1.4 Moving to the water

In moving to the water, aquatic mammals have had to survive, feed and reproduce using a set of biological characteristics that evolved in association with life on land. This course will explore how these characteristics have provided challenges – as well as opportunities – for mammals that spend some or all of their time in the water. You will examine some of the important differences between a life in air and a life in water, and learn how the bodies and behaviour of aquatic mammals have become better suited to living and hunting in an aquatic environment. In Section 3, you will explore the so-called ‘diving response’, and some of the problems involved in finding out how the animals behave on their dives. Section 4 looks at what is now known about the evolution of the mammals that have made the most complete transition from the land to the water – the whales. And finally, Section 5 will examine how human activity impacts on these ecosystems.