May 16, 2010
A SPREADWING SKIPPER
Nowadays most afternoons the temperature breaks 100°F (38°C). The rains we had a couple of weeks back suddenly ended so now all the greenness I've been bragging about is getting a bit wilted and some leaves are showing brown edges.
Still, plants and animals "know" that if rains are going to come this year they'll be coming soon, and it's surprising how many new creatures are appearing that I've not seen before. That was the case this week when a certain dark butterfly became rather common in a single day, despite my not having noticed it for the last six months. You can see it at http://www.backyardnature.net/n/10/100516sk.jpg.
I sent the picture to volunteer insect-identifier Bea in Ontario, remarking that it had the body of a skipper but didn't hold its wings at the 45° angle that so many skippers do. Bea replied, "Don't forget that there is a subfamily of skippers called 'spreadwings' that hold their wings open like that." So this turns out to be one of the "spreadwing skippers," the Common Spurwing, ANTIGONUS EROSUS.
The species is distributed from Mexico through Central America into South America.
SATELLITE SPHINX CATERPILLAR
The other day I ran into the pretty caterpillar shown at http://www.backyardnature.net/n/10/100516ss.jpg.
Bea quickly pegged this as a Satellite Sphinx caterpillar, EUMORPHA SATELLITIA, and she further pointed out that a fair number of links to photos of the caterpillar on the Internet... are my own. For, back in Querétaro we ran into this species, though that caterpillar was dark chocolate brown, not green. Our page featuring the Querétaro caterpillar is at http://www.backyardnature.net/q/sphinx-c.htm.
Bea also copied from somewhere the following text:
"As the larva approaches maturity it changes to a reddish brown color, and after passing the third moult entirely loses the caudal horn, which is replaced by a glassy eye-like spot. The mature larva when in motion, will measure nearly four inches in length, but when at rest it draws the head and two adjoining segments within the fourth, which shortens its length nearly an inch, giving it a very odd appearance with its anterior portions so blunt and thick."
The Querétaro caterpillar must have been an older one photographed during its later stages of development, while the one found this week was a younger, greener one. A really nice shot of the green one's head is at http://www.backyardnature.net/n/10/100516st.jpg.
That picture shows some interesting details. For example, note the incurving, sharp-pointed legs below the head. Those are "thoracic legs," the caterpillar's "real" legs, of which there are six, to be contrasted to the more numerous (ten on our caterpillar), much larger "abdominal prolegs" arrayed along most of the caterpillar's length, below.
In the mouth area, notice the downward-pointing thing looking like some kind of electrode emerging from a thick, green base. It's facing the camera's lens head- on. That's an antenna and it has a sense of smell. Notice how it's positioned perfectly to monitor the odor of whatever is being chewed on.
My Maya shaman friend José, seeing the picture, tells me that the Maya name for the green stage translates to the Spanish "Cigarra de Sol," which prettily translates to the English "Sun Cicada."
For some reason one of the most popular pages at my backyard nature site is the one on earthworms. On that page I'm pretty positive about them. I quote Charles Darwin who wrote of them that "...it may be doubted if there are any other animals which have played such an important part in the history of the world as these lowly organized creatures."
To emphasize how active earthworms are in soil as they loosen it up and enrich it with their droppings, I quote a study that showed that each year on an acre (0.4 hectare) of average cultivated land, 16,000 pounds (7200 kg) of soil pass through earthworm guts and are deposited atop the soil -- 30,000 pounds (13,500 kg) in really wormy soil! That page is at http://www.backyardnature.net/earthwrm.htm.
Then this week a letter from Karen Schik in Minnesota, an ecologist with the environmental group Friends of the Mississippi River, wrote to point out that "large portions of the northern part of the continent did not have any native worms since the last glaciation, about 10,000 years ago. And yet we had a succession of marvelously diverse plant communities that have covered the land. We now have about 15 species of non- native worms that are wreaking havoc with our natural communities. You can read about it here.
She described earthworm problems in her area as well as that vast forested region of Canada covered by glaciers during the last ice age:
"Not only are we losing our native woodland flora, but when the earthworms cause their demise and subsequent bare soils (which causes erosion), it opens the door for non-native invasive species such as garlic mustard, buckthorn, honeysuckle and narrowleaf bittercress, leaving little opportunity for the native species to recover, along with the many native wildlife species that rely on them. Our trees have what one researcher refers to as 'tree gingivitis' -- the root crowns are exposed due to the removal of several inches of duff and soil compaction (yes compaction) by earthworms."
Now on my Earthworm Page, after boning up on the issue, I've added the following:
"Without worms, fallen leaves decompose slowly, creating a spongy layer of organic 'duff.' The duff isn't really soil, but many organisms depend on duff being there for their survival."
And then I include Kathy's dire observations.
I'm such a believer in earthworms, though, that I suspect that if glaciers hadn't killed the worms up North, after the glaciers receded worms would have aerated and enriched the soil to such an extent that today the forests covering the wormy soil would be much more species-diverse and productive than they currently are. Northern forests I've visited always strike me as supporting amazingly low species diversity -- compared with forests farther south.
But, who knows? What's certain is that just about anything humans do, such as introduce alien earthworm species into an area, causes problems. That's almost the definition of Nature, though -- that everything is linked to everything else, and messing with any one part causes ripple effects that spread throughout the ecosystem, causing unforeseen changes everywhere.
BARBADOS CHERRIES RIPE
Last November I introduced you to the Barbados Cherry, sometimes called Acerola, MALPIGHIA GLABRA. At that time it was flowering very prettily, as you can see at http://www.backyardnature.net/yucatan/barbados.htm.
Now the Barbados Cherries are heavy with crimson fruits, looking very much like 15-ft-tall crabapples up North. Even the trees' leaves, much-branching stems and flaky trunk look like those of crabapple. You can see a handsome branch of them at http://www.backyardnature.net/n/10/100516mp.jpg.
The fruits, which are three-seeded drupes, are about half an inch across, are fleshier than crabapples, and better tasting -- a little like overripe apple, maybe. The main problem with ours is that every one I bite into is wormy. That's a shame because the drupes are produced in abundance and they're so tasty that one wants to just gorge on them, whole mouthfuls at a time; having to remove the worms slows things down.
Earlier when we looked at the flowers we made much ado about the large, yellow pairs of glands attached to the back of each flower's sepal. Brown, dried-up, gland-bearing sepals still subtend the current drupes, as shown at http://www.backyardnature.net/n/10/100516mq.jpg.
HABIM TREES FRUITING
In the recent April 25th Newsletter we saw how the Habim trees -- also referred to as Jabim, Jabin, Fish- Poison Tree and a host of other names -- were so heavily and prettily flowering that they looked like oversized plum trees in full flower up north. Our Habim page showing that halfway down the page is at http://www.backyardnature.net/yucatan/jabim.htm.
Now those trees are fruiting and the fruits just as splendiferously transluce sunlight as earlier the flower clusters did. You can see a picture of this taken by my friends Jim and JoAnn -- who live near here and have a telephoto lens that reaches into treetops better than mine -- at http://www.backyardnature.net/n/10/100516jb.jpg.
Most people interpret what's shown as flower clusters. However, they're clusters of very unusual fruits. Since Habims are members of the Bean Family the fruits are legumes. The dangling legumes themselves are very slender, but each legume bears four paper-thin, fin- like "wings." A typical four-winged legume with its pedicel emerging from a cuplike calyx is seen at http://www.backyardnature.net/n/10/100516jc.jpg.
On our Habim page linked to above, in the first section the name Fish-Poison Tree is explained, and some of the tree's many medicinal qualities are mentioned -- also that the wood is exceptionally hard. This is an important, interesting tree.
ANOTHER CLIMBING MILKWEED
About 20 years ago at this time I was on expedition in Madagascar, looking for a certain kind of plant for scientific study. The plants were wiry little vines with mouse-eye-size flowers, members of the Milkweed Family. At the University of Bayreuth in Bavaria, Germany, I used to draw flowers of this plant group, for scientific journals. Therefore, nowadays whenever I see a member of the group here, it brings back nice memories, and I want to know which species it is. They're hard-to-identify little plants so usually I just ship a picture to my friend Ulli back at the Uni in Bayreuth, and he does the work.
That happened this week with the flowering vine shown at http://www.backyardnature.net/n/10/100516md.jpg.
If you break one of those leaves, copious white latex oozes out. The flowers are fragrant, smelling a bit like vanilla. A flower close-up is shown at http://www.backyardnature.net/n/10/100516me.jpg.
Ulli says it's MARSDENIA COULTERI, and after drawing what must have been around a hundred such flowers (while peering through a binocular microscope at tiny details) I can tell you that an unusual feature of the flower is how the white stigma head emerges above the dark brown anthers around it like a little mountain of snow. Also, the petals in this species are unusually hairy.
You can see how hairs at the flower's center point downward, encouraging visiting pollinators to continue down toward the corolla base, to do their pollinating business. However, why do hairs at the petals outer ends point in an opposite direction? I'm guessing that just before the blossoms fully open, when the petals are erect, the upward-pointing hairs dissuade pollinators from entering the flower before the sexual parts are fully mature.
I doubt many folks in the Yucatán ever notice this modest little vine but I'm featuring it in the hope that someday the pictures and the fact that I've found it here will interest a future researcher.
By the way, now they've sunk the entire Milkweed Family, the Asclepiadaceae, into the Dogbane Family, the Apocynaceae.
CELEBRATION OF SAN ISIDRO LABRADOR
The old church in whose storeroom I lived for nearly six months is named after St. Isidro, and Saturday in the Catholic calendar, I'm told, was St. Isidro's day. The old church was cleaned and prettied up, long lines of colored plastic triangles were strewn gaily flapping in the wind all around the grounds, and local folks from beyond Pisté to beyond Xcalacoop were invited to attend a special mass, and eat some local dishes served at these kinds of gatherings. Very loud, exploding rockets were set off throughout the day Friday to let people know they were welcome.
Special Maya ceremonies also were conducted. A traditional Maya belief is that the celebration is to encourage rain. St. Isidro is the Corn and Rain God.
You can see San Isidro being carried at the head of a procession toward the church, with Hacienda Chichen's main mansion building in the background (I helped decorate San Isidro myself... ) at http://www.backyardnature.net/n/10/100516_1.jpg.
A center point of the fiesta is the eating of a famous dish from the Yucatán, Cochinita Pibil, a whole pig wrapped in banana leaves and roasted in an earthen pit. My friend Lorenzo carries the pig's head at http://www.backyardnature.net/n/10/100516_2.jpg.
An important Maya part of the ceremony is carrying the pig's head in a circle thirteen times. My friend Bibiano, who gives birding tours here and plays Mexican music for guests, leads the dance at http://www.backyardnature.net/n/10/100516_3.jpg.
Maya musicians provided music from the shade, shown at http://www.backyardnature.net/n/10/100516_4.jpg.
Whenever I arrive at a new place I make sure I befriend the folks in the kitchen! My good friend Josué is the gifted head cook at Hacienda Chichen and you can see him working hard handing out free food at http://www.backyardnature.net/n/10/100516_5.jpg.
It was a beautiful day. Good folks enjoying being together doing innocent things, lots of kids, a touching experience. And toward the end of the day it actually started looking like it might start raining again soon.
WHY DOES EXPERIENCING BEAUTY FEEL GOOD?
When I hear a Bach fugue, it feels good. The question is, why?
Sex feels good because our genes robustly predispose us to procreation. They've gone so far as to instruct our developing bodies to hotlink nerve-ending-rich sexual parts with our pleasure centers. Eating feels good because our genes installed hunger monitors in our bodies so we'd be tormented when our stomachs grow empty. This all makes sense. But, why do we feel pleasure just because tones in a Bach fugue are managed beautifully? It's hard to see how evolution could have encoded an appreciation of beauty into our genes, for how could that impart a competitive advantage to an evolving organism?
Maybe an answer is suggested by the Gaia concept -- the notion that planet Earth functions as a single self-regulating organism.
Those who think about the Gaia concept often suggest that humanity is such a threat to biosphere stability that Gaia identifies humans as disease organisms. Plagues and wars that reduce human numbers represent Gaia's immune system kicking in, trying to bring us under control. If there's something to that thought, we begin seeing how humanity's sense of beauty could serve to encourage Earth-friendly behavior in the human component of the Gaia unity.
Last week, for example, I remarked how beautiful it was seeing my Basil seedlings deploying their cotyledon solar collectors, harmonizing so perfectly with a basic principle for living sustainably on Earth. In the same vein, anyone living sustainably and harmonizing his or her lifestyle with Earth's natural systems senses the beauty in that lifestyle. People who have "found themselves" and are living according to their Earth-friendly beliefs invariably also recognize that to learn, and to empathize, and to share -- all features of dynamic systems evolving toward ever more sophisticated states -- are beautiful. And experiencing that beauty feels good.
So, maybe as wars and plagues can be thought of as Gaia's antibodies trying to bring the numbers of destructive humans under control, our feeling good doing beautiful, Earth-nurturing things can be thought of as Gaia's dopamine -- the human body's "pleasure hormone" -- encouraging Earth-nurturing humans to keep doing what they're doing.
Some people are born with highly developed esthetic sensibilities that unerringly direct them toward beautiful things, while in others that genetic imperative is less assertive. Even those born with acute esthetic sensitivities generally must make some kind of effort to activate and encourage their gifts. Those born with little esthetic sensitivity can be taught certain tricks that help them enjoy beauty, despite themselves. Such was my own case with music.
To sensitize oneself to music so that a Bach fugue gives maximum pleasure, usually one needs a little study and practice in such things as identifying themes and recognizing and reacting to changes in key. In the same way, to sensitize oneself to the beauties of Life on Earth, and thus to make oneself available to the pleasures Nature's beauty affords (via Gaia's dopamine), it pays to make an effort to learn about living things, how they work, how they interrelate, and to physically go places where Nature most exquisitely reveals Herself.
This effort-requiring sensitization process itself turns out to be a pleasurable undertaking. It's one of the few instances in life when the thing you have to do in order to feel good, itself feels good.
Best wishes to all Newsletter readers,