The lake in this photo looks as though it might be completely lacking in life. Even its name—the Dead Sea—adds to that impression. Located far below sea level, the Dead Sea is much saltier than the ocean. It’s too salty for fish, frogs, or other animals to survive. Yet even here, living things thrive. The bottom of the Dead Sea, for example, is carpeted with mats of microorganisms. How do they manage to live in these unusual conditions? How have they adapted to their extreme environment?
All organisms must adapt to their environment in order to survive. This is true whether they live in the highly salty water of the Dead Sea or in a lush tropical rainforest that is bursting with life. Most environments are not as extreme as the Dead Sea. But they all have conditions that require adaptations. In this chapter, you’ll read about a wide variety of environments and the organisms that live in them.