Even tiger biologists cannot always say for certain to which subspecies a particular tiger belongs simply by looking at its appearance. The main differences are in size , color , and coat . Size Tigers found in the cool climates of northern regions are larger than tigers which live in equatorial climates. For example, a male Siberian tiger can weigh as much as 300 kilograms, compared to a male Sumatran tiger, which may weigh only 100 kilograms. Northern tigers live in a colder climate and need a larger body to stay warm Tropical tigers eat less because of the heat, so they don't get as big Color Tigers differ by subspecies in both the intensity of their colored stripes, and the stripes themselves.
Scientists believe that tiger coloration and stripes evolved as a form of camouflage.
Tigers which live in dense tropical forests have darker and denser stripe patterns than tigers living in grasslands. In the same way, tigers which live in grasslands have darker and denser stripe patterns than tigers living in northern forests. All tigers have fur coats, but the length of the fur varies by subspecies. The males of some tiger subspecies also have thick white ruff of hair around their necks. Look at the two tigers below.