They are the world's longest snakes and longest reptile, but are not the most heavily built. Like all pythons, they are nonvenomous constrictors and normally not considered dangerous to humans. It is an excellent swimmer. The color pattern is a complex geometric pattern that incorporates different colors. The back typically has a series of irregular diamond shapes flanked by smaller markings with light centers. In this species' wide geographic range, much variation of size, color, and markings commonly occurs.