Explore the vast range of titles available.

PREMISE OF THE STUDY: Spermacoceae are mainly an herbaceous group in the Rubiaceae. However, a few lineages are woody and are found in a diverse range of habitat types. Three of the largest woody lineages (Arcytophyllum, Hedyotis, and Kadua) are characterized by their distribution in the moist tropical mountains and have disjunct distribution patterns with respect to their closest relatives. In this study, we explore the cases of derived woodiness in these three lineages and their diversification dynamics in the tropical mountains of Asia, the Pacific, and the Americas. METHODS: By combining phylogenetic results with wood anatomical studies, we estimated timing of origin of the three woody groups, inferred their ancestral traits and ancestral distribution ranges, analyzed their associations with the tropical upland habitat, and elucidated their diversification across tropical mountains. KEY RESULTS: The three woody clades originated and diversified from herbaceous ancestors in close association with the tropical upland habitat during the Miocene. The ancestral range for Asian‐Pacific Hedyotis is Africa/Madagascar and continental Asia for Pacific Kadua. The complex geological history of tropical Asia allowed Hedyotis to diversify faster and create narrow endemics near oceans in the highlands of the Western Ghats in India, Sri Lanka, Southeast Asia including southeastern China, and New Guinea. CONCLUSIONS: The three major woody clades in Spermacoceae have gained their woodiness independently from one another, subsequent to colonization by their ancestors from a different geographic environment. The evolution and diversification along the tropical mountain orogeny is strongly linked with the formation of woody habit and many narrow endemic species.

High-elevation ecosystems, such as those on Mount Kenya are undergoing significant changes, with accelerated glacial ice losses over the twentieth century creating new space for alpine plants to establish. These ecosystems respond rapidly to climatic variability and within decades of glacial retreat, Afroalpine pioneering taxa stabilize barren land and facilitate soil development, promoting complex patches of alpine vegetation. Periglacial lake sediment records can be used to examine centennial and millennial scale variations in alpine and montane vegetation compositions. Here we present a 5300-year composite pollen record from an alpine tarn (4370 m asl) in the Hausberg Valley of Mount Kenya. Overall, the record shows little apparent variation in the pollen assemblage through time with abundant montane forest taxa derived and transported from mid elevations, notably high abundances of aerophilous Podocarpus pollen. Afroalpine taxa included Alchemilla, Helichrysum and Dendrosenecio-type, reflecting local vegetation cover. Pollen from the ericaceous zone was present throughout the record and Poaceae percentages were high, similar to other high elevation pollen records from eastern Africa. The Oblong Tarn record pollen assemblage composition and abundances of Podocarpus and Poaceae since the late Holocene (~4000 cal yr BP-present) are similar to pollen records from mid-to-high elevation sites of nearby high mountains such as Mount Elgon and Kilimanjaro. These results suggest a significant amount of uphill pollen transport with only minor apparent variation in local taxa. Slight decreasing trends in alpine and ericaceous taxonomic groups show a long-term response to global late Holocene cooling and a step decrease in rate of change estimated from the pollen assemblages at 3100 cal yr BP in response to regional hydroclimatic variability. Changes in the principal component axis scores of the pollen assemblage were coherent with an independent mid-elevation temperature reconstruction, which supported the strong influence of uphill pollen transport from montane forest vegetation and association between temperatures and montane vegetation dynamics. Pollen accumulation rates showed some variability related to minerogenic sediment input to the lake. The Oblong Tarn pollen record provides an indication of long term vegetation change atop Mount Kenya showing some decreases in local alpine and ericaceous taxa from 5300-3100 cal yr BP and minor centennial-scale variability of montane taxa from mid elevation forests. The record highlights potentials, challenges and opportunities for the use of proglacial lacustrine sediment to examine vegetation change on prominent mountain massifs.

PREMISE OF THE STUDY: Qat (Catha edulis, Celastraceae) is a woody plant species cultivated for its stimulant alkaloids. Qat is important to the economy and culture in large regions of Ethiopia, Kenya, and Yemen. Despite the importance of this species, the wild origins and dispersal of cultivars have only been described in often contradictory historical documents. We examined the wild origins, human‐mediated dispersal, and genetic divergence of cultivated qat compared to wild qat. METHODS: We sampled 17 SSR markers and 1561 wild and cultivated individuals across the historical areas of qat cultivation. KEY RESULTS: On the basis of genetic structure inferred using Bayesian and nonparametric methods, two centers of origin in Kenya and one in Ethiopia were found for cultivated qat. The centers of origin in Ethiopia and northeast of Mt. Kenya are the primary sources of cultivated qat genotypes. Qat cultivated in Yemen is derived from Ethiopian genotypes rather than Yemeni wild populations. Cultivated qat with a wild Kenyan origin has not spread to Ethiopia or Yemen, whereas a small minority of qat cultivated in Kenya originated in Ethiopia. Hybrid genotypes with both Ethiopian and Kenyan parentage are present in northern Kenya. CONCLUSIONS: Ethiopian cultivars have diverged from their wild relatives, whereas Kenyan qat has diverged less. This pattern of divergence could be caused by the extinction of the wild‐source qat populations in Ethiopia due to deforestation, undersampling, and/or artificial selection for agronomically important traits.

Some eleven thousand years ago hunter–gatherers in the Near East initiated their transition to farming using an assemblage of eight founder crops: three cereals, four legumes and flax. The evidence show that each of these plant species was brought into domestication once or mostly twice, with no further redomestication. It seems that these species were carefully chosen by humans from the many hundreds of plants used. Apparently, these eight crops were those that best responded to the sowing–reaping agrotechnique, reflecting the biological factors that were later manifested in the success of these founder crops. While changing their own life style, the novel, successful farmers have gained extra food, prestige, property, power, and as a result more spouses and children, eventually leading to their higher biological fitness. This in turn led to the expansion of agriculture either by idea diffusion or by the dispersal of the farmers themselves with their original founder crops. Farming has dispersed to Europe, Asia and North Africa during the following millennia. Concurrently, other remote hunter–gatherer populations in additional worldwide centers, notably East Asia and the Americas have also moved to farming life, conceiving local plant species and the relevant agrotechniques. Regarding the life history of the various cultivated plant species and the capabilities of our ancestors it is suggested that the simplest explanation for the beginning of agriculture in the new worldwide centers is the idea diffusion to these remote areas.

Southern Asia is a vast and ecologically diverse region that extends from the deserts of Afghanistan to the rainforests of Thailand, and is home to a marvelously rich palm flora.Palms of Southern Asiais the only complete field guide to the 43 genera and 352 species of palms and rattans that occur in Afghanistan, Bangladesh, Bhutan, Cambodia, China, India, Japan, Laos, Myanmar, Nepal, Pakistan, Sri Lanka, Taiwan, Thailand, and Vietnam. This attractive guide's handsome illustrations and succinct, authoritative, and jargon-free text make identification easy. Each species account includes the correct scientific and common names, and fully describes morphology, habitat, and uses. Featuring a distribution map for most species and 256 full-color photographs, this is also the only field guide to cover the extremely diverse palm flora of Vietnam, and the first to offer a taxonomic overview of the rattan species of Southern Asia. Palms of Southern Asiais a book of major importance for botanists and an invaluable aid for naturalists and conservationists, and it's the perfect field guide for ecotourists traveling in the region. Covers all 352 naturally occurring palms in Southern AsiaFeatures full-color photographs of 256 species, many never before illustratedIncludes a distribution map for most speciesProvides the first taxonomic overview of the rattans of Southern Asia

The history of the classification of the genus Carex from 370 B.C.--1955 A.D., including a synopsis of the etymology of the generic name Carex, is reviewed. The refinement of descriptive terminology during the Middle Ages, caricology during the Renaissance period and the concepts of classification systems for Carex are also discussed.

Africa, the world’s second largest landmass, sits astride the equator. It spans a range of latitudes from 37°N near Tunis to 34.5°S at Cape Agulhas and is topographically more uniform than any other continent. Apart from restricted highland areas in the Atlas Mountains (highest peak 4165 m above sea level), the central Sahara (Tibesti Mountains, 3415 m), West Africa (Mount Cameroon, 4095 m), Ethiopia (Ras Dashan, 4543 m), East Africa (Mount Kilimanjaro, 5895 m), and the eastern escarpment of southern Africa (Thabana Ntlenyana, 3484 m), the vast majority of the continent lies below 2000 m. Because of the restricted extent