Barriers between Zoogeographical regions:

Barriers between different regions:



Palearctic: Europe, North Africa (to Sahara), Asia (except India, Pakistan and SE Asia) and Middle East

Nearctic: Canada, USA, Mexico to tropics

Neotropical :Tropical Mexico south to South America, plus the Antilles

Afrotropic or Ethiopian :Madagascar, Africa south of the Sahara, southern Arabian Peninsula

Indo-Malayan or Oriental :Pakistan, India, Southeast Asia, Philippines, Indonesia west of Wallace's line (Sumatra, Java, Borneo)

Australian :Australia, New Guinea, Tasmania, Indonesian Islands east of Wallace's line (Celebes, Timor, etc.)

1. Barrier between Nearctic and Palearctic region

Both the regions are isolated by the oceans which are known as North Atlantic ocean and Arctic ocean: The Atlantic Ocean is the second largest of the world's oceanic divisions, following the Pacific Ocean. With a total area of about 106,400,000 square kilometres (41,100,000 sq mi), it covers approximately 20 percent of the Earth's surface and about 29 percent of its water surface area.
Arctic ocean almost completely surrounded by Eurasia and North America, the Arctic Ocean is partly covered by sea ice throughout the year (and almost completely inwinter). The Arctic Ocean's surface temperature and salinity vary seasonally as the ice cover melts and freezes.

2. Barrier between Neotropical and Nearctic regions.

To the south, in nearctic more habitable zone, it is a continent 5,000 kilometres (3,000 m) broad, but this narrows rapidly to an isthmus connecting it to the Neotropical realm in the south. Much of this isthmus is desert, and provides the barrier between this realm and its Neotropical neighbor. the isthmus between the Nearctic and Neotropical continents is a very temporary affair, breaking and re-uniting many times in the past, and each time having an effect on the migration of animals. At the moment the connection is complete, but that may not be for long.
Made by Muhammad Waseem, 931

3. Barrier between Neotropical and Ethiopian region.

Atlantic ocean ac as a barrier between Neotropical and Ethiopian region. Atlantic of this region is known as southern Atlantic or south Atlantic ocean. Soth atlantic isolate the Namibia, angola and gabon of Ethiopian rregion from neotropical region.
Also there are high mountains in Ethiopian near the south atlantic , so high even birds can’t cross this mountains. If a bird want to cross the south atlantic ocean it takes 3 days of flying.

4. Barrier between Ethiopian and Palearctic region

Sahara the great desert is the barrier between Ethiopian and Palearctic region. This desert is the world's largest hot desert, covering about a third of the African continent. It is the best known desert because it is so close to Europe. The Sahara covers most of North Africa and creates a formidable barrier between the Arab-Berber peoples of North Africa and the Black African peoples to the south.
The Sahel
The Sahara's southern edge expanded into the Sahel, a dry band that separates the desert from the southern, but some reports suggest that some of these areas are green and well-watered again.

5. Barrier between Ethiopian ,Oriental region and Australian region.

The Indian Ocean stretches between the east coast of Africa and the west coast of India.
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded by Asia on the north, on the west by Africa, on the east by Australia, and on the south by the Southern Ocean or, depending on definition, by Antarctica. Small Islands are present in the Ocean.

6. Barrier between Australian and Oriental region.

There are different small seas and land bridges and small Islands between them. For example The Arafura Sea lies west of the Pacific Ocean overlying the continental shelf between Australia and Indonesian New Guinea.
Behind this the areas which are acting as barrier also have some animals that can live in such condition, such as marine creatures and animals of frozen ice caps and hottest desert. They live in such conditions only and all other world act as barrier to them.

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