January 3, 2010
SILHOUETTED BIRDS
The forest here is secondary, 25 years ago having been ranchland, cornfields, or very cut-over forest. Now forest is being left untouched around the ruins, gradually wildlife is returning, and in some places the forest already is tall and shadowy.
Often the most interesting bird species appearing in these shadowy areas just offer frustrating glimpses of themselves as they keep to heavy cover and dark shadows. That was the case the other day when three or four birds of a species I hadn't seen nearer Hacienda Chichen turned up in deep shadows, appearing as no more than silhouettes. I pointed my camera at them anyway, hoping for a lucky break. The best I could do is at https://www.backyardnature.net/n/10/100103wc.jpg.
Both the larger picture and the inset are grossly overexposed by PhotoShop in order to reveal features that otherwise would appear as pure, satiny blackness. Sometimes when the birds flitted through flecks of sunlight I could see that they were bright rusty, or reddish brown. The inset shows a yellowish bird but that's from the overexposure; it was really colored like the North's Brown Thrasher.
Note the tips of the tail feathers. Not many birds possess such sharp-pointed ones, and birds who do generally are those who forage a lot on vertical tree trunks, such as woodpeckers. But this was no woodpecker.
Best I can tell it's a Ruddy Woodcreeper, DENDROCINCLA HOMOCHROA, but I'm not betting my life on it. The beak doesn't look long enough, even though I've especially overexposed the head area so we can see how the beak extends well into the silhouette of the head, thus being longer than it looks. Ruddy Woodcreepers are not closely related to the North's Brown Creepers, though their tree-climbing behavior is very similar. They're also much larger than the 4-3/4-inch long (12 cm) Brown Creepers, being about 7-½ inches long (20 cm).
The three or four silhouette-birds were much involved with one another, churring constantly as they moved as a unit among shadows near the forest floor. The most notable part of their behavior, however, was how they quivered their wings like nestling robins begging worms from their parents. The bird in the picture appears to carry a straw so maybe here were several males trying to work a female into the right mood, as when several male gray squirrels follow a female all day until she's in the mood to mate with the dominant male.
If anyone out there has thoughts on all this I'd be glad to hear them.
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A SNAKE IDENTIFICATION CHALLENGE
At https://www.backyardnature.net/n/10/100103un.jpg you see a dead, 15-inch snake (38 cm) found along the road the other day when I walked to Pisté for fruit. I just can't figure it out, so maybe someone out there can.
It's one of several species we have mimicking the coral snake, or possibly it is indeed a coral snake. The coral species we have is the Variable Coral Snake, Micrurus diastema, so maybe this is one of the Variable Coral Snake's many variations.
I'm thinking it may be a snail-eater, genus Sibon, possibly the very variable Ringed Snail-eater, but on the Internet I just can't find pictures matching it.
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SCARLET SAGE'S AMAZING STAMENS
One of the most conspicuous wildflowers growing weedily along roads and at woods edges these days is the brilliantly crimson-blossomed Scarlet Sage, SALVIA COCCINEA, found throughout tropical America north into the southern US, from coast to coast. The Scarlet Sage bought by gardeners in the spring is a different species, a horticulturally modified plant based on a wild Brazilian Scarlet Sage, Salvia splendens. The sage used as a seasoning is Salvia officinalis. All three of these species are real sages, meaning that they're members of the genus Salvia, in the Mint Family. You can see Yucatan's Scarlet Sage at https://www.backyardnature.net/n/10/100103sv.jpg.
You know you have a sage -- a Salvia -- if the flowers bear only two pollen-producing stamens, the calyx (green part belowd the colored corolla) is topped by only two broad, liplike teeth (is "bilabiate"), the corolla's upper lip is entire or split in two, not 4-lobed, and the plant's leaves are deciduous. In all the sage blossoms I've seen, the flower's two stamens do something extraordinary. I've removed one side of a Salvia's corolla so you can see what I'm talking about at https://www.backyardnature.net/n/10/100103sw.jpg.
The long, slender, violet-tinged item forked at its tip is the style, which is the "neck" connecting the ovary down in the blossom with the stigmas up at the Y, where pollen germinates. So that' a female part.
With regard to the male part, the stamens of most kinds of flower are matchstick-shaped, the "stick" being the filament and the match head being the anther. The anther consists of two baglike parts, or "cells," which split open to release pollen. In the picture, the deep red, slender, slightly curved, horizontal item is a much modified anther. The two pollen-producing cells lie at opposite ends of the structure, most of the structure between them being "connective" doing no more than connecting the cells. The cell outside the corolla tube produces pollen but the cell inside the tube is sterile. The pale, slender thing attaching to the anther-structure's center is a more or less normal filament, its base attached to the corolla's side wall. Why do Salvia flowers go to such trouble producing such outlandish stamens?
First notice that the forked stigmas project beyond the other parts. Therefore, any hummingbird arriving at the flower bearing on his forehead pollen from another blossom will first touch that stigma with his forehead, thus pollinating the flower.
Now imagine the hummingbird's beak continuing to enter the corolla tube. As it enters it encounters two red, fingerlike things descending from the ceiling -- the inner arms of the two anthers. The arms yield, however, so the beak keeps going until it reaches the nectar, the anthers' inner arms being forced upward until they're flush with the ceiling.
As those inner arms ascend, the whole anther structure swivels at its attachment with the filament, and the outer arms -- the arms bearing pollen-producing anther cells -- arc downward... daubing the hummingbird's forehead with pollen. So that's how pollen from another Salvia flower got on the hummingbird's forehead in the first place.
If you grow sage, or Salvias, you can see this on your own flowers. It's amazing, but it's something happening around us all the time.
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BUTTERFLY PEA
Wildflower fanciers in the southeastern US will be familiar with the Butterfly Pea, Centrosema virginianum, a slender, vining member of the Bean Family with large, pinkish flowers. Ever since I got here, along weedy woodland trails and roadsides a different species of Butterfly Pea -- a different species of Centrosema -- has been flowering, as shown at https://www.backyardnature.net/n/10/100103ct.jpg.
That's CENTROSEMA SCHOTTII, fairly commonly distributed from southern Mexico through Central America to Ecuador and Brazil. Several Butterfly Peas occur in the Yucatan. C. schottii is distinguished from the others by its leaves' three leaflets abruptly broadening at their bases.
The blossoms of all Butterfly Pea species do something remarkable: They twist 180° on their pedicels so that the flower as we see it is upside-down relative to other Bean-Family flowers. If you need a refresher on how Bean-Family flowers have five petals consisting of the broad, top "standard", two "wings" on each side, and two lower petals fused together to form a boat- shaped "keel," I've diagrammed it all at https://www.backyardnature.net/fl_beans.htm.
In Butterfly Pea flowers the "standard," which usually rises above the flower, has become a broad platform spreading below the rest of the flower. You can get a better look at this peculiar configuration at https://www.backyardnature.net/n/10/100103cu.jpg.
In that picture the curving item at the top, left is the "keel," which usually lies at a bean-flower's bottom. The two side "wings" are where they should be, just oddly shaped. The blossom is over an inch long (3 cm) and will give rise to a slender, stiffly straight legume about six inches long (15 cm). In the Yucatan the flowering season lasts through most of the dry season, from October to March.
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ELEPHANT EARS
As I work on Hacienda Chichen's "Plant Finding Guide" often it's a challenge to identify the plants. For example, take the case of the Elephant Ears shown at https://www.backyardnature.net/n/10/100103ee.jpg.
It's obviously what everyone up North calls Elephant Ears, but that's not saying much because members of the genera Alocasia, Colocasia, Anthurium, Caladium, Philodendron, Monstera, and Xanthosoma all are sometimes called "Elephant Ears," and often within those genera several species also share the name. Any plant with large, arrowhead-shaped leaves is likely to be called Elephant Ears. All the various Elephant Ears' leaves look pretty much the same, so usually you need the flowers for identification. Happily, the plant in the picture is flowering, as shown at https://www.backyardnature.net/n/10/100103ef.jpg.
The upright, white item is a spike or spadix covered with tiny flowers and the horizontal white thing is a leafy sheath or spathe. Also note the purplish "fruits" below the spadix and sheath. With so many botanical details available you'd think that IDing the plant would be simple.
One problem is that on the Internet, which here is my main source for identification, many pictures are labeled with contradictory names. Another problem is that among the ornamentals there are many cultivars whose traits overlap one another.
Having said all that, I'm calling what's in the picture ALOCASIA MACRORRHIZA 'BLACK STEM', the "'Black Stem'" indicating that it's a special cultivar by that name. To browse a page showing several Alocasia macrorrhiza cultivars, with 'Black Stem' among them, visit http://www.agristarts.com/alocasia_main.htm.
A picture showing 'Black Stem's' black stems, with another Elephant Ear cultivar in the background that is larger and with regular green stems is at https://www.backyardnature.net/n/10/100103eg.jpg.
The 'Black Stem' cultivar is a smaller, more shade- tolerant form of the wild species, the "Giant Taro" of the Pacific islands and eastern Australian rainforests. The wild form, which can reach 15 feet (4.5 m) and taller has underground parts that are edible if cooked for a long time.
While I was below the plant photographing the flowers I looked up and saw something very pretty. It's at https://www.backyardnature.net/n/10/100103eh.jpg.
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FISHTAIL SWORDFERN
Can you figure out what you're seeing at https://www.backyardnature.net/n/10/100103fi.jpg?
The picture shows two pinnae of a fern frond, a pinna being the frond's primary or "final" division. It's like the smallest division of a compound leaf. The dots along the margins are sori, which are clusters of tiny, baglike sporangia filled with spores. We've seen lots of frond pinnae with sori during our wanderings but none like this. These pinnae are remarkable because they're forked and then the fork branches fork again.
One name this fern goes by is Fishtail Swordfern. It's NEPHROLEPIS FALCATA. Its exact origin is unknown but some experts suppose that it's a mutant cultivar that arose from the Giant Swordfern, Nephrolepis biserrata, which grows wild in the tropics worldwide and is much planted. The Fishtail mutant occurs only under cultivation and where it's escaped locally from cultivation.
A close-up of three old sori along the margin is at https://www.backyardnature.net/n/10/100103fj.jpg.
It's clear that these are old because the baglike sporangia already have split open, released their spores and themselves have fallen off, leaving only sporangia stumps. The picture is worth seeing, however, because it shows the unusual way the cellophane-like sori covering, the indusium, arises all around each sorus, like a ruffled placemat beneath a pile of grapes. Usually indusia, if present at all, arise along one side of a sorus, not like a bowl beneath it like this.
Fishtail Swordfern is planted in tropical gardens worldwide. It's a big, robust fern that hangs gracefully. If given enough sunlight and water its fronds reach four feet long (120 cm).
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THE "RED FUNGUS"
It being the early dry season here, not many fungi are conspicuous. However, among the few species who do catch the eye is the small, tough-leathery shelf fungus with a red cap and growing on wood shown at https://www.backyardnature.net/n/10/100103py.jpg.
Notice how the fruiting body on the right has simply grown around a dry leaf that was in its way as it expanded. The fungi in the picture are about 1-½ inch across (4 cm).
Without having a microscope, the best I can determine is that this is probably PYCNOPORUS SANGUINEUS, described on one Internet page as a "poisonous pan- tropical white-rot fungus that recycles lignin." "Pan-tropical" means "found in the tropics worldwide." Several species are very similar, but its small size, commonness and its many-pored undersurface all suggest this species. Its undersurface and stem are shown at https://www.backyardnature.net/n/10/100103pz.jpg.
Herbs that are poisonous in one context often turn out to be of medicinal value in other contexts, and that seems to be the case with poisonous Pycnoporus sanguineus. Derivatives of this fungus serve as antibiotics against many of the most important pathogens by inhibiting specific metabolic pathways. Also they are used to absorb certain heavy metals in the blood stream.
The fungus's role in Nature of breaking down lignin apparently can be transferred to the bioremediation service of breaking down crude oils at oil-spills.
The species also occurs in Florida in the US.
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SOUTHERN CROSS
You may be surprised to learn that from atop the little hill where I stay, when I go out to jog before the sun comes up each day, I can clearly see the constellation known as the Southern Cross, or Crux Australis, hanging right above the horizon exactly to the south.
We're 20 degrees north of the Equator here, at about N20°40', so how come I can see the Southern Cross, which we think of as marking the spot around which all the rest of the southern sky rotates, at 90°00' south of the celestial equator? Also you may be surprised that after looking at the Southern Cross I can turn around and very clearly see the North Star, Polaris, suspended above the northern horizon about a hand's width high if the hand is held at arm's length.
The secret to this riddle is that, while Polaris does lie pretty close to the north celestial pole at 90°00' (Polaris is at 89°18'), the Southern Cross stands a good 20° away from the south celestial pole. In fact, the South 60° line runs right through the constellation.
One thing that this means is that the Southern Cross isn't nearly as precise as a direction giver as the North Star. It also means that six months from now the Southern Cross will be visible from here around dusk but not at dawn. If I'm here jogging at dawn next June, the Southern Cross will lie way below the horizon.
If I can see the Southern Cross from the Yucatan, can people in the US see it? From Miami theoretically the Southern Cross's four stars lie above the horizon. However, any clouds or haze on the distant horizon would obscure the constellation, or at least its lower stars. As far north as Atlanta, Georgia, however, already the Cross lies completely below the horizon.
Here's how I locate the Southern Cross here. First I find the Big Dipper, Ursa Major. Letting Ursa Major's handle point across the sky I look for a bright star about 1 hand-width and three finger-widths away. That bright star is Arcturus in the constellation Boötes. Keep following the line in the same direction for another one-hand-and-three-finger-widths and you come to a similarly bright star, which is Spica in the constellation Virgo. (Remember that from the Big Dipper's handle tip you "Arc to Arcturus, then spike to Spica... "). Continue on the same trajectory but this time for about two hand-widths, almost to the horizon, but jag maybe half a hand-width to the left.
There you see four stars right above the horizon, the one on the far right not as bright as the others, and those stars are arrayed like the four points of a kite, or a cross without a center spot. That's the Southern Cross.
On my computer I have an old freeware sky-observation program called SpaceExplorer. It generates star and planet charts for any date, time and place. The screen showing the Southern Cross, labeled Crux Australis at the center bottom, as seen here at 5 AM on January 1, is at https://www.backyardnature.net/n/10/100103sk.gif.
In that picture the green, curved line indicates my horizon, so you can see how far above the horizon the Southern Cross is when seen from here. In the US and Europe you should be able to see Leo and Virgo at dawn. The red dot in Leo is Mars and the yellow symbol in Virgo is Saturn.
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NATURE JAZZ
This week Christopher at the University of the West Indies in Trinidad & Tobago emailed asking about my first book, On the Road to Tetlama, published in 1991 by Walker and Company of New York. He was writing about "nature writers" and basically wanted to know what was on my mind when I did that book. The book described several months I spent in and around the wooded, steep, muddy, slummy slopes of Tamazunchale, San Luis Potosí, Mexico, befriended by a poor family of indigenous Nahuatl origin. He said that reading between the lines he could figure out that I was running away from something, but that there seemed to be more going on that he couldn't put his finger on.
I had to think awhile for an answer because those days seem like a life that happened to another person, back before my Germany and Belgium years, before my hermit years in Mississippi, back when I still felt like an exiled Kentucky farmboy. But, finally I remembered.
"Think jazz," I told Christopher. In the spirit of John Coltrane I wanted to put myself in a whole new world and improvise day by day, the theme being me interacting with Nature and the good people around me. Not really any point to it, just things happening and me feeling poetic about it, and sharing my feelings.
What did this have to do with "nature writing"? I think Christopher understood, for I could tell he was a smart, perceptive man and at the end of his last letter he appended this line, without further comment:
"It don't mean a thing if it ain't got that swing."
That's both the name of a 1931 jazz composition by Duke Ellington with lyrics by Irving Mills, and a profound statement. It explains why a naturalist might approach Nature with a jazzy head.
For, when you look at how Nature has been composed, with Giraffes and Gingkoes and viruses all interrelating as they coevolve, and all the kinky quantum-mechanics stuff going on at the subatomic level, and the Universe's expansion actually speeding up, and all those other possible dimensions with parallel realities, and even 96% of our own Universe being undetectable "dark matter"... anyone with a feeling for jazz recognizes that that's jazz. The Creator jazzing, with a touch -- if you think about it -- of the blues.
If the Creator jazzes, and I'm into harmonizing with the general flow of the Universal theme, am I not to jazz, too, in everything I do?
For years I kept that thought in mind all the time, but then maybe I got distracted here and there, making birdlists and web pages and so, until now I'd almost forgotten it. But now Christopher has reminded me, reminded me to keep jazzing day by day, for:
"It don't mean a thing if it ain't got that swing."
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Best wishes to all Newsletter readers,
Jim
