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
Highveld grasslands Last Updated on 2015-07-04 17:44:26 WWF Terrestrial Ecoregions Collection Highveld grasslands ecoregion covers a large portion of west-central South Africa. Grasslands all over the world have experienced dramatic habitat destruction as a result of anthropogenic changes. The Highveld grasslands are no exception, with agriculture severely fragmenting this once-expansive region. This ecoregion now provides the last remaining stronghold of a number of grassland species that have suffered major reductions in abundance in the grassland biome, and which are consequently threatened with extinction (e.g. the Blue Crane (Anthropoides paradisea). There is a relatively biodiverse vertebrate fauna, with 608 taxa recorded. This ecoregion is part of the Montane Grasslands and Shrublands biome, within the Afrotropics Realm. The ecoregion draws its name from the high interior plateau known as... More »
Habitat fragmentation Last Updated on 2015-07-04 14:10:43 Habitat fragmentation involves alteration of habitat resulting in spatial separation of habitat units from a previous state of greater continuity. Figure 1. Aerial photograph of dry forest scrub in southern Zambia, fragmented by agricultural land conversion. 2008. Source: C.Michael Hogan This phenomenon occurs naturally on a geologic time-scale or in unusual and catastrophic events: however, since the Holocene era, humans have produced dramatic and swift transformation of landscapes throughout the world, resulting in a level of habitat fragmentation that has induced worldwide reduction in biodiversity and interuption of  sustainable yields of natural resources. Humans produce habitat fragmentation chiefly from agricultural land conversion, urbanization, pollution, deforestation and introduction of alien species; ironically, both human caused... More »
Madagascar spiny thickets Last Updated on 2015-06-25 20:16:56 WWF Terrestrial Ecoregions Collection The Madagascar spiny thickets or spiny desert of southern Madagascar, also referred to as deciduous thicket, is a globally distinctive ecoregion. This ecoregion is part of the Deserts and Xeric Shrublands biome, within the Afrotropics Realm. While the island of Madagascar is notable for exceptional levels of endemic plants and animals, the spiny thicket is particularly distinctive with 95 percent of the plant species endemic to the ecoregion. Members of the endemic Didiereaceae family present dominate the thicket, which have similar xeric adaptations to New World cacti, such as small leaves and spines, but with the Madagascar spiny thickets displaying more woody rather than succulent characteristics. There are a total of 288 recorded vertebrate taxa in the Madagascar spiny thickets, including several endemic... More »
Madagascar dry deciduous forests Last Updated on 2015-06-02 11:51:21 WWF Terrestrial Ecoregions Collection The Madagascar dry deciduous forests of western Madagascar are some of the world’s most species rich and most distinctive tropical dry forests. They are characterized by very high local plant and animal endemism at the species, genera and family levels. A significant fraction of these dry forests have been previously cleared, and the remaining forests are fragmented and critically threatened by uncontrolled burning and cuttining for charcoal production, grazing and agriculture. Since human settlement of this region during the Holocene, an estimated 97 percent of the island’s dry deciduous western forests have been destroyed, and those remaining are extremely localized and fragmented. This ecoregion also contains spectacular limestone karst formations, known as tsingy, and their associated forests,... More »
Zambezian flooded grasslands Last Updated on 2015-06-01 15:56:03 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 the majority 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... More »