- Any geographical feature that prevents gene flow between populations.
Expanded glossary of Cycad terms . 2014.
Look at other dictionaries:
barrier — 01. The U.S. and Mexico are meeting today in an attempt to remove some [barriers] to trade between the two countries. 02. The police finally had to put up a [barrier] in the middle of the street in order to stop a teenager who had been speeding… … Grammatical examples in English
Geographical index of Toril — This article is about the fictional fantasy setting of Forgotten Realms. Places can be listed twice: once in political regions and once in geographical regions. Contents 1 Faerûn 1.1 Northwest Faerûn 1.2 North Faerûn … Wikipedia
Great Barrier Reef — geographical name coral reef 1250 miles (2012 kilometers) long Australia in Coral Sea off NE coast of Queensland; most of the area designated a marine park … New Collegiate Dictionary
Environmental threats to the Great Barrier Reef — The Great Barrier Reef is the world s largest coral reef system,cite web|author=UNEP World Conservation Monitoring Centre |year=1980|title=Protected Areas and World Heritage Great Barrier Reef World Heritage Area|url=http://sea.unep… … Wikipedia
Separation barrier — A separation barrier is a wall or fence constructed to limit the movement of people across a certain line or border, or to separate two populations. These structures vary in placement with regard to international borders and topography. The most… … Wikipedia
The Barrier — is a spectacular lava dam retaining the Garibaldi Lake system in southwestern British Columbia, Canada. It is over 300 m (1,000 ft) in thickness and about 2 km (1.2 mi) wide where it impounds the lake. [ [http://ilmbwww.gov.bc.ca/bcgn… … Wikipedia
Twin cities (geographical proximity) — Twin cities are a special case of two cities or urban centres which are born in close geographic proximity and then grow into each other over time. The term Twin Cities in the United States refers specifically to the cities Minneapolis and Saint… … Wikipedia
Bird migration — A flock of Barnacle Geese during autumn migration … Wikipedia
National Hockey League rivalries — Rivalries in the National Hockey League (NHL) have occurred between many teams and cities. Rivalries have arisen for many different reasons, the primary ones including geographic proximity, familiarity with opponents, on ice incidents (violence) … Wikipedia
Divided regions — are transnational regions, islands, etc., (i.e. areas that are known under a common name) that may have at one time been a united sovereign state but are or have been subsequently politically divided by national borders, into separate sovereign… … Wikipedia