The tiger (Panthera tigris), a member of the Felidae family, is the largest of the four big cats in the genus Panthera. The tiger is native to much of eastern and southern Asia, and is an apex predator and an obligate carnivore. The larger tiger subspecies are comparable in size to the biggest extinct felids, reaching up to 3.3 metres (11 ft) in total length, weighing up to 300 kilograms (660 pounds), and having canines up to 4 inches (100 mm) long. Aside from their great bulk and power, their most recognisable feature is a pattern of dark vertical stripes that overlays near-white to reddish-orange fur, with lighter underparts. The most numerous tiger subspecies is the Bengal tiger, while the largest is the Siberian tiger. Tigers have a lifespan of 10 - 15 years in the wild, but can live longer than 20 years in captivity. They are highly adaptable and range from the Siberian taiga to open grasslands and tropical mangrove swamps. They are territorial and generally solitary animals, often requiring large contiguous areas of habitat that support their prey demands. This, coupled with the fact that they are indigenous to some of the more densely populated places on earth, has caused significant conflicts with humans. Three of the nine subspecies of modern tigers are extinct, and the remaining six are classified as endangered, some critically so. The primary direct causes are habitat destruction, fragmentation, and hunting.