Isthmus
Anisthmus(/ˈɪsməs,ˈɪsθməs/;[1]pl.:isthmusesoristhmi)[2]is anarrow piece of land connecting two larger areasacross an expanse of water by which they are otherwise separated.[3]Atombolois an isthmus that consists of aspitorbar,and astraitis the sea counterpart of an isthmus, a narrow stretch of sea between two landmasses that connects two larger bodies of water.
Isthmus vs land bridge vs peninsula[edit]
Isthmusandland bridgeare related terms, with isthmus having a broader meaning. Aland bridgeis an isthmus connecting Earth's major land masses. The termland bridgeis usually used inbiogeologyto describe land connections that used to exist between continents at various times and were important for the migration of people and various species of animals and plants, e.g.BeringiaandDoggerland.[4]
An isthmus is a land connection between two bigger landmasses, while apeninsulais rather a land protrusion that is connected to a bigger landmass on one side only and surrounded by water on all other sides. Technically, an isthmus can havecanalsrunning from coast to coast (e.g. thePanama Canal), and thus resemble two peninsulas; however, canals are artificial features distinguished fromstraits.
Major isthmuses[edit]
The world's major isthmuses include:
- Isthmus of Panamain theMiddle America
- Isthmus of Tehuantepecin theMiddle America
- Kra IsthmusonMainland Southeast Asia
- Isthmus of SuezbetweenNorth AfricaandWestern Asia
- Karelian IsthmusinEurope
Of historic importance were:
The cities ofAuckland,Manila,andSeattleare located on isthmuses.
Canals[edit]
Canals are often built across isthmuses, where they may be a particularly advantageous shortcut for marine transport. For example:
- The Panama Canal crosses theIsthmus of Panama,connecting theAtlanticandPacific Oceans
- TheSuez Canalconnects theMediterranean Seaand theRed Sea,cutting across the western side of the Isthmus of Suez, formed by theSinai Peninsula
- TheCrinan Canalcrosses the isthmus betweenLoch CrinanandLoch Gilp,which connects theKintyrepeninsula with the rest of Scotland
- TheWelland Canalin theNiagara Peninsula(technically an isthmus); it connectsLake OntariotoLake Erie
See also[edit]
- Land bridge– Connection between two land form bodies
- List of isthmuses
- List of straits
Notes[edit]
- ^"isthmus".CollinsDictionary.com.HarperCollins.Retrieved2016-12-19.
- ^fromAncient Greekἰσθμός(isthmós)'neck'LSJentryισθμός
- ^"Isthmus".Britannica.RetrievedSeptember 22,2013.
- ^"Land bridge | isthmus".Encyclopedia Britannica.
