See, if you tilt the camera, the rocks slide downhill. Wait. . . let me check my notes . . . A photograph of the fascinating Racetrack Playa in Death Valley, California, USA. Creative Commons djfrantic. Click for link.

It turns out there’s a perfectly cromulent explanation for this effect; if you don’t know it and want to spoil the magic, see here.

Well, it turns out that this organism,

Sooooooo cute. I'm waiting for the plush version from Etsy. Grimmia trichophylla. Creative Commons johndal.

or one of its close relatives, I should say, can apparently do the same, or something like it. Don’t believe me? There were three photographs and a fascinating account of the phenomenon over at Botany Photo of the Day last week — the most important bits are paragraphs two and three. Don’t miss it! Once you’ve read it, come back here for a little commentary . . .

OK, finished?

Now, my friends, you can see why geologists hate “vegetation”. For in addition to your garden-variety and annoyingly rock-obscuring trees, shrubs, flower, and soils, they must also contend with the biofilm of lichens — little fungus-alga co-ops — and naked algae that encase every rock in sight after a few decades. That means that nearly every rock face you look at is not its true color; it’s the color of the encrusting life. The day the light bulb blinked on and I thought, “That cliff isn’t gray-green. The rock is pink and the stuff living on it is gray,” was one of revelation for me.

This further explains why geologists flock to newly blasted road cuts like flies to honey, and further why they carry around rock hammers* for splitting rocks to see what they truly look like. It also explains why I get nervous around them when they get that glimmer in their eyes suggesting that if they could napalm the countryside in their research area, they would.

When I reach the summit of mountains in Colorado, I’m astounded by the variety of lichens, moss, and algae I find there. Mountaintops are lichen biodiversity hot spots, splashed with green, yellow, black, gray, and orange.

A fiesta of lichens (can I coin that term for a lichen herd?) at Rocky Mountain National Park. Creative Commons shrocket.

Thrillingly orange lichens are particularly common up there, since they thrive in places birds poop (and thus fertilize), and birds seem to like perching on rocks near the summits of mountains where they, like us, have a clear view of the countryside. And yet, almost no one looks down or looks carefully, and with enough foot traffic, the encrusting life dies and peels off.

Apparently, mosses can also induce lichen holocausts as they slide down rock faces. How they do this, I know not, although the lack of light may play a role. But notice there aren’t simply dead lichens in their wake; the rock is scrubbed clean. Which leads to another interesting hypothesis: the moss excretes acids or some other chemicals that allow them to digest the biofilm on the rock surface and absorb the resulting nutrients. Would that make these mosses . . . herbivores?

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*Also because physical and chemical processes called “weathering” alter the surfaces of rocks. Also, by coincidence, they note that in the first two photos of the galloping moss, they are galloping upon the fossils of 1.9 billion year old cyanobacterial mats — thin films of blue-green bacteria that slowly build up characteristic striated rocks called stromatolites. In ancient times, these were prolific and their fossils are common, but today, stromatolites, crowded out by us pesky multicellular organisms, are found in only a few places on Earth, most prominently in the Hamelin Pool in western Australia’s Shark Bay. Interesting biological coincidence!

Living on the moist, warm ground were moss and liverwort gardens 30 feet across. Wait. . . liverwort? Liverworts are amazing moss relatives that can produce leathery lichen-like bodies with an emporium of odd-looking reproductive structures. They’re called liverworts because supposedly, their odd protuberances can resemble livers. In medieval times, people thought that if a plant looked like something, that was God’s way of telling you that it was good for treating it, a philosophy called the “Doctrine of the Signatures”. So if your liver was ailing you, you might get a tincture or powder of liverwort to take. As it turns out, that’s not such a great way to identify potential drug candidates, but I digress. . .

The geeky-cool liverwort, likely Marchantia of Botany 101 fame. http://www.flickr.com/photos/benetd/ / CC BY 2.0

The most well known liverwort — Marchantia — makes fake-palm-tree-like female reproductive stalks and nail-like male ones (not pictured). It’s such a successful little guy that this species has even become weedy. When I worked at a garden center one summer after graduating college (yes, the first job I got with my shiny new bachelor’s degree was weeding and watering plants) it was not uncommon to find liverworts crowding the soil at the base of a plastic pot. Apparently the twice daily (at least) watering routine at plant nurseries agrees with them.

In the wild, these little plants are often found growing near brooks, even here in Colorado, where I have seen them (uncommonly) growing next to streams in Rocky Mountain National Park. In the above picture, you can see another of their crazy reproductive structures, asexual gemma cups. They look like little bird nests. In the cups, little lens-shaped or spherical tissue packets called gemmae are formed asexually. When raindrops land in them the gemmae are splashed out and land on soil elsewhere. If they start growing and take root . . . voila! New liverwort.

The leafy liverwort Jamesoniella autumnalis. Used with permission courtesy of Robert W. Freckmann Herbarium, University of Wisconsin, Stevens Point.

However, that’s a thalloid liverwort. The leathery projections in the photo above are referred to as a thallus or thalli (pl.), because they are undifferentiated (into leaves, stems, etc.) plant tissue. But there is a second type of liverwort: leafy. That’s probably a bit deceptive because mosses and liverworts (a group referred to as bryophytes) don’t have true leaves, shoots, or stems, a botanical nicety whose explanation I will spare you for now. The liverworts found atop Socompa appear to be of this type. When scientists sequenced part of their DNA, they found they were most closely related to a species called Jamesoniella autumnalis, which can be found in North America. Here is a picture of one found growing in Wisconsin.

And here are its crazy reproductive structures:

Can you get PBS with those? The sporophytes (spore making plant) of Jamesoniella autumnalis. Used with permission courtesy of Robert W. Freckmann Herbarium, University of Wisconsin, Stevens Point.

To keep this post from turning book-length, I’ll merely mention that, believe it or not, the pointy-looking things you are looking at in this photo are a completely different organism of the same species as the plant they are growing out of. Plants do an amazing thing called “alternation of generations” in which they alternate between haploid (one copy of genes) and diploid (two copies of genes) organisms. All plants do this — even petunias and apple trees. Where is the second plant of those species? Ahh . . . I’m glad you asked. But that shall have to remain a mystery for another day. : ) In this case, the green thing underneath has single chromosome copies, and the pointy things above have the dual, and their sole purpose, as they parasitically grow out of their parent plant, is to grow tall enough to broadcast the spores they are making inside those little black heads.

The mosses that were found on Socompa were related to the copper moss (love that name!) Mielichhoferia elongata which, as far as I an tell, look pretty much like your standard moss but tend to grow on copper-rich rocks. That’s not surprising, given that a few miles west of Socompa is — the Escondida Copper Mine. Mosses also have alternation of generations and a beautiful but somewhat less eclectic selection of reproductive structures, but I will save that discussion for another day.

It’s unsurprising to find mosses and liverworts at such a spot on Socompa because mosses and liverworts are what biologists would call “ancestral” — that is, they more closely resemble the common ancestors of plants than conifers or flowering plants do. They are of a form that is necessarily tied to water, since those ancestral plants had only recently left the oceans. In fact, mosses and liverworts cannot live without flowing water during at least part of their lives, because to make that pointy thing (called a sporophyte — or spore plant), a sperm has to swim out of the boy-part of the plant through a film of water on the surface of the plant to find the girl part of the plant. How’s that for sperm mountaineering? But aside from their need for water, bryophytes are quite hardy. When the first plants sprouted out of the seas, land was probably a forbidding, empty, UV-drenched place. Sound familiar?

I’m going out of town today, but next week I’ll be back with a look at some other great critters from Socompa.

What’s even better are the AWESOME MOSS BIOREAKTORS they used to do it!

Is that Luke Skywalker in there? The only thing that could possibly make this image more awesome would be some lightning shooting out of the tops of those reaktors (cannot help self -- the Germanic K is too much fun). Eat your hearts out, nuclear physicists! Click image for source.

Now I ask you, does it get any cooler than bionic moss? Although this does beg the question: Why, on God’s Green Earth?

Because this bizarre, dissociated, barely recognizable moss could provide a cheaper, easier and more economical way to produce drugs like insulin. Right now such proteins are produced in relatively costly and difficult-to-maintain mammalian cell cultures with organic vegan-class nutritional and environmental requirements. Only industrial countries can handle the complexities, and demand is outstripping supply.

Moss, on the other hand, makes its own food. All it needs is some light, a few inexpensive salts, water, and room to grow. Have Chlorophyll — Will Transcribe. A simple growth solution also makes purification of the product protein much easier, according to the paper. With such a set-up, even developing nations may one day be able to make insulin for their own diabetics. Yes, better living through biokemistry. : )