JIM CONRAD'S
NATURALIST NEWSLETTER
Written at Hacienda San Juan Lizárraga
one kilometer east of Telchac Pueblo, Yucatán, MÉXICO
and issued from Hotel Reef Yucatan 13 kms to the north

February 11, 2006

SOLAR BREAD
Most days here are sunny with afternoons so long, bright, glaring and hot that the midday siesta reveals itself as both civilized and necessary. Still, people in this area are suffering from fast-rising electricity, butane and gasoline costs, and the scrub- forest around us is being gnawed away by firewood gatherers. The cost of firewood is skyrocketing, too.

I link these thoughts because if sunlight were more effectively utilized here people wouldn't have to spend so much on energy, and so much firewood wouldn't have to be gathered.

For weeks I've been gradually gathering materials for building a TV-satellite-dish cooker such as the one I used last summer in California and before that in Mississippi. You can see those cookers at http://www.backyardnature.net/j/solardsh.htm.

Here in Mexico it's harder to find what I need for the construction, plus what I find usually costs too much. Coming up with a few screws or a screwdriver with a squared tip can become an endless, frustrating task, and just forget about finding cheap aluminum flashing.

Meanwhile I've put together a much less powerful cooker. "Put together" is more correct than saying "constructed" because really all I did was to bring together several items lying around the plantation. This new cooker consists of an old, rotting footlocker, a couple of sheets of glass removed from picture frames where the pictures had decayed, some dry straw, and a stainless steel pan no longer being used for feeding dogs. It's shown at the bottom of the page at the above link.

A chunk of dry wood placed on the cooking platforms of my two TV-satellite-dish cookers would after a few minutes begin smoking and then catch fire. Those cookers could boil water and cinderize cornbread if I wasn't careful.

This one made of found parts is incapable of such pyrotechnics. However, it certainly can fry eggs, bake bread and, most deliciously of all, roast bananas to a sweetness at least comparable to that of bananas roasted in the embers of a campfire. It will not, however, bake potatoes or carrots, or bake beans to mushiness.

I'm sure others have thought of my design before, but I've never seen it described anywhere. I call it a "double cooker" design.

The usual box-style cooker consists of a well insulated box with a tight-fitting glass top, black interior walls, and reflective panels mounted outside the box for bouncing sunlight into the box. The system depends on the greenhouse effect. Solar energy entering the box is absorbed by the box's black walls and the food. Energy builds up inside the box because the glass top keeps it from escaping.

My "double cooker" design consists of one cooker inside another, each with its own glass top. Instead of relying on good insulation and tight seals, which is hard to accomplish here, I heat the environment outside the inner cooker, thus decreasing the heat gradient between it and the outside air, and slowing down heat loss from the cooking part.

I'm showing this concept to any of my neighbors who will look. If more people would do at least part of their cooking with such simple, easy-to-construct cookers, they'd end up with more money in their pockets, and the forest would be a bit less weedy and ragged looking.

*****

FIDDLER CRABS
You see them at low tide where the water has withdrawn from the dark mangrove wall surrounding the lagoons, leaving extensive mud flats. Especially you see them where Black Mangrove roots sprout thousands of slender, gray-brown, pencil-like, oxygen-absorbing pneumatophores up through the mud surrounding the trees. There scooting sideways across the mud down in the knee-high pneumatophore jungle you'll see fiddler crabs, sometimes just one or two, but sometimes thousands, incredible cities of them sitting quietly until you make the wrong move, and then they all stampede in Alfred-Hitchcockian single-mindedness.

The feature making them fiddler crabs and not just crabs is that one of the male's two claws is much, much larger than the other claw. (The technical name for a crab's claw is "cheliped.") Hermit crabs also bear one oversized claw, but hermits live in abandoned seashells, for their bodies are not well protected with armor. Hermits use their big claws to close up their shells' openings when they retreat into the shells. I've not seen hermit crabs here but I'll bet a snorkeler surveying the sandy floor just offshore would see one.

Male fiddlers eat with their small claw while holding the large claw before them -- like a fiddle. As the small claw moves back and forth between the ground and the mouth, it looks almost as if the crab were sawing at his fiddle with a bow. You can see an animated GIF demonstrating this action, and find links to other fiddler pages, at http://www.fiddlercrab.info/

Fiddlers eat algae and other organic material their small claws can handle. The male's big claw is used for impressing females and for flaunting when competing with other males for territory. If a big claw is lost, a small one replaces it. Fiddlers dig tunnels in the mud or sand and stay there during high tide. This means that they feel at home both above water and out of it.

About 65 species of fiddler crab are known. I've seen two or three species here but I don't know which they are, though all fiddler crab species appear to belong to the genus UCA.

*****

SPINY CUCUMBERS
Nowadays in dry, sandy soil along weedy roadsides sometimes you come upon scatterings of what appear to be a dozen or so brightly yellow-green, spiny eggs lying randomly on the ground. When you pick one up you see that the objects are actually fruits attached to withering, scabrous vines, and that the prickles are soft. In fact, they're something like cucumbers. I brought one home this week and photographed it. It's at http://www.backyardnature.net/yucatan/cucumber.jpg.

These fruits are almost cucumbers, being not only members of the Cucumber Family, the Cucurbitaceae, but also of the Cucumber genus, Cucumis. They're CUCUMIS ANGURIA, which my books call West India or Bur Gherkins, though I can't imagine regular people calling them anything but Spiny or Prickly Cucumbers. They taste almost like garden cucumbers, but they're filled with so many plump, fairly hard seeds, and possess so little firm flesh that I doubt many people would eat them unless they were hungry. I've eaten them, including the one in the picture, but the seeds sure are scratchy going down.

The species grows from Florida and Texas south through Mexico and Central America to South America. Some gardeners grow it as a curiosity, and I read that despite the seeds they can be pickled. Though botanically they're known as "gherkins," the gherkins of commercial mixed pickles are usually young cucumbers (Cucumis sativus).

*****

A FRUITING CYCAD
Among the interesting plants established at Hacienda San Juan by the previous owner are some cycads. One is fruiting now, and you can see it at http://www.backyardnature.net/yucatan/cycad.jpg.

Except for its fruiting body, this particular cycad species looks like a large fern. Ferns reproduce with spores, however, and you can see that this fruiting body is a cone, almost like a pine cone. "Cone" is the right word, too, because cycads are gymnosperms, just like pines, spruce and firs.

One reason it's so wonderful to have cycads on the grounds is that MOST of the 289 or so cycad species on Earth are threatened, endangered, or no longer living in the wild -- known only from garden plantings. This is an unhappy state of affairs for a group of plants that reached its greatest period of abundance and diversity during the Age of Dinosaurs. Cycads are very primitive kinds of plants.

They come in male and female plants, the pollen being produced in male cones. Many cycad species are pollinated by insects, and it's interesting that usually the insects belong to primitive families. Typically the pollinators mate and lay eggs inside the female cone. It's believed that this reflects the fact that cycad pollination evolved before flowering plants appeared on Earth. Everything seems to point to the cycad's evolutionary antiquity, making them almost like living fossils.

I'm unsure which cycad species we have here but I'm guessing it's a member of the genus ZAMIA. In the old days there was just one Cycad Family, but now three are recognized: The Cycadaceae, Stangeriaceae, and the Zamiaceae.

You can read a lot more about cycad botany at http://www.conifers.org/cycadales.htm.

The Cycad Society provides a page with over 80 thumbnail pictures you can click on to enlarge at http://www.cycad.org/photos.htm.

*****

MATT'S BUG-EATEN LEAF AWARD
This week I was gratified when Matt Schelke in Philadelphia sent me a list of 33 plants and animals he'd identified in his neighborhood, thus qualifying for my Bronze Level Bug-Eaten Leaf Award. His list is at http://www.backyardnature.net/awards/b-pa-001.htm.

The Bug-Eaten name of the award was chosen in order to remind us that in nature everything connects to everything else -- that bugs eat leaves, birds eat bugs, what comes out of birds fertilizes trees producing leaves eaten by bugs, etc. Since my website statistics show that thousands visit the site every day -- up to 26,000 when kids everywhere are working on term papers -- I'd thought that I'd be issuing lots of awards. I'd visualized the awards pages as becoming interesting to browse, to see what people were finding in their backyards all over the world, and I think there's still that potential. However, though I've been offering the Bug-Eaten Leaf Award for a couple of years Matt is only the second to send me a list.

Identifying 33 plants and animals in one's own neighborhood still makes a fine project, so I hope you'll keep it in mind for your own student, or for yourself, as spring comes on and your outdoor juices start stirring.

It happens that Karen, my friend in Natchez, has begun identifying critters visiting her yard. She has seven species so far, which is a good start. She writes:

"While doing research on my little habitat, I found an excellent site to help me. It's called E-Nature. You can type in your zip code, so that helps isolate what is actually in your area."

That site, sponsored by the National Wildlife Federation, is at http://www.enature.com/home/.

*****

A DOG WITH BLUE-GRAY EYES
One afternoon this week while Vladimir and I did our botany in the Pavilion, a wild-eyed, hungry-looking, hair-matted, stinking dog stumbled from a clump of palms, climbed onto the Pavilion and stalked around as if looking for something. I think he was a young Siberian Husky, with bright blue-gray eyes set wide apart in a white face. That's unusual for around here, since dogs here interbreed so casually that most show no identifiable breed affiliation. This dog's rear end kept collapsing, apparently because he'd been hit by a car. He was as pitiful as you can imagine and those bright blue-gray eyes bore right into us.

Though unusual as a Mexican dog breed, he was exactly right in terms of being abandoned, hungry, and in a bad shape. The landscape here swarms with starving dogs. You hear packs of them howling deep inside the scrub at night. In large numbers they hang around informal roadside dumps, frequently fighting over scraps.

Of course the ideal is for fewer dogs to exist, and for the ones we do have to be loved and cared for. It would seem such an easy thing to do, to sterilize dogs who shouldn't reproduce, or at least to keep females inside or tied up when they're in heat.

But, how can we expect more civilized treatment of dogs when humanity often treats itself no better? Think of all conflicts going on right now mostly caused by competition for natural resources, just as with the dogs at our roadside dumps. Consider how George Bush's new budget shifts moneys from already stressed social and environmental programs to the military.

One is tempted to think that basic Darwinian evolution is at work here. Whenever a species' population attains a very large distribution, it fragments into races and subspecies, and finally new species emerge. Could it be that right now we humans are evolving into subspecies of "haves" and "have nots"?

This will never happen, if only because the living strategies of the "haves" is unsustainable. There isn't enough breathable air on Earth, not enough productive land, not enough fish-producing sea, and not enough moderate weather to maintain consumption- obsessed "haves" long enough for them to become a subspecies. Nor will bomb-possessing "have-nots" permit "haves" to enjoy their indulgences for so long.

In the end, for the sake of Life on Earth, today's "haves" and "have-nots" will have to meld into a population consisting of fewer people living more equitably and much more sustainably than most of us live today.

Else, the future belongs strictly to the "have-nots," for their living strategy is most sustainable. And even their survival will be possible only as long as their population numbers stay within bounds -- a dynamic historically regulated by war, disease and famine.

It would seem so easy to make better lives for dogs, and for ourselves. However, something in human nature keeps us from doing the simple things clearly needing to be done -- controlling our numbers and our appetites, sharing resources, empathizing with one another and other living things around us.

The blue-eyed dog with starvation in his eyes may become the prophet of our time simply because we are willing to let it happen.

*****

Best wishes to all Newsletter subscribers,

Jim

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