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Much as using an internet browser bookmark will take you to a completely new page, using IGB bookmarks will clear away data from different species and/or genome versions and replace it with the data contained within the bookmark. The one time that IGB does this differently is if the data sets that are open match the same species and genome version in the bookmark; in this case, IGB will just add data sets or sources not already opened and zoom to the marked location. e.g. For instance, if you have open the 'TAIR9 ALL' data set from Arabidopsis thaliana, genome version June 2009 is selected, and the TAIR9 ALL data set is open. Your and your bookmark was made for the 'TAIR9 mRNA' data set , from the matching species and genome version. When , when the TAIR9 mRNA bookmark is activated, it will add the TAIR9 mRNA data set, zoom in to the location and then display both the TAIR9 ALL and the TAIR9 mRNA tracks.
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