Acknowledgements

Except for third party materials and otherwise stated (see terms and conditions [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] ), this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence.

Course image: Ken Schneider in Flickr made available under Creative Commons Attribution-NonCommercial-ShareAlike 2.0 Licence.

Grateful acknowledgement is made to the following sources for permission to reproduce material in this course:

Reading 1: Phillips, H. (2001) Into the abyss, New Scientist, 31 March 2001, The New Scientist;

Reading 2: Reprinted with permission from Davis, R. W. (1999) Science, vol. 283, copyright © 1999 American Association for the Advancement of Science.

Figure 1 & 3 Bonner, W. N. (1980) Whales, Blandford Press Ltd;

Figure 2a Adapted from Bonner, W. N. (1980) Whales, Blandford Press Ltd;

Figure 4 Reprinted with permission from Davis, R. W. (1999) Science, vol. 283, copyright © 1999 American Association for the Advancement of Science.

Don't miss out:

If reading this text has inspired you to learn more, you may be interested in joining the millions of people who discover our free learning resources and qualifications by visiting The Open University - www.open.edu/ openlearn/ free-courses