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Copper as a Factor in the Onset of Ascidian Metamorphosis


PRECOCIOUS metamorphosis of certain species of ascidian larvæ can be initiated by increasing the copper content of sea-water1,2. Furthermore, Glaser and Anslow3 observed that various materials that cause an acceleration of the onset of ascidian metamorphosis have an unusually high copper content; they concluded that the copper content of sea-water is causally related to the onset of natural metamorphosis. While this theory has not been generally accepted4, it has never been experimentally disproved.

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WHITTAKER, J. Copper as a Factor in the Onset of Ascidian Metamorphosis. Nature 202, 1024–1025 (1964).

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