The climates of the four main islands and thousands of smaller islands that make up Japan are amazingly diverse - they range from sub-tropical in the south to boreal in the north, with just about everything in between. About three quarters of the islands are covered in mountains, many of which are volcanic and more than a few active. This true-color Terra MODIS image from March 21, 2005, shows a significant portion of Honshu, the main island, as well as all of Shikoku and most of Kyushu.
Japan is one of the most densely populated areas as well, with more than 336 people per square kilometer. Human influence extends virtually all across the islands, meaning that native wildlife are extremely pressured. Some of Japan's more famous natives are the Japanese "Snow Monkeys" (also known as macaques), which are most northerly-living non-human primates in the world. 21 mammals native to Japan are threatened, along with 19 amphibian, 10 bird, and 1,950 plant species. Eighty percent of Japan's original vegetation has been lost.