I recently received a message from Sean regarding the video of James Lendemer on the NPR website and some of the thoughts that it inspired in him:
I sent James's lichen video, by way of your blog, to a friend of mine, the botanist Lisa Kruse, and she, being sharper than me, noticed that the narrator says that the lichen fungus eats the algae. She then asked me if that is true because her understanding, and mine, was that the fungus appropriates from the algae, in one way or another, its nutrients without actually consuming the little green fellows. Instead of answering the question I sent her these three poems, or perhaps, poemules, would more accurately describe them. And thus I send them to you in the hope that you find them amusing.... on the other hand, if recent investigations have determined that the fungus does indeed devour the algae, I would like to know about that.
Three rhymes on the lichen symbiosis occasioned by a lichen video’s narrator having said that the lichen fungus eats the lichen algae.
Were I to venture to explain
How doth the fungus entertain,
I’d not have said he eats his guests
But rather shares in their bequests.
If to me the burden fell,
To illustrate the lichen, well,
More like the cow-maid, I would hold,
The fungus cultivates her fold,
She slaughters not her gentle beasts,
But rather milks them by their teats.
How doth the lichen food obtain?
The fungus, I would ascertain,
The alga probes with fingers shrewd.
His ticklish damsels something lewd,
And makes the ladies to surrender,
Unto its hands the purloined provender.
My only thoughts on the issue of whether the fungus 'eats' the algae are that  the fungi eat the products made by the algae (and they often even seem to enhance the production of food by the algae) and  the fungi presumably must devour the carcasses of the dead algae. Whether or not the fungi may, under certain conditions, 'kill' some of the algae or speed along their ultimate demise is not something that I think is known, although I would welcome additional commentary on the matter!
Lendemer, J.C. 2007. Megalaria beechingii, a new species from the southern Appalachian Mountains of eastern North America. Opuscula Philolichenum 4: 41-44.
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