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  • 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 »

  • Healthy Community Design Featured Article Healthy Community Design Healthy Community Design

    The way we design and build our communities can affect our physical and mental health. Healthy community design integrates evidence-based health strategies into community... 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 »

  • 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 »

  • 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 »

  • 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 »

  • 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 »

  • Gymnosperm Featured Article Gymnosperm Gymnosperm

    A gymnosperm is one of a number of non-flowering seed bearing vegetation species, including conifers, cycads, Ginkgo and Gnetales.  These species arose first in the... 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 »

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 »
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 »
Mexico Last Updated on 2015-03-04 21:00:34 Mexico is a North American nation of one hundred and fifteen million people located between the United States to the north and the Central American nations of Guatemala and Belize to the south. Mexico's main environmental issues include: scarcity of hazardous waste disposal facilities; rural to urban migration; scarce and polluted fresh water resources in the northern parts of the country: inaccessible and poor water quality in central regions and extreme southeast regions; raw sewage and industrial effluents polluting rivers in urban areas; deforestation; widespread erosion; desertification; deteriorating agricultural lands; serious air and water pollution in the national capital and urban centers along US-Mexico border; and, land subsidence in Valley of Mexico caused by groundwater overdrafting. The Mexican government considers both the lack of clean water and... More »