Quite a few years ago, I spent some time viewing a natural history-inspired show at the Boston Museum of Fine Arts. One exhibit that especially caught my attention consisted of a meter-square dish containing what must have been EMB agar. This “plate” had been left exposed to the air and the ensuing mold colonies were allowed to grow until they became confluent. The result was stunning: individual molds displayed their natural colors plus those of the dyes (methylene blue and eosin) they selectively picked from the medium. The result was a riotous jumble of exceptionally vivid colors, from blues to reds.
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