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Dracaena Serrulata
''Dracaena serrulata'' also called the Arabian or Yemen Dragon Tree is a distinctive tree reaching around 5m tall with a single trunk. It is found in the dry escarpment mountains of southwestern Arabia from Oman, South Yemen and Saudi Arabia. Habitat ''Dracaena serrulata'' is restricted largely to the highest, dry plateaus at the back of monsoon mountains- an area which monsoon rains do not reach. ''Dracaena serrulata'' grows commonly in association with species as ''Vachellia etbaica'' and '' Grewia erythraea''. Uses The stiff leaves of the ''Dracaena serrulata'' were an important source of fibre and rope. The large, stiff and spike-tipped leaves were cut or pulled from the trunk, and beaten with heavy clubs to loosen and crack open the rigid outer casing of the leaf. Then the leaves were taken to water and left to soak in it for some weeks. Once thoroughly softened, the leaves were removed from the water and piled up in heaps on a hard flat surface, and then beaten and thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Gilbert Baker
John Gilbert Baker (13 January 1834 – 16 August 1920) was an English botanist. His son was the botanist Edmund Gilbert Baker (1864–1949). Biography Baker was born in Guisborough in North Yorkshire, the son of John and Mary (née Gilbert) Baker, and died in Kew. He was educated at Quaker schools at Ackworth School and Bootham School, York. He then worked at the library and herbarium of the Royal Botanic Gardens, Kew between 1866 and 1899, and was keeper of the herbarium from 1890 to 1899. He wrote handbooks on many plant groups, including Amaryllidaceae, Bromeliaceae, Iridaceae, Liliaceae, and ferns. His published works includ''Flora of Mauritius and the Seychelles''(1877) and ''Handbook of the Irideae'' (1892). He married Hannah Unthank in 1860. Their son Edmund was one of twins, and his twin brother died before 1887. John G. Baker was elected a Fellow of the Royal Society in 1878. He was awarded the Veitch Memorial Medal of the Royal Horticultural Society in 1907. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precipices
In geography and geology, a cliff is an area of rock which has a general angle defined by the vertical, or nearly vertical. Cliffs are formed by the processes of weathering and erosion, with the effect of gravity. Cliffs are common on coasts, in mountainous areas, escarpments and along rivers. Cliffs are usually composed of rock that is resistant to weathering and erosion. The sedimentary rocks that are most likely to form cliffs include sandstone, limestone, chalk, and dolomite. Igneous rocks such as granite and basalt also often form cliffs. An escarpment (or scarp) is a type of cliff formed by the movement of a geologic fault, a landslide, or sometimes by rock slides or falling rocks which change the differential erosion of the rock layers. Most cliffs have some form of scree slope at their base. In arid areas or under high cliffs, they are generally exposed jumbles of fallen rock. In areas of higher moisture, a soil slope may obscure the talus. Many cliffs also featu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Distribution
Species distribution —or species dispersion — is the manner in which a biological taxon is spatially arranged. The geographic limits of a particular taxon's distribution is its range, often represented as shaded areas on a map. Patterns of distribution change depending on the scale at which they are viewed, from the arrangement of individuals within a small family unit, to patterns within a population, or the distribution of the entire species as a whole (range). Species distribution is not to be confused with dispersal, which is the movement of individuals away from their region of origin or from a population center of high density. Range In biology, the range of a species is the geographical area within which that species can be found. Within that range, distribution is the general structure of the species population, while dispersion is the variation in its population density. Range is often described with the following qualities: * Sometimes a distinction is made betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fertility
Fertility is the capability to produce offspring through reproduction following the onset of sexual maturity. The fertility rate is the average number of children born by a female during her lifetime and is quantified demographically. Fertility is addressed when there is a difficulty or an inability to reproduce naturally, which is referred to as infertility. Infertility is widespread, with fertility specialists available all over the world to assist mothers and couples who experience difficulties having a baby. Human fertility depends on factors of nutrition, sexual behaviour, consanguinity, culture, instinct, endocrinology, timing, economics, personality, way of life, and emotions. Fertility differs from fecundity, which is defined as the ''potential'' for reproduction (influenced by gamete production, fertilization and carrying a pregnancy to term). Where a woman or the lack of fertility is infertility while a lack of fecundity would be called sterility. Demography I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Size
In population genetics and population ecology, population size (usually denoted ''N'') is the number of individual organisms in a population. Population size is directly associated with amount of genetic drift, and is the underlying cause of effects like population bottlenecks and the founder effect. Genetic drift is the major source of decrease of genetic diversity within populations which drives fixation and can potentially lead to speciation events. Genetic drift Of the five conditions required to maintain Hardy-Weinberg Equilibrium, infinite population size will always be violated; this means that some degree of genetic drift is always occurring. Smaller population size leads to increased genetic drift, it has been hypothesized that this gives these groups an evolutionary advantage for acquisition of genome complexity. An alternate hypothesis posits that while genetic drift plays a larger role in small populations developing complexity, selection is the mechanism by which la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endangered Species
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and invasive species. The International Union for Conservation of Nature (IUCN) Red List lists the global conservation status of many species, and various other agencies assess the status of species within particular areas. Many nations have laws that protect conservation-reliant species which, for example, forbid hunting, restrict land development, or create protected areas. Some endangered species are the target of extensive conservation efforts such as captive breeding and habitat restoration. Human activity is a significant cause in causing some species to become endangered. Conservation status The conservation status of a species indicates the likelihood that it will become extinct. Multiple factors are considered when assessing the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goats
The goat or domestic goat (''Capra hircus'') is a domesticated species of Caprinae, goat-antelope typically kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the animal family Bovidae and the tribe Caprini, meaning it is closely related to the sheep. There are over 300 distinct breeds of goat.Hirst, K. Kris"The History of the Domestication of Goats".''About.com''. Accessed August 18, 2008. It is one of the oldest domesticated species of animal, according to archaeological evidence that its earliest domestication occurred in Iran at 10,000 calibrated calendar years ago. Goats have been used for milk, Goat meat, meat, Animal fur, fur, and Animal skin, skins across much of the world. Milk from goats is often turned into goat cheese. Female goats are referred to as ''does'' or ''nannies'', Entire (animal), intact males are called ''bucks'' or ''billies'', and juvenile goats of both sexes are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leather
Leather is a strong, flexible and durable material obtained from the tanning, or chemical treatment, of animal skins and hides to prevent decay. The most common leathers come from cattle, sheep, goats, equine animals, buffalo, pigs and hogs, and aquatic animals such as seals and alligators. Leather can be used to make a variety of items, including clothing, footwear, handbags, furniture, tools and sports equipment, and lasts for decades. Leather making has been practiced for more than 7,000 years and the leading producers of leather today are China and India. Animal rights groups claim that modern commercial leather making and the consumption of its products is unethically killing animals. According to the life-cycle assessment (LCA) report for the United Nations Industrial Development Organization, 99% of the raw hides and skins used in the production of leather derive from animals raised for meat and/or dairy production. Critics of tanneries claim that they engage in uns ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drum
The drum is a member of the percussion group of musical instruments. In the Hornbostel-Sachs classification system, it is a membranophone. Drums consist of at least one membrane, called a drumhead or drum skin, that is stretched over a shell and struck, either directly with the player's hands, or with a percussion mallet, to produce sound. There is usually a resonant head on the underside of the drum. Other techniques have been used to cause drums to make sound, such as the thumb roll. Drums are the world's oldest and most ubiquitous musical instruments, and the basic design has remained virtually unchanged for thousands of years. Drums may be played individually, with the player using a single drum, and some drums such as the djembe are almost always played in this way. Others are normally played in a set of two or more, all played by the one player, such as bongo drums and timpani. A number of different drums together with cymbals form the basic modern drum kit. Uses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sling Shots
sling may refer to: Places * Sling, Anglesey, Wales *Sling, Gloucestershire, England, a small village in the Forest of Dean People with the name * Otto Šling (1912–1952), repressed Czech communist functionary Arts, entertainment, and media * Sling (Transformers), a fictional character * Sling TV, a U.S. IPTV service operated by Dish Network * Sling (album), 2021 studio album by Clairo Clothing * Baby sling, a piece of fabric tied to carry a child or infant * Sling swimsuit, a type of swimsuit, sometimes a bikini variant * Slingback, a type of woman's shoe Devices and weapons * Sling (cannon), an early modern gunpowder weapon * Sling (climbing equipment), a loop of webbing that can be wrapped around rock or tied to other equipment * Sling (firearms), a type of strap or harness that allows convenient carrying of a long gun and/or bracing of the weapon for better stability during aiming * Sling (furniture), a suspended, free-swinging chair, bed, or hammock ** Sex swing, als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
