For more information, log on to- http://shomusbiology.weebly.com/ Download the study materials here- http://shomusbiology.weebly.com/bio-materials.html Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation. Habitat fragmentation can be caused by geological processes that slowly alter the layout of the physical environment[1] (suspected of being one of the major causes of speciation[1]), or by human activity such as land conversion, which can alter the environment much faster and causes extinctions of many species. The term habitat fragmentation includes five discrete phenomena: Reduction in the total area of the habitat Decrease of the interior : edge ratio Isolation of one habitat fragment from other areas of habitat Breaking up of one patch of habitat into several smaller patches Decrease in the average size of each patch of habitat Evidence of habitat destruction through natural processes such as volcanism, fire, and climate change is found in the fossil record.[1] For example, habitat fragmentation of tropical rainforests in Euramerica 300 million years ago led to a great loss of amphibian diversity, but simultaneously the drier climate spurred on a burst of diversity among reptiles. Habitat fragmentation is frequently caused by humans when native vegetation is cleared for human activities such as agriculture, rural development, urbanization and the creation of hydroelectric reservoirs. Habitats which were once continuous become divided into separate fragments. After intensive clearing, the separate fragments tend to be very small islands isolated from each other by cropland, pasture, pavement, or even barren land. The latter is often the result of slash and burn farming in tropical forests. In the wheat belt of central western New South Wales, Australia, 90% of the native vegetation has been cleared and over 99% of the tall grass prairie of North America has been cleared, resulting in extreme habitat fragmentation.

• published: 13 Nov 2013
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