Biogeography

Biogeography is the study of the distribution of biological organisms. The scale of analysis ranges from very small micro-topography regimes to continental dimensions. Fundamental concepts in this field of study are the nature of barrier formation and response of species to their patterns of travel and migration; in particular, the presence of rivers, mountain ranges, deserts and other natural boundaries are examples of large scale barriers. Besides such major landform barriers there are soil, topographic and meteorological factors that influence the distribution of each species. In the case of smaller scale regimes that are applicable for some bacteria or limited range plant species, there are often very restricted niches; for example, certain bacteria extremophiles may be limited to such localized features as small geyser pools, and some rare plants may have a single extant colony defined specialized soils such as serpentine and narrow climatic zone. Inherent in the concept of biogeography are the processes of speciation, extinction, dispersal and migration.   

  • Douglas-fir Featured Article Douglas-fir Douglas-fir

    The Douglas-fir (scientific name: Pseudotsuga) is a genus of tree that includes ar least five species found in North America and Asia: Scientific... More »

  • Ocean acidification troubles Featured Article Ocean acidification troubles Ocean acidification troubles

    The seas in which corals and other calcifying species dwell are turning acidic, their pH slowly dropping as Earth's oceans acidify in response to increased carbon dioxide... More »

  • Big Bend National Park, United States Featured Article Big Bend National Park, United States Big Bend National Park, United States

    Big Bend National Park is one of the two National Parks located in the state of Texas, in the USA. Big Bend National Park is located in the Big Bend region along the border of... More »

  • Great Victoria Desert Featured Article Great Victoria Desert Great Victoria Desert

    WWF Terrestrial Ecoregions Collection A vast, sparsely populated region covered by dunefields and gibber plains, the Great Victoria Desert... More »

  • Daugava River Featured Article Daugava River Daugava River

    The Daugava River drains portions of the countries of Latvia, Belarus and Russia, prior to discharging to the Gulf of Riga. Also known as the West Dvina River, this watercourse is... More »

  • Mojave Desert Featured Article Mojave Desert Mojave Desert

    WWF Terrestrial Ecoregions Collection The Mojave Desert is the smallest of the four North American deserts. While the Mojave lies between the... More »

  • Cactus Featured Article Cactus Cactus

    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... More »

  • Spinner dolphin Featured Article Spinner dolphin Spinner dolphin

    The Spinner dolphin (Stenella longirostris), a marine mammal in the family of oceanic dolphins,  gets its name from the spinning behavior it shows when it leaps out of... More »

  • Ecoregions of Chile Featured Article Ecoregions of Chile Ecoregions of Chile

    Chile has eight ecoregions that occur entirely or partly within its borders on the mainland and three ecorgions offshore: Sechura desert Atacama... 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 »
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 »
Sierra Nevada forests Last Updated on 2015-01-29 19:20:06 WWF Terrestrial Ecoregions Collection The Sierra Nevada forests are the forested areas of the Sierra Nevada Mountains, which run northwest to southwest and are approximately 650 kilometers long and 80 km wide. The range achieves its greatest height towards the south, with a number of peaks reaching heights of over 4000 meters. Several large river valleys dissect the western slope with dramatic canyons. The eastern escarpment is much steeper than the western slope, in general.   The range supports a diverse set of natural communities with many endemic species and extraordinary habitats. A significant fraction of the land area in the Sierra Nevada Mountains is unforested, since elevations above the treeline do not support even conifer growth. This ecoregion is part of the Nearctic Realm. The Sierra Nevada forests ecoregion harbors one of... More »