JIM CONRAD'S
NATURALIST NEWSLETTER
Issued from Hacienda Chichen Resort
adjoining Chichén Itzá Ruins in
YUCATÁN, MÉXICO

November 20, 2011

SALTATOR'S TEA
Around my hut on any given day probably you can see two species of saltator, the Black-headed and the Grayish. Howell in A Guide to The Birds of Mexico and Northern Central America calls saltators "fairly plain tropical grosbeaks of forest edge and second growth," and that fits our species, though their thick beaks aren't as massive as the North's grosbeaks.

In fact, I think of saltators as more like towhees. The other day I heard a Grayish Saltator calling with what almost sounded like an eastern North American Rufous-sided Towhee's DRINK-your-TEEEEEEEEEE. Howell describes it as choo-chi-choo or hi-whee chu weeeeh, but when I hear it I think of the towhee's tea. You can see a Grayish Saltator tea-calling at http://www.backyardnature.net/n/11/111120st.jpg.

The Black-headed is similar, except that its head is blacker and black fringes its white throat. You can see what I mean on our Black-headed Saltator page at http://www.backyardnature.net/mexnat/saltator.htm.

The Grayish Saltator is a common indicator species of the American humid tropics from Mexico to Peru and Brazil.

*****

PIGEON IN CHURCH
The terms pigeon and dove are used fairly interchangeably. However, in general, pigeons are usually thought of as larger, plumper birds, mainly in the genus Columba, while doves are smaller and more slender, often in the genus Zenaida. Pigeons and doves are different enough from other birds to have their own bird family, the Columbidae. The Yucatán hosts 13 to 15 species in the Pigeon and Dove Family, depending on how far south you think the Yucatan Peninsula goes. The farther south and east, the more species turn up.

During the last two years here at Hacienda Chichen I've grown accustomed to seeing White-tipped and White-winged Doves, as well as stubby little Ruddy Ground-Doves, but not much else, even though we're within the distribution areas of other species. While I was away, another species turned up, one shown at http://www.backyardnature.net/n/11/111120pi.jpg.

That picture is a little grainy and colorless because the bird is in dim light inside the storage room beside the old colonial church in which I lived when I first arrived here. The bird had entered an open door.

He's a Red-billed Pigeon, COLUMBA FLAVIROSTRIS. The bill is mostly whitish, being a little reddish toward its base. Red-bills are distinguished from other pigeons and doves in this area by the shoulders' rusty blushes. Other species either lack the rustiness or have rustiness spreading to other parts. If you're used to seeing only White-tipped and White-winged Doves, Red-bills stand out with their longer necks. Unlike White-tipped Doves they perch in treetops and unlike White-winged Doves often they perch alone.

It's interesting that several Red-bills have appeared here after being absent for at least a couple of years, and it's also interesting that about a month ago along the beach north of Mahahual the same species began turning up fairly commonly where I'd not seen it the previous five months. It's as if the species has invaded a large part of the Yucatán after being absent awhile, though my sample of two places is too small to come to such a conclusion.

Red-billed Pigeons are regarded as inhabiting lowland forests, forest edges and semiopen areas with forest patches and scattered trees from Mexico through Central America to central Costa Rica.

*****

LITTLE BELL MORNING-GLORY
It's the peak of morning-glory blossoming season now; weedy roadsides are riotously colorful with them, and there are so many species. We've already looked at eleven Yucatec species and it's easy to find new ones. For example, this week one turned up looking very much like North America's common, weedy, Ivy-leafed Morning-glory, but it was much smaller, as shown at http://www.backyardnature.net/n/11/111120ip.jpg.

A longitudinal section of a flower showing the blossom's different-length stamens and the style's spherical or "globular" stigma head, as well as bristly segmented hairs covering the calyx base, is at http://www.backyardnature.net/n/11/111120iq.jpg.

This is IPOMOEA TRILOBA, sometimes called Little Bell in English, though it has lots of names in many languages. This native of the Caribbean now is an invasive weed of roadsides and fields throughout the world's tropics. The flowers and leaves in the picture are smaller than usual, maybe because it was growing in such impoverished roadside dirt.

*****

POINSETTIAS FLOWERING
In the pleasant little Maya village of Xocempich, the first one-the-road settlement north of Pisté, a family's Poinsettia is beginning to flower, as shown at http://www.backyardnature.net/n/11/111120po.jpg.

A close-up of a flowering head -- just to convince you that it's a real Poinsettia -- gloriously unfurls at http://www.backyardnature.net/n/11/111120pp.jpg.

I write "flowering head" instead of flower because the last picture shows many flowers, not one. When we met this species, EUPHORBIA PULCHERRIMA, back in Chiapas in 2008, we examined its flower peculiarities, as seen at http://www.backyardnature.net/chiapas/poinsett.htm.

Of course the Poinsettia you may soon be buying as a potted plant for the Christmas season is much different from what's in these pictures. Since the first Poinsettias were introduced into the US in 1825, from Mexico, many cultivars have been developed.

Cultivars fall into two main groupings: One is a little- or none-branching one and the other branches freely. The main cultivar mass-produced nowadays is a freely branching one producing several flower heads per plant and retaining its leaves longer than others. In the mid 1990s it was discovered that the free branching actually was a symptom caused by a disease organism, a phytoplasma. Kill the phytoplasma and subsequently produced clones don't branch. A good history of Poinsettia production is available here.

The commercial Poinsettia, Euphorbia pulcherrima, is said to be native to southern Mexico and Central America, though I don't recall seeing it in the wild. Frequently, however, other species of the genus Euphorbia turn up with red bracts and/or Poinsettia-like flowering structure. Among such "Wild Poinsettias" we've seen Euphorbia cyathophora, shown at http://www.backyardnature.net/yucatan/poinsett.htm and Euphorbia heterophylla, on display at http://www.backyardnature.net/yucatan/wildpoin.htm.

*****

GRAPEFRUITS IN TREES
A pretty thing to see nowadays is big, round, yellowing grapefruits in dark green trees beside shady village homes. You can see a typical cluster at http://www.backyardnature.net/n/11/111120gf.jpg.

Grapefruits, like oranges and lemons, are citrus fruits, which means that they belong to the genus Citrus. You can see their typical citrus leaves with "winged petioles" causing the leaves look jointed at their bases -- orange and lemon leaves do the same -- at http://www.backyardnature.net/n/11/111120gg.jpg.

A sliced-open grapefruit off the tree whose leaves are shown, with thicker rind and more seeds than I'm used to in grapefruits bought in the US is shown at http://www.backyardnature.net/n/11/111120gh.jpg.

I'm wondering whether in that thick rind and numerous seeds there might be a story? For, the technical name for the Grapefruit tree is CITRUS x PARADISI, the "x" in the middle meaning that we're dealing with a hybrid. In other words, there's no "Wild Grapefruit" out in the wild from which today's grapefruit plants have been developed. The first grapefruits came into being in Barbados in the 1700s when an Orange plant, Citrus x sinensis, was crossed with a Pomelo, Citrus maxima, both species originally being from southern Asia, and Orange plants themselves being hybrids.

Pomelo (pom-EH-loh) fruits are very similar to grapefruits but much larger, their rinds are grossly thicker, and the wedge-shaped cells seen in cut-open fruits normally are more unevenly sized, causing the rind to be thicker above some cells than others. When I saw how thick-rinded, seedy and relatively dry-fleshed our grapefruit was, I wondered whether its parent tree might not have had more pomelo genes in it than most modern grapefruit trees do. Maybe grapefruit trees around homes in isolated little Maya villages derive from stock brought to the Yucatán by the Spanish during colonial times, before plant breeders produced cultivars with thinner rinds, fewer seeds and juicier flesh.

In fact, I'll bet that the Yucatán's little Maya villages are great places to find old strains of many cultivars, maybe strains going extinct out in the world as flashier ones take their place. And maybe sometimes the old strains have resistance to diseases or flavors or textures that newer ones don't.

While reviewing information on grapefruits I found that Wikipedia's grapefruit page not only has the usual praise of grapefruits and their juice as being especially nutritious and even medicinal, but also there's an interesting section on the grapefruit fruit's "drug interactions."

For, studies show that some compounds in grapefruit increase the effective potency of certain medicinal compounds, particularly those known as statins. This came to light when several deaths from overdoses occurred among people on medication who ate grapefruit -- grapefruit made their medicines too powerful. Grapefruit juice also can interfere with etoposide, a chemotherapy drug, some beta blocker drugs used to treat high blood pressure, and cyclosporine, taken by transplant patients to prevent rejection of their new organs. Grapefruit is powerful stuff! The Wikipedia page is at http://en.wikipedia.org/wiki/Grapefruit.

*****

GARDEN BALSAM FLOWERING
Most days I take an hour-long walk with Diana, a new receptionist at the Hacienda's welcome desk needing to improve her English. Sometimes we walk into the nearby village of Chan San Felipe, which is as Maya villagy as you can get. Beside one house's cinderblock wall grows the much branching, knee-high annual shown at http://www.backyardnature.net/n/11/111120im.jpg.

A view down a flower's throat showing that the corolla is "irregular" -- is bilaterally symmetrical -- is at http://www.backyardnature.net/n/11/111120io.jpg.

A side view of the same flower showing a feature distinctive of the group of plants we're dealing with is at http://www.backyardnature.net/n/11/111120in.jpg.

The distinctive feature is that one of the calyx's three sepals is much enlarged into a cuplike structure extending behind the flower into a long "honey-spur," which in the picture points toward the picture's top, right corner. Nectar is produced at the spur's base. On the cup's rim you can see a slender, greenish appendage directed backward. That's one of the calyx's two "regular sepals."

This is Garden Balsam, IMPATIENS BALSAMINA, and if you know your flowers you might remember that often members of the genus Impatiens are known as touch-me-nots because when their mature fruits are disturbed they explode, tossing their seeds far from the plant. I don't know if Garden Balsam fruits do that.

Garden Balsam, originally from India and Southeast Asia, has long been a garden favorite worldwide, and many cultivars of it have arisen. Red, pink, purple, and white flow colors are available, and there are double-flowered ones looking like camellia blossoms, and some with in-curving spurs. Despite such a variety of choices, today the species is losing ground to another "garden impatiens," Impatiens walleriana, which produces more flowers. Garden Balsam, though, as far as I'm concerned, has much more character, and is to be preferred.

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TWO FLOWER COLORS ON ONE BRANCH
My Tree Cotton is becoming an attraction, especially among the Maya employees who want seeds later so they can grow what their ancestors once grew. Foreign visitors also get a kick seeing how cotton can stand ten feet tall, plus do the marvelous thing shown at http://www.backyardnature.net/n/11/111120x2.jpg.

There you see a pale yellow flower and a rose-purple one arising near one another on the same branch.

Corollas emerging from their buds are pale yellow and they stay yellow as the blossoms remain receptive to pollinators. Once pollinated, flowers turn rose- purple, plus they close. By turning rose-purple, the flowers become darker and less attractive to pollinators, thus helping pollinators do their work more efficiently by not continuing to attract them to flowers already pollinated. Closing the blossom accomplishes the same thing.

Once a blossom has been rosy for a day or two it falls off in one piece, sometimes with an audible plop heard as I sit readying beside the bushes.

*****

ELEPHANT EARS FLOWERING
Next to the hut the Elephant Ears are flowering. You can see me standing beneath one of the plants at http://www.backyardnature.net/n/11/111120xp.jpg.

The 14-inch-tall "flower" (35cm) is shown at http://www.backyardnature.net/n/11/111120xn.jpg.

"Flower" is in quotation marks because Elephant Ears belong to the Arum or Jack-in-the-pulpit Family, the Araceae, so what we're seeing in the last picture is a white, fingerlike spike, or "spadix," bearing hundreds of flowers partially enveloped by a white, hoodlike "spathe." The visible part of the spadix bears male flowers. Notice that the spathe constricts near its midsection, enlarging and becoming green below. That part of the spathe loosely envelops the lower part of the spadix, which bears female flowers. Eventually the white, male parts will wither away while the lower green part will expand and the spathe will be filled with the remaining bottom of the spadix bearing numerous fruits -- like corn on a cob inside its husk.

Numerous species in several genera of the Arum Family are known as Elephant Ears. This one is XANTHOSOMA SAGITTIFOLIUM. Spikes and spadices of other species are similar but in small ways different. If only leaves are present, the species is known by its large size, its all-green color -- instead of having certain purplish parts -- and by how the leaf petioles attach to their blades in the particular way shown at http://www.backyardnature.net/n/11/111120xo.jpg.

In long-established plants, leaves arise from arm-thick, pale rhizomes that run atop the ground.

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MYSTERY PICTURE
At dawn I sat before the hut basking in the day's first sunbeams, vacantly gazing up at the enormous Elephant Ear leaf arching above me. I loved how the sun-drenched leaf, wet with dew, shined as with inner light, and how its raised veins cast dark shadows highlighting the veins' glow. Trying to capture the lush, fresh feeling of it all I took the photo at http://www.backyardnature.net/n/11/111120ee.jpg.

The picture falls far short of what I was trying far, but it does show something mysterious I hadn't noticed while taking the picture. In the vein shadows, what accounts for those slender streaks of light? It looks as if here and there the veins rise above the leaf surface letting sunlight pass beneath them. But that's not how veins work. Veins are sunken into a leaf's blade. Still, it looked so like the veins were rising above the leaf's surface that I went back to the plant to see what was going on.

It took awhile to figure it out. Can you do it? Here's the secret:

Each light streak is associated with a dewdrop suspended from the vein beside it. Each dewdrop bends the light and refocuses it, rather like a prism, shooting it into the shadow.

Neat, huh?

*****

MORNING-GLORY MORNING
Nowadays the Yucatán's weather is glorious. Mornings are chilly but it warms up fast, then the sunny afternoons are just hot enough for working up a sweat, but then there's a light breeze to cool you off. Last Sunday morning I biked up to Xocempich, the first on-the-road village north of Pisté. Along that narrow but paved road what most caught my eye were the morning- glory vines.

We have so many morning-glory species -- several of which I can't identify -- that sometimes I wonder whether ancient Chichén Itzá's Maya royalty might have created morning-glory gardens in which they developed cultivars not found elsewhere. Maybe now some of those cultivar genes flow through the wild stock expressing themselves in terms of unforeseen hues and unusual sizes and vigor.

Last Sunday, peddling down the morning-glory endowed road to Xocempich, I reflected on how different that morning's feeling was from Sunday mornings of the last six months, down on the coast north of Mahahual. There things felt so edgy. Always you sensed the ocean brooding beneath its calm, blue surface, always capable of turning violent at any time. The constant wind stung with salt spray, and out in the horizon-to-horizon mangroves crocodiles awaited, and mosquitoes; even the orchids were ten-ft-tall, remember?

But, last Sunday here in the peninsula's interior the landscape lay in self-satisfied, easy repose. A whole field of purple morning-glories yielded to a roadside of white ones with red ones intermingled, then there was an all-green forest edge with just a splash of pale morning-glory blue here and there. As I peddled along it was like passing through a long-playing symphonic pastorale graced with morning-glory motifs, sometimes teasing with brief, evanescent, four-part harmonies materializing before my very eyes as shown at http://www.backyardnature.net/n/11/111120m4.jpg.

So, last Sunday I thought about how people have a choice of where they live, and therefore of what the world is like to them, and what they themselves are like in response. You can be a whole different person just by changing your environment. And that thought led to the observation that most of us, despite such liberty, usually end up living pretty sedentary lives, seeing and being the same, year after year.

But then the next thought was that even staying in one place a human can change what he or she focuses on, and thus become a different person even without moving. We can spend our hours watching TV, or we can catalogue, learn about and empathize with flowers just outside the window beside the TV.

And then, at a higher level, without moving we can change ourselves in even more profound ways by choosing the world in which we root our spirituality. For example, we can interpret everything in the Universe as constituting a tricky test meant to determine whether our souls spend eternity in Heaven or Hell, or we can conceive of reality as evolving, beautiful-by-definition expressions of the Universal Creative Spirit's ever-more-gorgeous poetry. Just by flipping a little switch in the mind, all Creation changes its flavor.

How I should love to be a morning-glory vine twining up a sunflower's stem in golden sunlight. Imagine wind and butterflies all around, and my own precious scent wafting into the balmy air, for everyone.

And, what a thing that a bike ride down a morning-glory road on a Sunday morning brings about such thoughts. And, no wonder that so frequently my bike wanders off the road, even when nothing lies ahead but more open road and morning-glories.

*****

Best wishes to all Newsletter readers,

Jim