June 14, 2018
SILKY ANOLE ON THE PORCH
While I sat on the hut's porch reading, movement to my right caught my eye. It was the little whitish anole that often comes sits with me, looking around for unalert flies. I'd been assuming that my visitor was an especially pale form of the Brown Anole that had been so common in my hut back at Chichén Itzá, but then something unexpected happened, shown at https://www.backyardnature.net/n/18/180614an.jpg
That extended yellow dewlap with an orangish blotch was something I hadn't seen on Brown Anoles. A little delving into the matter turned up the information that such dewlaps might appear on a female Silky Anole, or maybe an immature male one. Silky Anoles sometimes are called Blue-spot Anoles, but the Reptile-Database web page for the species calls them Silkies, so I'll go with that. They are ANOLIS SERICEUS. The dewlaps on mature males may have conspicuous blue blotches in their centers
This species has been introduced to science under a remarkable number of names, so it's taxonomy has been a hard one to work out, and probably isn't settled yet. As the species is understood now, it's distributed from the central Mexican Gulf lowlands south through Central America into Costa Rica.
In Jonathan Campbell's Amphibians and Reptiles of Northern Guatemala, the Yucatán, and Belize I read that Anolis sericeus is abundant in many habitats, usually found on low bushes and shrubs, sitting vertically on tree trunks, or in leaf litter on the ground. Females deposit just one egg in several clutches established over the course of the rainy season.
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MYSTERIOUS FLOOD OF MERCURIAL SKIPPERS
Last Monday morning I went out to water the garden and was surprised to discover flitting about dozens of skipper-type butterflies I'd never seen before. Skippers are recognized by their plump bodies with broad heads, hooked antennae, and wings that are surprisingly small for such sturdy bodies. Skippers are fast fliers, and when most species land they quickly fold their stubby wings over their backs. Most skipper species are dark with white spots, and fairly similar to one another, as you can verify at the bottom of our Yucatan Butterfly Identification Page at https://www.backyardnature.net/yucatan/mariposa/
You can see that Monday morning's skippers were spectacularly different from those look-alike species, at https://www.backyardnature.net/n/18/180614sk.jpg
What a treat to meet a skipper with such a bright yellow head and back, and pale chest! That morning, they were sipping moisture from the manured soil I'd just watered, and one was so engrossed in his activity that a fine close-up of the head was possible, shown at https://www.backyardnature.net/n/18/180614sl.jpg
Of course these pictures went off to volunteer identifier Bea in Ontario, who in just a couple of hours got back with her ID: Here we have PROTEIDES MERCURIUS, the Mercurial Skipper, distributed from Argentina north through Central America to Mexico and the Caribbean Area, with strays sometimes turning up as far north as Florida, Louisiana and Texas. Its caterpillars feed on tree and vine members of the Bean Family, and the adults feed on flower nectar. The "Butterflies and Moths of North America" webpage for the species says that it's found near streams in lowland tropical forests, particularly in edges and openings, despite us having no streams in the northern Yucatan.
This sudden outbreak of Mercurial Skippers is something of a mystery. They feed on species of the Bean Family, which is the most commonly represented group of woody plants we have here, and their great distribution area suggests that the species is adaptable. So, why haven't I seen Mercurial Skippers in recent years? And why so many right now?
My guess is that in the past we didn't see them here in the interior except maybe around sinkholes with water in their bottoms, but nowadays papaya plantations are appearing in the neighborhood employing extensive irrigation systems that deliver water pumped from the aquifer, creating moist soil the species normally finds near streams. This time last year at the rancho we didn't have the big solar-powered water-pump we use now and didn't water as frequently, but now usually we have someplace the Mercurial Skippers' required moist soil.
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MEXICAN EBONY BEAN PRODUCTION
At https://www.backyardnature.net/mexnat/swartzia.htm we look at the handsome Mexican Ebony tree, which in mid May was loaded with orangish-yellow, legume-type fruits. Each Sunday on my bike trip to Temozón to buy fruit I've been checking on the same tree, hoping to catch the moment when its legumes split to release their beans. On June 3rd, the first pods were splitting, and I got to see at least one one bean, which was bright red, and seemingly covered with a soft flesh. Because the tree was inaccessible, I could only examine it via pictures taken with my modest telephoto lens. You can see the red bean of June 3rd, apparently having been pecked at by hungry birds, at https://www.backyardnature.net/n/18/180614_1.jpg
In that image you can see that a few pods already have expelled their beans, and turned black. I think the reason that on June 3rd I could see only one bean among hundreds of pods is that birds relished eating the beans as soon as they appeared. In fact, on June 3rd the tree was swarming with birds, mainly chachalacas, Black-throated Saltators and Altamira Orioles. I made many efforts to photograph a bird eating the bean, but the birds so nervously flitted about that they were too fast for me to focus on them. They were nervous not because of my presence, but because they were competing with other birds for a very few beans.
During my visit to the tree last Sunday, June 20th, I thought I'd see many more beans, and an even greater number of hungry birds. What I saw is shown at https://www.backyardnature.net/n/18/180614_2.jpg
During seven days all the legumes had lost their seeds, leaving only a few black, dried-out husks on the tree, and not a bird was present.
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HEAVY CROP OF CARIBBEAN GRAPES
At https://www.backyardnature.net/mexnat/vitis.htm we look at a stunted vine of Caribbean Grape -- a true grape vine, genus Vitis -- bearing only ten or so somewhat weather-beaten, end-of-rainy-season grapes. The vine had had a hard time producing even these, since it grew in deep shade in competition with many other vines, bushes and trees. This week I found a vine loaded with fully formed, healthy-looking grapes, as seen at https://www.backyardnature.net/n/18/180614vj.jpg
Those are immature grapes. A bunch of ripe ones is shown at https://www.backyardnature.net/n/18/180614vi.jpg
In that cluster, the bright red grapes are still too hard and bitter to taste good. The darker, purple or "grape-colored" ones are as sweet and tasty as you'd want, though compared to store-bought grapes their seeds were fairly large in relation to their flesh, as you can see at https://www.backyardnature.net/n/18/180614vm.jpg
Caribbean Grapes bear leaves typical of the genus, as shown at https://www.backyardnature.net/n/18/180614vk.jpg
The leaves' undersides are soft-hairy and silvery, as shown close-up at https://www.backyardnature.net/n/18/180614vl.jpg
Along the leaf's midrib crossing the image's center you can barely see among the taller pale hairs very short, honey-colored stalked glands.
Caribbean Grape vines are fairly common in the forest surrounding the rancho, but normally they grow in dense shade and don't produce much. After all my years in the Yucatan, this is my first encounter with a vine producing such a fine crop of grapes.
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TOBACCO FROG-EYE LEAF SPOT
In the garden I grow a few tobacco plants, not only to show visitors -- who seldom can identify these examples of one of the world's most famous plants -- and for making nicotine-based insecticide. Lately most of the plants have developed small, yellowish-to-white spots like those seen at https://www.backyardnature.net/n/18/180614tb.jpg
In that picture, the front leaves show new infections, while the leaf in the back with larger spots shows the disease at a more advanced stage. You can see that as the spots enlarge the leaf surface between spots yellows, and eventually the yellow areas die, turning brown and dry. A close-up of a leaf spot is at https://www.backyardnature.net/n/18/180614tc.jpg
Especially at the dead area's bottom boundary you can see a fringe of tiny, slender, brownish, hairlike items. That's fungal hyphae advancing into the tissue. In the spot's center, what looks like black lint is mature hyphae producing spore-producing stalks.
This fungal disease was easy to identify, first because there's plenty of information on the Internet about tobacco diseases, plus the disease commonly occurs in the tropics worldwide, as well as to a limited extent in the Temperate Zone.
In English the fungus often is known as Tobacco Frog-eye Leaf Spot. It's CERCOSPORA NICOTIANAE, the species name nicotianae referring to the Tobacco plant, Nicotiana tabacum. However, the fungus doesn't restrict itself to Tobacco, but rather also infects many other members of the Nightshade or Potato Family, such as tomato, eggplant, and weed species.
Spores are spread both through the air and in soil, maybe even by hitching rides on seeds of diseased plants. Despite the disease's common occurrence, it's not nearly as deadly as certain others. Infected leaves often are included during sales of the leaf, and end up in tobacco products. Diseased leaves produce what's considered a lower-quality tobacco smoke, because of the leaf's reduced alkaloid and sugar content, among other things, and an increase in nitrogen content.
Tropical air and soil are so full of Tobacco Frog-eye Leaf Spot spores that's very hard to protect plants from it. Two common-sense measures against it are to remove and burn contaminated leaves, and use trickle tape irrigation, because watering from above splashes spore-rich soil onto the leaves.
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JUNIPERS AT THE MOUNTAIN'S TOP
A little over two months ago, on April 5th, in the mountains east of Saltillo, Coahuila, northeastern Mexico, I started out hiking on a valley floor, and climbed a small limestone mountain that was grassy and scrubby at its base, but forested on top. At the top, at ±7000 feet in elevation (2100m), the forest was composed nearly entirely of widely spaced, low growing, somewhat gnarly pines and junipers. You can see one of the junipers, with a Mexican Pinyon Pine at the back, left, at https://www.backyardnature.net/n/18/180614ju.jpg
Mostly the junipers bore few or none of their berry-like cones, but on the tree in the picture two or three branches were thick with them, as shown at https://www.backyardnature.net/n/18/180614jv.jpg
By "berry-like cones" is meant that these are real cones, as to be expected among the gymnosperms. Technically, a cone is an elongated collection of flowers or fruits that are borne beneath scales, the scales attached to an axis. Among pines, the scales make woody cones, but among the junipers the scales are leathery and fuse together to create a cone that looks like a berry.
On some trees, branches were loaded with what's shown at https://www.backyardnature.net/n/18/180614jw.jpg
Junipers produce unisexual flowers, and these are cones of male flowers. Some of the cones' scales are pulling away from the cone revealing pollen-producing stamens below them.
Nine juniper species -- nine species of the genus Juniperus -- are listed for the state of Coahuila, and all of them produce scale-like leaves and berry-like cones somewhat similar to these, so I was worried about identifying these junipers to species level. However, when I pulled apart the tree's outer branches and saw what the trunk looked like, I thought the identification process might not be so hard after all. You can see what I saw at https://www.backyardnature.net/n/18/180614jx.jpg
First, I was surprised that in tree's interior hosted such a nice population of bromeliads -- probably because the outer branches created a more humid, protected environment inside. For identification purposes what's so helpful is seeing that this tree's trunks produce bark that peels off in long, slender strips. One commonly occurring juniper in northern Mexico is the Alligator-bark Juniper, with bark breaking into numerous small blocks, so obviously this isn't that species.
In fact, that unusual bark is exactly the kind on the super-abundant junipers we lived among on the Edwards Plateau up in Texas. Those were Ashe Junipers, called "Cedars" by the locals, and our Ashe Juniper page has lots of pictures and information about the controversial species at https://www.backyardnature.net/n/w/ashe-jun.htm
In fact, it turns out that our location atop that mountain in southeastern Coahuila state was exactly at the southernmost point of distribution of the Ashe Juniper, JUNIPERUS ASHEI, and these Mexican junipers were indeed that species. The cones' bluish color and silvery (glaucous) bloom also are important field marks.
I wouldn't have minded meeting a juniper species new to me, but it's also nice to meet this old friend at its southernmost home.
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HISTORY IS NATURAL
For reading on my Kindle I download books that can be acquired for free on the Internet, and there are many fine ones. My main source is Project Gutenberg, at http://www.gutenberg.org
There you won't find the newest Best Sellers, for Project Gutenberg offers only works that are free of copyright, so they're old works, mostly over a hundred years old. However, much of the greatest literature, many excellent autobiographies and treatments of history are now out of copyright, and they're free for the taking, in various reader formats.
I've been reading H.G. Wells' A Short History of the World, copyright 1922. It's a bit dated, but the broad sweep of recorded history is nicely presented. For example, it's good to be reminded how unusual the Sixth Century BC was, when so many great thinkers sprang up at the same time. Among the Greeks were Socrates, Plato and Aristotle. Also then, Isaiah was carrying Jewish prophecy to its sublimest, and in other parts of the world Gautama Buddha was teaching in India, and Confucius and Lao Tzu in China.
Taking the teachings altogether, it's striking that they share one point above all others: Their messages were simple, down-to-earth ones. For example, the Buddha taught that the key to happiness was to overcome one's desire. Aristotle taught us to be curious, and to think systematically and honestly.
It's important to me to notice that Nature also teaches in broad, simple strokes. She says, "Don't waste resources, and recycle what you do use," then She depends on us to work out the details. "Respect diversity," She insists, and then She deals with what happens if we don't. "Always strive for refinement, for understanding, for greater feeling and empathy," She asks of us, then lets those who don't refine, understand and feel be replaced -- eventually -- by those who do.
All these admonitions are clearly stated by Nature in terms of paradigms visible in Nature Herself. Our best example of that is how Life on Earth has evolved. If the biosphere is structured so that plants and animals don't waste resources, and recyclable resources are recycled, then humans should do the same.
That's because we're natural, too. We are not only enmeshed in Nature, but we are as much a part of it as any rock, star or butterfly, and natural laws apply to us just like everything else.
Once this sinks in, the next step is to realize that certain natural laws can be proven in test tubes, but others have to be confirmed by thinking or feeling. It seems to me that some of the greatest failed societies are those who may have respected some of the laws, such as those dealing with sustainable resource management and respect for diversity, but ignored the law made clear by the direction taken by evolving Life on Earth -- the law that's engendered ever-refining human mentality and feeling.
In fact, my impression from the History of the World is that more than any other natural law, the one we need to focus on right now is the one that's produced human mentality and feeling. If written out, maybe it would say, "In harmony with the general flow of evolution of Life on Earth, humans are meant -- both individually and socially -- always to strive for refinement, for understanding, and for ever greater feeling and empathy."
If we do that, the natural consequence is that a community's citizens feel a strong sense of solidarity with, and responsibility for, one another and Life on Earth in general, and are willing to make sacrifices now for evolving life of the future.
If we ignore that law, we're lost.
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Best wishes to all Newsletter readers,
Jim
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