To see Demos on how to make this graphs, click on the links below:

Strategy: we are going to plot the body weights inside the graph we just finished doing. http://www.youtube.com/watch?v=JYm-OA-BknI Movie MP4(HD)
Plot the average body weight of males and females (learn also how to rename a series) http://www.youtube.com/watch?v=DyvOlIgNrB4 Movie MP4(HD)
Create a second Y axis and link the males and females body weight series to this second Y axis http://www.youtube.com/watch?v=SNzdKl97n_4 Movie MP4(HD)
Write and rotate the title of the secondary Y axis http://www.youtube.com/watch?v=tuabFrVg6iw Movie MP4(HD)
Re-scale the secondary Y axis http://www.youtube.com/watch?v=tvYb6iRtHO0 Movie MP4(HD)
Color code the data point and the line of the males and females body weight series http://www.youtube.com/watch?v=NJkrHW2eE74 Movie MP4(HD)
Plot their standard deviations as error bars and color code the error bars http://www.youtube.com/watch?v=gwGoYo-3wUQ Movie MP4(HD)
Modify the title of the graph http://www.youtube.com/watch?v=O0PzPru_2uI Movie MP4(HD)
Final touch http://www.youtube.com/watch?v=s_uwMsX5oHI Movie MP4(HD)