The House of Dung

We gathered around with hand lenses, expensive cameras, and intent interest.  After some initial documentation, the specimen was reverently placed in a basket and carried back to the main hall to be further examined and identified.  Pieces were placed under microscopes, and hefty field guides were referenced. It was probably the most interesting thing brought in that day: a large pile of dung.

I recently spent a weekend in southern Washington, along the northern base of Mt. Rainer.  I was lodging near the transition between the dry rocky hills of eastern and the temperate, mossy forests of western Washington.  I was there to look for fungi with an esteemed group of fungal taxonomists called the Pacific Northwest Key Council.  Key Council members are some of the primary experts of what grows in this region. They are also the grand organizers of the complicated, and oft-contested process of applying names to fungi.  Fungi are particularly difficult in this arena – not only are they unreliable in how and when they grow, but they are also genetically complicated.  Organisms that look very different from each other are sometimes genetically similar, and some that look very similar are genetically distant.  Some that are capable of sexual reproduction also reproduce asexually some of the time. Some fungal cells house the nuclei of two genetically distinct individuals for awhile before undergoing karyogamy, or nuclear fusion.  In other words, fungal taxonomy does not lend itself to easy distinctions between species and individuals.  It’s really hard to do, and I have a great deal of admiration for people who sort through the tangled web of it.

Michael Beug, professor emeritus at Evergreen State University and member of the Key Council, has recently contributed immensely to the field of fungal taxonomy through his new book on North American Ascomycetes.  Ascomycota is a diverse fungal phylum that includes morels and cup fungi. In the northwestern spring, fungi in the Ascomycota are sometimes more common than Basidiomycota, the phylum that includes all of the gilled mushrooms.  We found some fantastic examples of ascomycetes, including this elegant Plectania nannfeltii:

Plectania nannfeltii

Photo Credit: Michael Beug

Still, there was a definite lack of abundance. This year was sparse for many species, but there was one substrate that hosted a variety of interesting organisms: dung. Dung was still a smorgasbord of fungal growth, especially one particular cluster from an elk.

Fungi and dung have a long history together.  Specimens of fossilized dung, known euphemistically as coprolites, were found containing fungal spores from the Middle Permian (over 250 million years ago).  It’s a good deal for a fungal spore- not only do they acquire a means of dispersal through the wanderings of their animal hosts, but they also are deposited in a nutrient-rich habitat.

Elk Dung Fungi

Photo Credit: Michael Beug

This one photo shows four distinct species: three ascomycetes, and one tiny basidiomycete at the top.  For size comparison, the brown object on the left edge is the tip of a pine needle and the green stalk to the right is the new growth of a conifer seedling.

Fungi, of course, aren’t the only things that make their home in this nutrient-dense feature of the forest.  Myriad organisms can be housed within a patty, from cattle nematodes to dung beetles to a thriving bacterial community. Next time you pass by some dung in the woods, it might be worth digging out your hand lens to see if anything interesting has arisen.