Why is a Siberian tiger the biggest tiger?

The Siberian tiger, also known as the Amur tiger, is the largest tiger subspecies primarily due to its adaptation to the colder climate of its native habitat in the Russian Far East. Its larger size and heavier build help it conserve heat and provide greater strength for hunting larger prey, such as elk and wild boar. Additionally, genetic factors and the availability of resources in its environment contribute to its size, as larger individuals may have better survival and reproductive success.