Sure the Mon Calamari might not actually come from under the sea, but there's no way you can convince me that something that looks like that and has "Calamari" in its name doesn't smell like fish and if it made rum, I'm certain it would rub off.
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That is why in the Canon, they make better space combat tacticians, living underwater makes three dimensional movement is inherent and intuitive to them as a species. Whereas land dwelling humanoids are only inherently familiar with two dimensional thinking.
Yes, I am a geek and I fly my flag proudly.