So I enjoy surfing to see what else was written in those times. Today I spotted the seriously antique 'Seaweed Collector's Guide' of 1853. My eye was caught by the following piece of advice:
"I must now caution young beginners to keep apart from other plants all the different varieties of the genus Desmarestia, for they posess the peculiar property of changing the colour of, and very soon decomposing, all other plants, especially those of the finer species, with which they may come in contact.
"Notwithstanding what has been alleged to the contrary, most of the Desmarestiae, if kept out of sea-water, even for a very inconsiderable time, soon become flaccid, and rapidly advance towards decay."
He says that specimens must always be transported in seawater, as they get irreversibly ruined if you put them in fresh water. He sounds a bit peeved that he's made this observation and somebody is questioning whether it's his imagination or not (Notwithstanding...).
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| Desmarestia aculeata: public domain image from a Victorian seaweed herbarium in France. |
I couldn't help wondering what all this was about. It turns out to be rather interesting, as you can read on the Friday Harbor Laboratories' webpages. The Desmarestia stores sulphuric acid inside its vacuoles - resulting in an internal pH of 0.8 to 1.8 (really very low, like stomach or battery acid). So when the vacuoles burst, it's no wonder your specimens get ruined.
Researchers have shown that grazing sea-urchins are, unsurprisingly, put off from grazing Desmarestia and any other species that it's growing with. The acid erodes their 'teeth' and I imagine it wouldn't feel very nice elsewhere either. It seems that the sulphuric acid vacuoles have evolved as an anti-herbivore measure.
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