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  • Endangered species Featured Article Endangered species Endangered species

    An endangered species is a biological taxon that is at risk of becoming extinct in a proximate time frame much sooner than the long term horizon in which species typically... 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 »

  • 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 »

  • 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 »

  • 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 »

  • Composting tips Featured Article Composting tips Composting tips

    Composting turns household wastes into valuable fertilizer and soil organic matter. All organic matter eventually decomposes. Composting speeds the process by providing an... More »

  • 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 »

  • 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 »

Recently Updated
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 »
Kalahari acacia-baikiaea woodlands Last Updated on 2015-04-08 23:56:27 WWF Terrestrial Ecoregions Collection Semi-arid Kalahari acacia-baikiaea woodland stretches across the center of southern Africa, from northern Namibia through Botswana and just into the Tuli Block of South Africa. Surface water is scarce here, and droughts occur approximately once every seven years. As a result, the human population is relatively low, especially on the sandveld that covers most of the ecoregion. This woodland supports a rich and diverse fauna, including a variety of ungulates and a number of threatened large mammals such as White Rhinoceros (Ceratotherium simum), Black Rhinoceros (Diceros bicornis), African Painted Hunting Dog (Lycaon pictus), and African Elephant (Loxodonta africana). However, human populations are increasing and the growing cattle industry has far-reaching adverse effects on the environment and wildlife. The... 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 »
Madagascar mangroves Last Updated on 2015-04-08 23:48:19 WWF Terrestrial Ecoregions Collection Shielded from monsoon winds by the central mountains of Madagascar, Madagascar mangroves occupy a wide range of environmental and climatic conditions along the western coastline along the Indian Ocean. Although the ecoregion’s species richness is low, it is unusual in supporting certain endemic tree species. The mangroves also shelter highly diverse mollusk and crustacean communities, while capturing sediment that threatens coral reefs and seagrass beds. Birds, sea turtles, and dugongs all utilize mangroves, as do the Malagasy people. Rice farming, shrimp aquaculture and construction materials are all carried out within these mangroves. On Madagascar, mangroves are found primarily along the western coast. They occur in a wide range of environmental and climatic conditions, fostered by a low coastal... More »