Dicromantispa interrupta

Dicromantispa interrupta

Tuesday, December 28, 2010

Gwion Gwion

Being a professional naturalist and amateur anthropologist who loves art, I am especially fascinated with Pleistocene paintings in European caves. I believe the artist that painted on the walls of Chauvet Cave in France (http://tinyurl.com/36vmdgs) was a genius of ability comparable to recent artists.

I have to admit, however, that the prints on desert rock walls in Australia and the American Southwest seem to me to be little more than palm prints and stick figures. I realize they actually represent much more than that, that they are significant to their cultures and are worthy of the highest degree of protection, but I do not consider them art for three reasons. First, an artist must master his medium before he can make art, whereas these primitive applications of pecking, charcoal and red ocher hardly compare to the talent that Lascaux and Chauvet Caves illustrate existed in ancient times. Second, art transcends culture, whereas this genre has meanings specific to particular cultures. Third, its creators may or may not have had “art” in mind when they drew the images, thus eliminating it from consideration as art by definition. Australian Aborigines call it “gwion gwion,” and perhaps that (or the single word, “gwion”) is a better name for it.

But now comes a scientific discovery involving Western Australia’s Bradshaw rock art that gives a new dimension to those paintings (http://antiquity.ac.uk/projgall/pettigrew326/). It turns out that in some cases the paint has been replaced naturally by “a biofilm of living, pigmented micro-organisms whose natural replenishment may account for the longevity and vividness of these paintings.” Some gwion gwion, however, are not infected, so their colors fade. These may be repainted several times over the centuries.

I can imagine going back in time to visit a gwion gwion long, long ago, right after it was painted by a shaman and revealed to his tribe. For a time, the colors were bright and the characters distinct, but after a while they began to fade. The old shaman noticed this and planned to repaint them, but when he took another look, he noticed the colors were changing and becoming more vivid than the original tints. He did not know that microscopic bacteria and fungi colonized and replaced the paints and were responsible for the transformation. It must have appeared to him to be a miracle from heaven, and with the proper presentation, his followers thought so too.

I have an artist friend named Tom Glover W., one of the world’s greatest living wood sculptors, but he has abandoned the wood medium for harder stuff like marble and steel. I don’t know why he has done so, but I can imagine being able to create excellent art and wanting people to be able to appreciate it for a long time. Wood will, after all, crack and rot after a century or two. I have seen Tom’s wood work languishing, dusty and cob-webbed, in an unkempt pawn shop. Oh, the horror…

Envision an artist deliberately using microorganisms in his work, bugs that can withstand the ravages of weather and time while displaying everlastingly bright colors and patterns and perhaps also interesting textures and aromas. This could give artists a new medium to master, and I bet they’d do some awesome, ingenious things with it. One can only hope that microbiologists will expand on this discovery and create a palette of organism-colors for artists to use.

Monday, December 27, 2010

Rainy Day Science Reading

Yesterday was cold and wet out, and in fact, it actually snowed for a few minutes around 10 am, so I stayed in and caught up on my reading. Too bad the snow was so ephemeral, as I wanted to photograph it. The top of my RV’s “porch” awning iced up in the brisk wind, though.

A layman’s article in the journal Science (Australia to test ‘mosquito vaccine’ against human disease, 10 Dec. 2010, vol. 330, p. 1460-1461) discusses a fascinating approach to dealing with mosquitoes carrying serious diseases of humans. The idea is to infect mosquitoes with the bacterium Wolbachia pipientis, which has the ability to keep mosquitoes from being infected by human-disease organisms. The Australians have succeeded at infecting the vector of dengue, Aedes aegypti, with Wolbachia in cage trials, and now plan a field test in Australia. If successful, they want to try it next in Vietnam and then possibly Thailand. Dengue is a viral disease in humans that causes crippling joint and muscle pains, so the possibility of eliminating it is exciting.

Wolbachia has a very effective way to spread rapidly within a population. All infected female mosquitoes pass on the bacterium to their young, but when uninfected females mate with infected males, there are no viable young. It took only two decades for Wolbachia to infect a fruit fly species, Drosophila simulans, around the world.

The article stated that Wolbachia-infected mosquitoes are resistant to causative agents of some other important diseases, namely elephantiasis and chikungunya, and even inhibits some species of Plasmodium parasites that cause malaria. Unfortunately, the major disease-carrying mosquito species are not infected by Wolbachia, so the Australians want to give Wolbachia a boost up. No genetic engineering is involved and the bacterium already exists widely in the wild, so researchers believe that environmental concern re the release will be minimal.

Some mosquito species carry Wolbachia and do not carry human diseases whereas other mosquito species do not harbor the bacterium but do carry human diseases. This being the case, it begs the question of why Wolbachia does not already infect disease-carrying mosquitoes. Is it possible that the disease organisms of those mosquito species have already evolved ways to defeat Wolbachia?

There’s another interesting article in the 12 November 2010 (vol. 330, p. 932) issue of Science entitled “A wandering mind is an unhappy mind.” Yep, that’s really the title of a serious research paper in one of the world’s most prestigious scientific journals, and it caught my eye and I bet you know why.

There were three basic findings. First, people’s minds wander frequently almost regardless of what they are doing. Second, people are less happy when their minds are wandering than when they are not. Third, what people are thinking is a better predictor of happiness than what they are doing. The authors stated, “… a human mind is a wandering mind, and a wandering mind is an unhappy mind.” You could bring up the Devil and idle hands if you want to, but to me it rather sounds like Mother Nature giving us yet another insistent incentive to do better. Not a bad thing to realize a few days before the New Year.

Sunday, December 26, 2010

San Felasco's Mideast

Twice recently, I hiked into a part of San Felasco Hammock Preserve State Park that I have never before visited, traversing 6.2 and 9.9 miles. That area is along the eastern boundary about half-way between Millhopper Road and the park’s NE corner, just about as far from either trailhead as you can get. The first occasion was a reunion with a friend and former co-worker from the 1970s and early 1980s, and the second was solo. Aside from enjoying good company and good woods, the missions on both expeditions were to continuing documenting the locations of sinkholes and trails. This aerial photo depicts the GPS tracks of the two hikes and the general polygon of interest (white polygon):

A couple of days before the visits, I finally took the time to read the 2005 land management plan for the park (http://tinyurl.com/23opnbv). I was encouraged by the overall direction being resource-based recreation and conservation as opposed to timber management or a single-species/habitat orientation. In other words, the plan is to restore the native plant and wildlife communities that occurred on site in pre-Columbian times and allow citizens to make passive recreational use of it. Notably, the authors recognize the hammock as the largest and best example of this habitat type remaining in Florida.

The plan also contains a map of the park’s major plant communities and a base map of its roads and trails. The latter is much better than any other map I have seen of San Felasco, either on-line or as a hard copy trailhead give-away. Unfortunately, the two maps are not at the same scale, and the vegetation map has no trails on it to use for orientation. In fact, all other maps of the park are also frustrating in that regard. USGS Topo Quads that are as wrong as they can be.  The county publishes much better topos, in 2-ft contour intervals, but those covering San Felasco are at two different scales, one for areas within the Fernandez Grant and another for areas outside that old Spanish land grant; Google Earth provides aerials at odd scales that do not match any other map; and my Garmin GPS uses the incorrect USGS at still different scales and oddball contour intervals, plus it contains roads that have never existed. We’ll just have to wait until my map comes out before we have available a map with accurate topography, trails and plant communities, all at a single scale.

The mixed forest in that region may be the best of the park for several reasons. It is dominated by climax forest species like Southern magnolia, live oak, Florida maple, pignut hickory and mockernut hickory, although pioneer species like sweetgum, laurel oak and spruce pine are common. Another reason is that it seems to me that the trees here might average a little larger than in other parts of the park. Dan and I encountered a large bluff oak (Quercus austrina), for instance, larger than any I have ever seen (and I keep an eye out for champion trees). Here’s a shot of Dan with the bluff oak on the left:

Incidentally, the park plan mis-identifies this species as the bastard oak (Quercus sinuata var. sinuata), unless the taxonomy of the taxon changed while I wasn’t looking; not being a botanist, that could well be the case. Here I am peering into a hollow laurel oak trunk to see what I can see – no critters this time, though:

The large black willow I mentioned in a post a few weeks ago is within this region. The uplands here have more exposed limestone than elsewhere in the park and two species of rare ferns. Finally, this region has no park trails and is distant from trailheads, so human visitation here is almost certainly at a minimum. One of the stated goals of the park plan is to provide a wilderness experience, and this particular area certainly does that.

The sinkholes are very different, too. In general, they are larger, deeper and support more vegetation and wildlife than sinkholes elsewhere on the park:

The relatively large marshy pond located in the lower left quadrant of the aerial is called Dahoon Pond, named after the dahoon hollies (Ilex cassine) ringing its perimeter. It is primarily a maidencane (Panicum hemitomon) marsh, however, being almost 100% dominated by that grass. Below is a shot of the maidencane, illustrating it as a monoculture, and also showing one of the small clearings within the dense grass. I have no idea what caused this denudation, although I rule out feral pigs because the ground was not torn up and pigs are not grazers. They are no deeper than the surrounding marsh bottom, so water levels have nothing to do with it. The maidencane stubble almost appears to be carefully clipped, but by what? Capybaras?

I’m enjoying the extra dollop of wildlife that occurs in San Felasco at this time of the year. Ordinarily lucky to see a single flicker once every couple of years, for instance, on the second trip I saw two of them. Dan and I noticed some kind of animal making waves in Blues Creek that disappeared before we could identify it, but on the second trip, I saw several small flocks of wood ducks in the stream. Other notable observations were a flock of yellow warblers with a token black-and-white warbler, a flock of cedar waxwings, a chuck-will’s-widow and possibly a whippoorwill.

I almost misjudged my exit timing on the second trip, and had to boogie to get out of the woods before darkness fell. I had a small headlamp with me, but when alone in the wilderness it is a good idea to have backups.