No idea either what GAP meant, but the free dictionary acronyms has some possibilities

Great American Products
Generally Accepted Practices .. maybe not.
Global Atmospheric Pollution
Grant Awards Program
Gay and Proud .. don't think it's that
Group for Alternative Policies ... perhaps
General Area Plot.

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But the most odd one seemed to be their claim GAP is an acronym for 'Integrated Taxonomic Information System.' Don't see it, myself.