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