Every time I sit at a bar (which doesn’t happen that often, don’t worry), I remember my lecturer in a course called Diversity of Life during my first year at university.
He talked about nematodes and how common they are. One of his claims was that if you took a tree and removed all the leaves, bark, lignin and other matter making up the tree, you could still see its ghostly outline from all the nematodes that lived in it. While this is highly hypothetical, the mental image of the ghost tree was vivid enough that I still remember it more than twenty years later.
The reason I think of this lecturer and nematodes while sitting in bars is another one of his stories: He claimed that there’s a species of nematode that only exists on beer mats. It’s plausible that beer mats are full of life: They’re constantly damp, have nutrient-rich beer spilled on them, and I’d rather not know how rarely they are washed.
Panagrellus redivivus was discovered on beer mats and for some time was only known to exist on those. Later, it turned out that it was identical to another nematode that had been described previously. I tried to trace the original discovery of the beer mat nematode back as far as I could and found this paragraph in a paper by nematode specialist Howard Ferris:
Among the interests of Professor Ludwig was the flora and fauna of so-called damp beer mats which, at that time, were thicker than beer mats in use today and made from oak pulp. One of Ludwig’s students, Carl Jahn, discovered nematodes in damp beer mats in the German town Schleusingen
(translated as Silusia in Latin). De Man (1913, 1914) described the nematode discovered by Jahn as the “Bierfilzälchen or beer felt nematode”, Anguillula silusiae, speculating that it originated from oak trees (Karssen, 2006; Gerrit Karrsen, personal communication).
Anguillula silusiae later turned out to be identical to P. redivivus. What’s not clear from Ferris’ paper is who Professor Ludwig was. The most likely candidate by far is botanist Friedrich Ludwig.
