropical tree species less resistant to drought have been described in the highlands, among which the Fabaceae Acacia laeta
Acacia laeta
Acacia laeta, commonly known as the Gay Acacia, is in the Acacia family.-Description:It is a perennial shrub or tree growing to a height of 4-10m...

 and Acacia seyal
Acacia seyal
Acacia seyal, the Red acacia, known also as the shittah tree , is a thorny, 6–10 m high tree with a pale greenish or reddish bark. At the base of the 3–10 cm feathery leaves there are two straight, light grey thorns, growing to 7–20 cm long...

 . Quezel has observed the remnant presence of a rare endemic taxa related to the Olive tree in the Northern sector of the Aïr range. Recently, this taxa, Olea europaea subsp. laperrinei, has been found in other mountains of the Aïr: these very isolated, small populations represent the Southern limit of the species distribution . A study led on the slopes of the highest summit in the Aïr, Idoukal’N’Taghes (2022 m a.s.l.), identified plant species that had never been inventoried in Niger before . Among them, Pachycymbium decaisneanum, Cleome aculeata, Echinops mildbraedii and Indigofera nummularia are tropical species with relatively low resistance to water stress, whereas Silene lynesii, Tephrosia elegans, and Echinops mildbraedii have a Saharan-Mediterranean distribution. Interestingly, three ferns were found for the first time in the Aïr recently, Cheilanthes coriacea, Actiniopteris radiata
Actiniopteris radiata
Actiniopteris radiata is a widely distributed fern occurring throughout Africa and adjacent islands, Madagascar, Arabia, Iran, Afghanistan, Nepal, India, Sri Lanka, Burma and Australia....

, and Ophioglossum polyphyllum, suggesting that ferns may be more prone to develop in arid environments than commonly proposed . All these data evidence a marked mountain climatic specificity in the Aïr, with a positive impact on species richness and species diversity. Because of their strong geographic isolation within a Saharan matrix, these species have a high conservation value .


The town of Agadez
-Sources:* Aboubacar Adamou. "Agadez et sa région. Contribution à l'étude du Sahel et du Sahara nigériens", Études nigériennes, n°44, , 358 p.* Julien Brachet. Migrations transsahariennes. Vers un désert cosmopolite et morcelé . Paris: Le Croquant, , 324 p. ISBN : 978-2-91496865-2.*. Saudi Aaramco...

 in the heart of the Tuareg country is the capital of Aïr. Much of the Tuareg population of Aïr until recently led a nomad
Nomadic people , commonly known as itinerants in modern-day contexts, are communities of people who move from one place to another, rather than settling permanently in one location. There are an estimated 30-40 million nomads in the world. Many cultures have traditionally been nomadic, but...

ic life, relying essentially on camel and goats from which they take milk, meat and skins used in the production of local handicrafts. Most sedentary populations were either dependents of higher caste Tuareg pastoralists or the Ikelan
The Ikelan are a caste within the Tuareg people who were at one time slaves or servile communities...

 ( Bouzou in Hausa / Bella in Songhai
Songhay languages
The Songhay, Songhai, or Songai languages are a group of closely related languages/dialects centered on the middle stretches of the Niger River in the west African states of Mali, Niger, Benin, Burkina Faso, and Nigeria. They have been widely used as a lingua franca in that region ever since the...

), former slaves and captives of the Tuareg from Hausa
Hausa people
The Hausa are one of the largest ethnic groups in West Africa. They are a Sahelian people chiefly located in northern Nigeria and southeastern Niger, but having significant numbers living in regions of Cameroon, Ghana, Cote d'Ivoire, Chad and Sudan...

 and other southern peoples. These peoples were settled in northern oases, to tend the date palm
Date Palm
The date palm is a palm in the genus Phoenix, cultivated for its edible sweet fruit. Although its place of origin is unknown because of long cultivation, it probably originated from lands around the Persian Gulf. It is a medium-sized plant, 15–25 m tall, growing singly or forming a clump with...

 plantations held by the noble clans.

Agriculture products from oases such as Timia
Timia is a small town in northern Niger situated at an oasis in the Aïr Mountains, Agadez Region, Arlit Department. Visitors come to the Tuareg town to see a seasonal waterfall, a former French fort and the nearby ruined town of Assodé....

, Aouderas
Aouderas is an oasis village in the Aïr Mountains of northeastern Niger, about 90km North-Northeast of the Regional capital of Agadez...

 and Tabelot

 are traditionally exchanged against clothes, or salt, brought by camel caravans (Azalai
The Azalai is a semi annual salt caravan route practiced by Tuareg traders in the Sahara desert, or the act of traveling with a caravan along that route.- History :...

) from the remote Tenere oases of Bilma
Bilma is an oasis town in north east Niger with a population of around 2,500 people. It lies protected from the desert dunes under the Kaouar Cliffs and is the largest town along the Kaouar escarpment...

 and Fachi
Fachi is an oasis surrounded by the Ténéré desert and the dunes of the Erg of Bilma in eastern Niger, placed on the western edge of the small Agram mountain outcropping. It has an estimated population of some 2000 people. A stopping point of the Agadez to Kaouar caravans of the Azalay, Fachi is 150...

 to the east.


The Aïr is known for its rock art
Rock art
Rock art is a term used in archaeology for any human-made markings made on natural stone. They can be divided into:*Petroglyphs - carvings into stone surfaces*Pictographs - rock and cave paintings...

, dating from 6000 BC to around AD 1000. During the Neolithic Subpluvial
Neolithic Subpluvial
The Neolithic Subpluvial — sometimes called the Holocene Wet Phase — was an extended period of wet and rainy conditions in the climate history of northern Africa...

 the region was a pastoral
The adjective pastoral refers to the lifestyle of pastoralists, such as shepherds herding livestock around open areas of land according to seasons and the changing availability of water and pasturage. It also refers to a genre in literature, art or music that depicts such shepherd life in an...

 area, as is illustrated by images of cattle and large mammals. During the 3rd millennium BC
3rd millennium BC
The 3rd millennium BC spans the Early to Middle Bronze Age.It represents a period of time in which imperialism, or the desire to conquer, grew to prominence, in the city states of the Middle East, but also throughout Eurasia, with Indo-European expansion to Anatolia, Europe and Central Asia. The...

, however, a process of desertification
Desertification is the degradation of land in drylands. Caused by a variety of factors, such as climate change and human activities, desertification is one of the most significant global environmental problems.-Definitions:...

 began and the Tuareg from further north migrated into the region. Later art indicated war
War is a state of organized, armed, and often prolonged conflict carried on between states, nations, or other parties typified by extreme aggression, social disruption, and usually high mortality. War should be understood as an actual, intentional and widespread armed conflict between political...

, depicting horse
The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

s and chariot
The chariot is a type of horse carriage used in both peace and war as the chief vehicle of many ancient peoples. Ox carts, proto-chariots, were built by the Proto-Indo-Europeans and also built in Mesopotamia as early as 3000 BC. The original horse chariot was a fast, light, open, two wheeled...

s. In particular, a five-meter-high carving of a giraffe
The giraffe is an African even-toed ungulate mammal, the tallest of all extant land-living animal species, and the largest ruminant...

 at Dabous discovered in 1999 is internationally famous. Cave art in the region is predominantly stone carving
Stone carving
Stone carving is an ancient activity where pieces of rough natural stone are shaped by the controlled removal of stone. Owing to the permanence of the material, evidence can be found that even the earliest societies indulged in some form of stone work....

, initially with sharp rock, and from around 1200 BC perhaps with metal.

When the Tuareg tribes were pushed south by Arab invaders in the eighth and ninth centuries, there were Gobir
Gobir was a city-state in what is now Nigeria. Founded by the Hausa in the eleventh century, Gobir was one of the seven original kingdoms of Hausaland, and continued under Hausa rule for nearly seven hundred years. Its capital was the city of Alkalawa...

wa Hausa
Hausa people
The Hausa are one of the largest ethnic groups in West Africa. They are a Sahelian people chiefly located in northern Nigeria and southeastern Niger, but having significant numbers living in regions of Cameroon, Ghana, Cote d'Ivoire, Chad and Sudan...

 in the southern Aïr. Successive Tuareg Tels have controlled the area since at least the twelfth century. Agadez, as well as In-Gall
In-Gall is a town in the Agadez Region, Tchirozerine Department of northeast Niger, with a year-round population of less than 500...

 to the east, were the farthest outposts of the Songhai Empire
Songhai Empire
The Songhai Empire, also known as the Songhay Empire, was a state located in western Africa. From the early 15th to the late 16th century, Songhai was one of the largest Islamic empires in history. This empire bore the same name as its leading ethnic group, the Songhai. Its capital was the city...

 in the early 15th century. In the sixteenth century the area fell under the newly created Tuareg Sultanate of Aïr, and remained so until the arrival of the French
French West Africa
French West Africa was a federation of eight French colonial territories in Africa: Mauritania, Senegal, French Sudan , French Guinea , Côte d'Ivoire , Upper Volta , Dahomey and Niger...

 at the end of the 19th.

The emergence of the French weakened the Tuareg Kels and provoked both infighting and resistance to colonialism. From the 1880s, Toubu raids increased, and when the Tuareg Ag Mohammed Wau Teguidda Kaocen
Ag Mohammed Wau Teguidda Kaocen
Ag Mohammed Wau Teguidda Kaocen was a Tuareg noble and clan leader. Born in 1880 near Zinder , Kaocen became the Amenokal of the southern Ikazkazan Tuareg, a subset of the Kel Owey confederation...

 rose against the French in 1917, many towns were destroyed on his way to the siege of Agadez. When the French retook Agadez, a brutal punitive expedition
Punitive expedition
A punitive expedition is a military journey undertaken to punish a state or any group of persons outside the borders of the punishing state. It is usually undertaken in response to perceived disobedient or morally wrong behavior, but may be also be a covered revenge...

 through the Aïr left many formerly populous places abandoned, razed by Kaosen and the French successively.

While the Kel Owey continued to dominate the settled oasis towns and pastoral herding, the sedentary farmers (Tuareg, Hausa, or Songhai) expanded farming and sedentary livestock cultivation in the mid 20th century.

The famines of the 1970s and 1980s brought an end to this expansion, and as Agadez
-Sources:* Aboubacar Adamou. "Agadez et sa région. Contribution à l'étude du Sahel et du Sahara nigériens", Études nigériennes, n°44, , 358 p.* Julien Brachet. Migrations transsahariennes. Vers un désert cosmopolite et morcelé . Paris: Le Croquant, , 324 p. ISBN : 978-2-91496865-2.*. Saudi Aaramco...

 and Arlit
Arlit is an industrial town and capital of the Arlit Department of the Agadez Region of northern-central Niger, built between the Sahara desert and the eastern edge of the Aïr mountains. It is 200 km south by road from the border with Algeria...

 grew, the towns of the Aïr have shrunk. The Tuareg Rebellion of the 1990s saw brutal government reprisals which depopulated many villages in the Aïr. Peace from the mid 1990s, as well as the uranium mines of Arlit
Arlit is an industrial town and capital of the Arlit Department of the Agadez Region of northern-central Niger, built between the Sahara desert and the eastern edge of the Aïr mountains. It is 200 km south by road from the border with Algeria...

 brought unprecedented growth to the region, with many small towns gaining valuable tourism revenue. In 2004, a locust invasion ravaged many gardens, bringing scarcity and contributing to the Second Tuareg Rebellion (beginning in 2007) which continues to plague the region, effectively ending the nascent tourist industry.

External links

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