January 21, 2018
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A VINE-FORMING COWFOOT
Along the highway to Temozón, during my usual Sunday morning bike trip to buy fruit, dishpan-size splotches of something reddish-brown began showing up, conspicuous against the dark greenness of tree tops. I hadn't noticed that before, so I stopped for a look, and saw that the reddish-brown was provided by clusters of shiny, dangling fruits at the tips of vigorous woody vines, or lianas. The fruits looked like flattish, finger-length legumes of the Bean Family, as shown at https://www.backyardnature.net/n/18/180121bh.jpg
Closer up, the fuzzy fruits still looked like something out of the Bean Family, though they bore weird, green, flat-topped stigmas much larger than you'd expect, as seen at https://www.backyardnature.net/n/18/180121bk.jpg
Notice that the rusty-colored hairiness covers the goblet-shaped calyxes, too. I'd never seen this combination of features, though the liana's leaves looked just like those produced by species in the Bean Family genus Bauhinia, often called Cowfoots because of their shapes, as you can see at https://www.backyardnature.net/n/18/180121bn.jpg
But, the cowfoot species I know all are shrubs and trees, with white to pink or red flowers. And this liana's few remaining flowers after an earlier flowering peak were bright yellow, as you can see at https://www.backyardnature.net/n/18/180121bl.jpg
A broken-open blossom showed an ovary coated with dense rusty-colored hairs and that big stigma looking even more outlandish atop such a small ovary, surrounded by five stamens, as shown at https://www.backyardnature.net/n/18/180121bm.jpg
It took a while to identify this species, even though I felt sure of its Bean Family membership. But the Bean Family is enormous, with lots of genera I've never heard of. In the end, after slogging through all the genera known to exist in the Yucatan Peninsula, I was left only with genera I could recognize, but which I was almost sure this plant wasn't a member of. And then I remembered the cowfoot-shaped leaves, went to the genus Bauhinia and there it was -- a genuine yellow-flowered liana I'd overlooked until now.
It's BAUHINIA HERRERAE, with no English name other than the general name for species in the genus, cowfoot. In Spanish it's Pata de Vaca, which means, "cowfoot."
Happily there's a fine treatment of the cowfoot genus Bauhinia in the Yucatan Peninsula. It's a 2009 work by Rafael Torres-Colín and others in the Revista Mexicana de Biodiversidad vol. 80, #2. It can be freely downloaded in PDF format, found by searching on the title, "El génro Bauhinia (Fabaceae, Caesalpinioideae, Cercideae) en la península de Yucatán (México, Belice y Guatemala)"
This anomalous cowfoot species is fairly common in southern Mexico south to Nicaragua, and then again in Peru
The liana's slender, woody stems are strong enough for the Maya to use them to tie together beams in their hut roofs, plus traditionally it's been used medicinally to treat dysentery and hemorrhages. It's been reported used as a fish poison.
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ALDAMAS FLOWERING
Nowadays biking between the rancho and Ek Balam is a delight because of the superabundance of densely packed, yellow flowered Sunflower Goldeneyes forming walls along both sides of the road up to ten-ft-high (3m). Our page about Sunflower Goldeneyes with information and pictures is at https://www.backyardnature.net/yucatan/viguiera.htm
Often, down at the bottom of the Sunflower Goldeneyes there are groupings of plants with stems, leaves and flowering heads very similar to Sunflower Goldeneyes, but with flowering heads only about 1/3 the size, and bearing similarly smaller stems and leaves. Moreover, if you look at these smaller plants' flowering heads, you see anatomical differences, too. It's a different species, so easy to overlook in this roadside show staged overwhelmingly by Sunflower Goldeneyes. You can see a branch of this smaller but similar species at https://www.backyardnature.net/n/18/180121ad.jpg
Close-up, you begin seeing how this plant is different from Sunflower Goldeneyes, as shown at https://www.backyardnature.net/n/18/180121ae.jpg
Not only are this species' flower heads much smaller, but also they lack the Goldeneye's broad, golden eye. The eye is yellow, but with fewer disc flowers -- more correctly called "florets" -- with the disc florets' blackish anthers disrupting the "golden eye" pattern. Also, beneath the Goldeneye's head the bowl-like involucre involucre is composed of several series of overlapping green scales or bracts. This smaller species' bracts are arranged in only two or three series, as seen at https://www.backyardnature.net/n/18/180121af.jpg
The world of yellow-flowered members of the Composite/Daisy/Sunflower Family, the Asteraceae, is so vast that from the beginning the indentifier knows that one must "do the botany." It's essential to break open a flowering head and see what things look like inside. Our small species' open head is shown at https://www.backyardnature.net/n/18/180121ag.jpg
The three vertical items are disc florets with immature, white, bottle-shaped ovaries at the bottoms. The spectacular field mark to notice here is that each floret is nearly entirely wrapped around by and kind of bract called the palea, and the paleae are raspberry colored. Many kinds of yellow composite flowers don't produce paleae at all, and very seldom do raspberry colored paleae almost wrap around the floret ovaries. Also, atop the ovaries of composite florets you may or may not find a "pappus," which can come in many forms. Often the pappus, when present, consists of slender, white hairs, other times they form low crowns, or long or short spines. In this species, the pappus consists of a low crown of scales accompanied by short, broad-based spines called awns.
When this smaller species' flowers are pollinated, the yellow corollas of both disc and ray florets fall off, and when you break open one of these almost-matured heads, you see what's shown at https://www.backyardnature.net/n/18/180121ah.jpg
The large black item on the right is a cypsela-type fruit. The head's petal-like ray flowers are sterile, producing no cypselae, so this cypsela is the product of a disc floret.
All these details ultimately led us to ALDAMA DENTATA, native from central Mexico south through Central America to Venezuela. It bears no English name, but the genus name is pretty-sounding enough for us to simply call it Aldama. Though the literature suggests that the species is rarely seen here in the northern Yucatan Peninsula, in our area it's common. In much of its distribution area it's considered one of the most common weeds, especially where slash and burn agriculture is used. It grows at the weedy edge of my garden. In fact, wherever you see Sunflower Goldeneyes there's a chance to find Aldama, too, though you may need to pay close attention to distinguish them from runty Sunflower Goldeneyes.
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CIONOSICYOS VINE WITH FEMALE FLOWERS
Last month we looked at Cionosicyos excisus, a wild vine in the Squash/Pumpkin Cucumber Family. At that time I could find no female flowers. This week I came upon some females that weren't open yet. Of course I'd like to find some open ones, but it's hard. The immature flower, though, is interesting to see, its spherical inferior ovary fuzzily residing below slender, flaring sepals, as shown at https://www.backyardnature.net/n/18/180121ci.jpg
Leaves on this vine are variably shaped. Earlier we saw them deeply 3- and 5-lobed. This week's vine bore those, but also unlobed ones, as seen at https://www.backyardnature.net/n/18/180121ch.jpg
In that picture, notice the unopened female flower at the top.
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UPDATE: THE PINK-WATERED SALT PONDS OF LAS COLORADAS
This week I accompanied a family on a flamingo-viewing tour to Río Lagartos on the Yucatan's northern coast, getting to see old friends from my year of being there. The tourism scene at Río Lagartos has changed dramatically during the last two or three years. Now many more packaged tours find their way there in big tourist buses from Cancún and other eastern-coast, Caribbean destinations. Also, in Río Lagartos new hotels have sprung up, and sightseeing boats on the estuary seem to have doubled or maybe tripled.
My guide friends tell me that nowadays many visitors express less interest in watching flamingos than in seeing firsthand the pink waters of the big salt ponds a few kilometers east of Río Lagartos, at Las Coloradas. The water's pinkness is caused by algae containing unusually high levels of reddish pigments called carotenoids, especially beta-carotene. The main alga involved is Dunaliella salina, whose page, along with a picture of the pink waters, a salt pond, and mountains of piled-up salt beyond, is at our Dunaliella salina page, at https://www.backyardnature.net/mexnat/pink.htm
My guide friends think that the interest in seeing the pink salt ponds is fueled by social media -- people want to take selfies with pink water behind them, for Facebook.
Also among the guides you hear that at least in one pond -- the last pond in the chain of evaporation ponds and also the pinkest -- is made pink by the addition of chemicals used to encourage salt to crystallize quicker. Of course, when you hear that, you worry.
One of my friends learned that the chemical being used is potassium permanganate, KMn04. A quick check on Wikipedia's potassium permanganate page gave the reassuring information that this compound is so nontoxic that it's used medicinally for cleaning wounds and dermatitis. It's so important medicinally that it's on the World Health Organization's "Model List of Essential Medicines," a list of the most important medications needed in a basic health system. It's even used by municipalities in water treatment, mainly to remove iron and the rotten-egg smell of hydrogen sulfide from well water. Historically it was employed to disinfect drinking water.
The reason that potassium permanganate is used at Las Coloradas is that it causes salt to form more quickly in the evaporation pond or ponds. And, when it dissolves in water, it does indeed produce an intensely pink or purple solution. As far as I can tell, it's just coincidental that the pinkness of the untreated ponds with their carotenoid-producing Dunaliella salina alga and potassium permanganate's pinkness are so similar.
Potassium permanganate seems safe for humans. In water, potassium permanganate quickly transforms into non-toxic manganese dioxide, which precipitates out -- turns to gunk that settles to the bottom. It does have some effect on the environment, though. It kills phytoplankton, such as our carotenoid-producing Dunaliella salina, which similarly clots together and settles to the bottom. Also, it's slightly to moderately toxic to marine fish. This environmental-impact information is in a 2009 article called "Environmental aspects of drug and chemical use in aquaculture: An overview" by Hervé Le Bris and others, freely downloadable in PDF format.
The chemical reason potassium permanganate is of such versatile use is that it's a strong oxidizing agent, with an oxidation state of +7. That means that during the oxidation process seven electrons are lost. It's such an aggressive oxidizer that it was used in the flash powder of early photographers.
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LUCY'S REVOLUTION
I was showing Lucy and her partner around the garden. When asked what she did back home in southwestern England, she said, "I go from place to place teaching permaculture, making rich soil and helping gardeners get good harvests." She tends people's gardens for them and rehabilitates damaged soils; later I found that also, if she's asked, she'll also talk about the whys and hows of her veganism.
Lucy doesn't say much about her feelings for the land, plants and animals in her life unless it comes up naturally in conversation. In college she felt like her classes were largely irrelevant to the big problems she saw around her. She quit school, learned how to make gardens and live in a way she believed in.
Lucy's low-key manner isn't what you'd expect of a genuine revolutionary, but the sustainable-Earth option she's offering in my opinion is revolutionary. Revolutions cause big currents of historical events to quickly change course. If enough people took Lucy's advice, there'd be a tremendous revolution.
Since Life on Earth depends on such a revolution in human thought and behavior coming about soon, it's worth thinking about what historically successful revolutions were like.
One feature in common of all successful revolutions I can think of is that they've all had a theme that normally was expressed in a short but stirring slogan, such as "liberty, equality and fraternity," or merely "Throw the bums out!" And the most successful slogans are those supported by a simple, easily recognizable symbol, such as the swastika, the Cross, and the hammer and sickle. Why are slogans and symbols so necessary?
It's because they efficiently and effectively encourage people to work together on shared goals. If you try to convince masses of people to revolt, by talking sensibly to them, they start disagreeing on terms, concepts and procedures, and fall to arguing with one another. But, the human mind is configured so that if a pithy slogan -- even if the exact meaning of what the words mean is ambiguous -- is shouted often enough, with enough enthusiasm, verve and panache, and somehow associated on the subliminal level with time-tested feel-good causes such as loving the motherland, feeling brotherly to those sharing your racial and ethnic identities, and sharing your mythologies, most people tend to fall in line, no deep thinking needed.
But, in Lucy's revolution, what kind of slogan or symbol could possibly be successful? Something like "Up with permaculture and sustainability!" is too corny for anyone, but that's exactly what needs to be said. And what kind of symbol could ever grace Lucy's banner? A germinating bean, a singing bird, a bowl of granola topped with yogurt and strawberry slices? Imagine what Trump would say about such a banner, and how the voting millions would snicker.
So, Lucy's revolution probably won't get off the ground until a truly catastrophic environmental disaster comes along, something so obviously caused by inappropriate human thinking and behavior that anyone can see that a revolution is needed.
Still, I like to think of myself as being one of Lucy's co-revolutionaries, whatever slogan and symbol the movement eventually comes up with.
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Best wishes to all Newsletter readers,
Jim
