It has 20, 000 central nervous system cells so big they can be seen without a microscope. (Humans have 100 billion brain cells.) Kandel turned down an offer to run the psychiatry department at Harvard's Beth Israel Hospital and bet his career on the slugs.

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In addition to using the living system as artwork, Brown made a series of images with a scanning electron microscope, and using the techniques to create illuminated manuscripts, he applied gold leaf to the regions of the prints where the bacterial gold deposits were found.

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