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  • Trinity Site, New Mexico Featured Article Trinity Site, New Mexico Trinity Site, New Mexico

    Trinity Site, Alamogordo Bombing Range, New Mexico ( 33°40'30.00"N, 106°28'30.00"W) was the site of the first atmospheric atomic bomb test which took... More »

  • Carpenter bee Featured Article Carpenter bee Carpenter bee

    This hexapod (six-legged) insect is a bee in the subfamily Xylocoinae of either the genus Ceratina or Xylocopa that makes its nest in wood or plant stems. Along... More »

  • Egypt Featured Article Egypt Egypt

    Egypt is a nation of eighty-four million people in north-Africa, it also controls the Sinai Peninsula, part of the Middle East and western-Asia. Thus, Egypt controls the only... More »

  • Limestone Featured Article Limestone Limestone

      Limestone  is a sedimentary rock whose chief mineral component is calcite (calcium carbonate: CaCO3). Limestone can be formed by precipitation of calcite... More »

  • Biological diversity in the Himalayas Featured Article Biological diversity in the Himalayas Biological diversity in the Himalayas

    Stretching in an arc over 3,000 kilometers of northern Pakistan, Nepal, Bhutan and the northwestern and northeastern states of India, the Himalaya hotspot includes all of... More »

  • Dugong Featured Article Dugong Dugong

    The Dugong, often referred to as the sea cow, is actually more closely related to elephants than to the bovine namesake.  Throughout much of their range, the Dugong has... More »

  • Marine microbes Featured Article Marine microbes Marine microbes

    The term 'Marine microbes' encompasses all microscopic organisms generally found in saltwater. Most micro-organisms are acellular and fall into the major categories of... More »

  • DNA Featured Article DNA DNA

    Deoxyribonucleic acid (DNA) is a long chain organic molecule that contains the coding for all metabolic and reproductive processes of all living organisms, save for certain... More »

Recently Updated
Spratly Islands Last Updated on 2015-05-29 13:36:55 The Spratly Islands consist of more than 100 small islands or reefs scattered over an area of nearly 410,000 sq km in the South China Sea, about two-thirds of the way from southern Vietnam to the southern Philippines. The closest countries to the Spratly Islands are Malaysia, Vietnam, Brunei and the Philipines. They are surrounded by rich fishing grounds and potential gas and oil deposits. (See Energy profile of South China Sea) These islands are strategically located near several primary strategic shipping lanes in the central South China Sea. There are no indigenous inhabitants. But there are scattered garrisons occupied by military personnel of several claimant states. They are claimed in their entirety by Taiwan, Vietnam and China, while portions are claimed by Malaysia and the Philippines. About 45 islands are occupied by relatively small numbers... More »
Zambezian flooded grasslands Last Updated on 2015-04-08 23:59:46 WWF Terrestrial Ecoregions Collection Located within the miombo and mopane woodlands of the Central African Plateau, Zambezian flooded grasslands are an anomaly of productivity and abundance in a landscape characterized by nutrient deficient soil and associated vegetation. Unlike the surrounding woodlands that generally support animals only in rather low densities, the wetlands and floodplains of this ecoregion provide habitats to sizable faunal populations, since food and water are abundant throughout most of the year. Large populations of waterbirds gather during the rainy season, and numerous herd animals and  carnivores  frequent the landscape. However, in a climate of rapid population growth and increasing need for land and natural resources, this fragile ecoregion may face increasing threat. Several conservation measures are... More »
Angolan scarp savanna and woodlands Last Updated on 2015-04-08 23:53:01 WWF Terrestrial Ecoregions Collection The Angolan scarp savanna and woodlands ecoregion is a complex area where several major African ecological zones meet, and where topographical features have resulted in a high diversity of vegetation types and significant levels of endemism. Biologically, the most important portion of the ecoregion is the west-facing scarp that supports rainforest at higher altitudes. This forest holds a significant number of endemic birds, and some other endemic animals and plants. The long period of insurrection, foreign mercenary activity and civil instability in Angola have contributed to the outcome that these forests and other parts of the ecoregion have never been adequately surveyed biologically, and hence more endemics can be expected with further study. However, the highly unstable civil war means that all biological... More »
Cactus Last Updated on 2015-04-08 23:49:44 Cactus is a family of plants that are specially adapted to survive arid conditions, most often having leaves reduced to spines, and succulent characteristics. The scientific family name Cactaceae is applied to this group comprising 121 different genera. This plant family is concentrated in the Americas and has a surprisingly broad latitude range in both the Northern and Southern Hemispheres. A considerable number of cacti species are threatened, chiefly due to habitat loss to agriculture, trampling by illegal human immigration into the southwestern USA, large-scale desert solar power projects, as well as overcollecting. The cactus family is generally considered native to the Americas. A notable exception is Mistletoe cactus, Rhipsalis baccifera, which is thought to have spread, fairly recently, from the American tropics to the subtropics and the deserts of the... More »
Cactaceae: The cactus family Last Updated on 2015-03-06 11:23:17 The Cactaceae is a family belonging to the order Caryophyllales.  Cacti typically are found in  dry and arid desert or semi-desert regions  with high average daytime temperatures and cold nights, and high evaporation rates.  Cacti range from Canada to Argentina, predominantly occurring in the warm and arid reaches of the continents of both North and South America across a wide range of different habitats like deserts, sandy coastal stretches, scrublands, dry deciduous forests, high alpine steppes and tropical rain forests (Barthlott and Hunt, 1993; Gibson and Nobel, 1986; Nyffeler, 2001). The main diversity centers are Mexico and south-west USA, central Andes, Brazil, Paraguay, Uruguay and Argentina with Mexico being the richest and most endemic region (Boyle and Anderson, 2002; Ortega-Baes and Godínez-Alvarez, 2006). The family is... More »