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- Studying mammals: Return to the water
Studying mammals: Return to the water

Some of the most unusual and versatile of all the mammals are the groups that live, feed and reproduce underwater. In this free course, Studying mammals: Return to the water, we will see how these formerly land-based mammals adapted to a return to the water, discussing such challenges as breathing, movement and communication. This is the seventh course in the Studying mammals series.
NOTE: The Studying mammals series is gradually being updated and replaced. You can study an improved freestanding version of this course, titled Aquatic mammals, here:
https://www.open.edu/openlearn/nature-environment/aquatic-mammals/content-section-0
Course learning outcomes
After studying this course, you should be able to:
- contrast the physical properties of air and water and describe implications of such differences for aquatic mammals
- give examples of the adaptations displayed by aquatic mammals that enable them to hold their breath while submerged for relatively long periods
- describe some of the biological differences between pinnipeds, sirenians and cetaceans
- discuss the importance of communication by sound in aquatic mammals, describe the role of blubber and explain countercurrent heat exchange
- explain the diving response and its significance in natural dives.
First Published: 09/08/2012
Updated: 15/05/2019
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10 hours study
Level 1: Introductory
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