This tutorial has been optimized for Internet Explorer, 1024 X 768 resolution, and high color graphics.  Windows Media Player and/or RealPlayer should be set to their smallest form to allow viewing most of the screen while listening to recorded sounds.  In Media Player, this can be achieved by selecting the "miniplayer" skin set to "skin mode".  Key words in this tutorial are followed by microphone-shaped icons.  By clicking these icons, you will hear an American English pronunciation of the word or short phrase preceding it.  British English is often noticeably different in its pronunciation of species names and other scientific terms.