An Excerpt from Jim Conrad's
NATURALIST NEWSLETTER
January
26, 2014
Issued from the valley of the Dry Frio River in northern Uvalde County, southwestern Texas, on the southern border of the Edwards Plateau, USA
Nowadays with so few plants flowering it's worth paying special attention to lichens. Continually I'm surprised by lichen beauty and diversity, but maybe the most striking feature about them is something that's not immediately obvious: They're "composite organisms" consisting of two or three completely different species mingled together to form the single lichen species. It's like mixing a chicken with a dog to get a new, independent organism.
Every lichen is partly fungal. The fungus gives the lichen its form, helps it retain water and provides sexual reproduction of spores dispersed by wind and rain. Fungi don't photosynthesize, however, so a lichen's life cycle begins when the hypha from a lichen's fungus-produced spore finds cells of certain species of alga and/or cyanobacterium to wrap around or even penetrate, in order to take carbohydrates produced during photosynthesis. You could say that the fungus "parasitizes" the photosynthesizing species, except that the alga and/or cyanobacterium also benefit from the arrangement, so it's a close "symbiotic" relationship. The individual fungal, algal and/or cyanobacterial species constituting lichens often survive independently in Nature, but some species are known only as constituents of lichens.
Since the lichen-making partnership is so advantageous to everyone involved, it's easy to imagine how over time the original free-living species forming lichens could have evolved predispositions for entering the relationship,. However, why didn't evolution stop there, with lichen bodies never becoming more complex than simple crusts, like dried gravy smeared on rocks or tree stems? Once a fungus and its photosynthesizing partners have what they need in the relationship, what's the point in becoming more complex, more interesting, and more beautiful?
Lately we've seen that lichens go far beyond looking like dried, smeared-on gravy. We've seen the Sunburst Lichen's golden, leafy thalli branching and rebranching as they elegantly dispersed across twig bark; the Firedot Lichen's orangish fruiting bodies spectacularly ornamenting a white, crusty body; the Cartilage Lichen's gray-green ribbons strikingly dangling from branches like tattered lung tissue; Old-man's Beard's windblown threads really looking like an old man's white beard blowing in the wind... On and on, every new lichen species exposes us to something unexpected, maybe something bizarre, but always pleasing and beautiful.
In fact, among the lichens there's such gorgeousness and innovation of form and design that it's clear that something is going on far transcending the demands of mere functionality. Lichens are put together with flair, and passion, and maybe some kind of love.
But, once lichens start you thinking like this you realize that the same can be said of all of Nature. A commonplace tree is more of a wonder than any lichen. If we're not inspired and awed by simple walks through woods or across average fields or down regular beaches, it's because we've grown accustomed to what we're seeing. Familiarity has desensitized us, but that doesn't mean that mind-boggling gorgeousness and meaning isn't everywhere.
So, lichens remind us of at least two worthy insights. First, the Universal Creative Force not only is "productive" of diversity in the Universe, but also the Force creates with elegance, panache and maybe even humor. Second, lichens remind us that we can shake up our own lives simply by taking a fresh look at what's commonplace and normal. .