|
|
By Ben, on March 8th, 2010
Today’s word is a botanical term, hastula, which I assume originates from the Latin hasta, spear. I can only assume it because I don’t know it for a fact. None of my desk references, not Merriam-Webster’s Collegiate, not the “unabridged” American Heritage 4th edition, not even the venerable Oxford English Dictionary admit the term into the language. Even the online OED gives me this sad result:
 No results, alas, even in OED So, what to do now? Well, go back to the book in which the hard word arose. In this case, it’s Wunderlin and Hansen’s Guide to the Vascular Plants of Florida, 2nd edition. There, we see its use in botanical description of the leaves of Sabal palmetto, the cabbage palm:
Leaf blades triangular, held in a V with a downward curve, the costa extending fully or nearly the length of the undivided portion of the blade, the hastula acute to attenuate, the margin with long free fibers.
Ah-ha. Mm-hm. As I suspected. No help here. It’s got something to do with the leaves, or the leaf blades, but context really isn’t helping.
A quick Google search, though, turns up a nice definition from an article on invasive exotics in Hawai’i:
hastula In some palmate palm fronds, a flange of tough material on the upper side of the petiole where it joins the frond blade
That helps. So does this rather more technical definition from A Revised Classification of Fossil Palm and Palm-like Leaves, by Robert W. Read, Leo J. Hickey, which appeared in Taxon, Vol. 21, No. 1 (Feb., 1972), pp. 129-137:
A ligule-like structure (hastula) at the apex of the petiole (usually only on the adaxial surface, rarely on both surfaces) where the radiating segments are inserted on the palmate blade.
Now, if I only knew what a ligule was, I’d be in business. After all, if two respected scholars like Read and Hickey tell me that a hastula is ligule-like, well, that’s good enough for me! But here the editors of MW11e are kind to me, and explain that a ligule is
a scalelike projection esp. on a plant: as a: a thin appendage of a foliage leaf and esp. of the sheath of a blade of grass.
Whew. What a relief! Aren’t you glad to know that a hastula is like a scalelike projection on a plant? Sometimes learning about words can feel like you’re caught, like Eloise, on that gigantic traffic circle around the Arc de Triomphe:
And to come, ahem, full circle, i.e., return to the information about Sabal palmetto in Wunderlin and Hansen that I was looking up, it’s obvious that the shape of the scalelike projection known as a hastula can vary. In the cabbage palm, its form is “acute to attenuate.”
Geometrically, of course, an acute angle is one smaller than 90°. In nonmathematical terms, of course, acute means, “ending in a sharp point.” Botanically, I suppose, it means pretty much the same thing.
And here is what MW has to say about attenuate:
at·ten·u·ate \ə-ˈten-yə-wət, -yü-ət\ adj [ME attenuat, fr. L attenuatus, pp. of attenuare to make thin, fr. ad- + tenuis thin] (15c). tapering gradually usu. to a long slender point <~ leaves>
So the hastula of the cabbage palm is acute to attenuate, and looks something like this:
I think, given the photographic evidence, that I am justified in deducing that the word hastula has the same origin as hastate, which does indeed come from the Latin hasta, spear.
Below is another form the hastula can take, much more rounded. It’s from a different species of palm, one I have yet to identify:
And this final version of the hastula is even less spearlike than the last; it’s just a thin strip of plant tissue that separates the petiole/stalk from the palm leaflets/fingers:
So I’m not too solid on the derivation of the word, but my guess is that the first ones described were indeed spearlike, and the name stuck, even though, as the pictures above prove once again, etymology doesn’t dictate to nature.
In case you were wondering about that one-sidedness of the hastula that Read and Hickey discuss, well, here’s what it translates to in images:
See, no hastula on the adaxial side of the frond; if you want to see it, you have to turn it over and look at the abaxial part.
By Ben, on March 7th, 2010
By Ben, on March 4th, 2010
I’ve been reading Edward O. Wilson’s The Diversity of Life recently*, and was struck by some of his turns of phrase, and thought I’d share a couple of them with you. I’ve also been reading two of his three books co-authored with Bert Holldöbbler (Journey to the Ants and Superorganism), where the writing is much less dynamic. In this more personal book, though, Wilson writes lyrically and movingly about the “big picture” biology that so many of us need to remind ourselves about.
On mental puzzles that verge on obsession
Wilson opens the book with a vivid scene of walking through the rain forest at night, at leisure after a very long day; he is pondering new possibilities to explain the incredible profusion of life in the tropics, a weighty topic that he is extremely well suited to ponder (from Old French, ponderer, from Latin ponderāre, from pondus, ponder, weight). After all, he co-authored the theory of island biogeography, and had only been studying the natural world in the tropics for over forty years at the time! His thoughts kept returning to this idea, which he describes as
…the kind of favorite puzzle that keeps forcing its way back because its very intractability makes it perversely pleasant, like an overly familiar melody intruding into the relaxed mind because it loves you and will not leave you (5).
The puzzle Wilson is writing about is how to explain the existence of biological diversity rather than simpler systems dominated by one or a few organisms. In other words, why don’t dominant species dominate globally? Why would a successful organism not be able to succeed in every habitat without bothering to go through the process of speciation? Continue reading The Diversity of Life
By Ben, on March 1st, 2010
No, I’m not taking up drinking under the full moon (although that sounds like a nice idea!). I’ve got a new backyard astronomy project. Fresh off my foolhardy attempt to capture every day’s stage of the Winter moon (and having missed only two!), I’ve decided that now I’ll shoot for all the full moons of 2010, with the first full moon from December 2009 thrown in for good measure.
Above are the first three, the Blue Moon from 2009, and the Winter Moon and the Trapper’s Moon. For simplicity’s sake, I’m using the names from my iPod Touch app, MoonPhase; it’s not always right—it called December’s second full moon a Blue Moon, when in fact it was the Christmas Moon; it called the full moon from December 2 the Christmas Moon! For those who follow these things, the first day of Christmas is December 25; it doesn’t end until Epiphany in January. So the December 30 moon would have been the real Christmas moon, and the 3rd moon of the season, on December 2, should have been the blue one…
One of my goals in undertaking this project is to be able to see for myself how visible librations in latitude and longitude are throughout the year. For 2010’s moons so far, it looks like the Winter moon (Jan 30) has both the eastern and northern limbs tilted a little further away from us (Mare Crisium is a little closer to the limb) than the Trapper’s moon. (The “roll” in the two images is just due to incorrect alignment in Photoshop; I try to align the moon with the axes “true” but I invariably miss by a little bit. But that doesn’t affect the features near the limbs that are visible; only the actual difference in which exact face the moon is showing us affects that.)
Compared to the Blue Moon from December 1, 2009, the western limbs are very unfavorable. Look how much farther from the limb the Mare Humorum is in that first shot compared to either January or February.
For librations in longitude, then, the Mare Humorum in the west and Mare Crisium in the east form convenient signposts. For libration in latitude, the going is a little trickier, because both the northern and southern poles are hard to get your bearings on. But let’s not make things too difficult: just look at the most prominent crater at full moon: Tycho. That giant crater with its enormous ray system is a lot farther from the southern limb of the moon in December’s shot than in either January or February’s images. So December’s moon is showing us its southern side (the libration in latitude) and its western side (libration in longitude)
For the curious, here is a little table with the librations of the three moons. I took all the data from this website; the data on another useful iPhone app, Moon Atlas, appears to use a different convention to indicate direction of longitudinal libration, and I need to keep it simple, sister. Plus the app only displays libration in graphical form, so you have to interpolate the fractional values, which makes it a lot harder:
Moon Librations, 2009-2010
| Date |
Lat |
Long |
| 12/1/09 |
-5.25 |
-4 |
| 1/30/10 |
-3 |
+.25 |
| 2/28/10 |
5.4 |
+2.2 |
So negative values of latitudinal libration mean that the western limb is displayed (we see farther “around” to the west) and the eastern limb is “hidden”; negative values of longitude mean the northern limb is displayed, while positive values mean the southern limb appears favorably.
And, in case the pictures weren’t worth 1000 words, I’ll “translate” them for you: December’s blue moon had negative libration in latitude, so the western limb displayed to advantage, but positive libration in longitude, so the southern limb was also well viewed, while the northern limb was shy.
And so on for the Winter moon and Trapper’s moon.
By Ben, on February 26th, 2010
Psammophyte. This seems to be a fancy way of saying seaweed. Since this word is too hifalutin’ for the American Heritage or even Merriam-Webster teams to take on, here’s a definition of the term from Dawes and Mathieson (Seaweeds of Florida, U of Florida P 2008):
A plant that grows in unconsolidated sediments or on rocky subtrata that is impacted by sand scouring; these plants show specialized morphological and/or reproductive adaptations.
“Unconsolidated sediments” sounds to me like sand; not sure what else it could be (gravel or crushed shells, I suppose). And since psammo is Greek for sand, I’m going to say that it’s sand.
As far as seaweeds go, there are apparently all kinds of ways of classifying them. One is the various types of “attached macroalgae”: Psammophytic and lithophytic (lithos is rock) appear to be the binary categories here. The opposite of attached macroalgae would presumably be planktonic. As Dawes says, “most seaweeds are lithophytes that grow attached to hard substrata and form some of the most productive communities in the world” (17).
So what seaweeds are psammophytic? Well, to answer that question, I’d have to go back to the library, request an interlibrary loan, and reobtain my copy of Dawes and Mathieson. That sounds like a lot of work. What about a Google search?
Turns out that you don’t have to be a marine plant or algal growth to be a psammophyte. Any of those plants you see on sandy soil can be called psammophytic. So dune plants, like these lovely sea oats, would qualify:
 Sea oats (Uniola paniculata) Turns out it’s hard to see the sandy substrate in the shot above, so here’s a shot of a neighboring plant even closer to the water than that:
 Beachstar (Cyperus pedunculatus) And, just in case you need some color with your sand-loving plants, here’s a beautiful, and endangered, psammophyte of south Florida: Beach Peanut (Okenia hypogaea)
 Beach peanut (Okenia hypogaea) I saw all three of these psammophytes on a field trip with the Florida Master Naturalist program back in 2008. But I hadn’t known the hard word that describes them all until I ran across it in research on the seaweeds of Florida. Now I have a fairly long agenda of photos to take when I get to the beach again…
By Ben, on February 24th, 2010
People often wonder how they can help reduce their consumption of resources. Whether this question arises out of a laudable desire to help conserve our planet, or an equally laudable desire to help conserve one’s financial capital, the answer, at least sometimes, is to go native. This January, for example, we got a good lesson in the value of native plantings. The picture below is a non-native, but very pretty, flowering shrub in the genus Ixora.
Beautiful, isn’t it? Here’s a close-up of one of the flower clusters:
These flowers attract countless bees and other pollinators, who would probably be better off elsewhere, as Ixora doesn’t really have all that much in the way of nectar for them. It’s a showy cheat, is what it is. But these shrubs are not particularly long-lived, although this hedge on our front lawn has held on quite a bit longer than one might have expected: we’ve been in the house for 9 years, and it was old already when we moved in. Our neighbor, who has been here longer than we have, doesn’t remember our house ever not having these shrubs, so they’re at least 20 years old.
The prolonged cold spell we got this January, though, proved to be a bit hard for this tropical species to handle:
The leaves dropped all over the place, and it looked like the plant was ready to give up the ghost. And, rather than wait and see, I decided to help it along:
I’ve been itching to replace this exotic hedge almost ever since we moved in, and certainly since we redid the entire landscape in plants native to Palm Beach County, with a few exceptions that our landscape designer holds dear: Aristolochia gigantea, for the Polydamas Swallowtail caterpillars; the widespread Asclepias for the milkweed butterflies (Viceroys, Monarchs); and we left one or two of the “foundation” plants like the Areca palms by the entryway, and the Ixora hedge.
But now that hedge is history; soon to be replaced by, well, we know not what. Sabal minor? Coontie? Both? We want a hedge that won’t need clipping all the time, so its ultimate height should only be 4 or 5 feet. That reduces our options considerably. And we already have tons and tons of horizontal cocoplum, so I really don’t want to add more. Walter’s Viburnum would have been lovely, but it needs too much water for this high dry sand we’re on.
We also want a native plant, to provide food and shelter for butterflies and birds that evolved in conjunction with this ecosystem. Plus, the cocoplums and all the other natives did fine during the cold; the only casualties were this hedge in front, and a sister hedge in the back that looks like it might be on its last legs as well…
Stay tuned to see what the in-ixorable march of progress brings to Boca!
By Ben, on February 23rd, 2010
The waxing gibbous moon is at zenith (that is, directly overhead) in the early evening, so it’s a pretty conspicuous sight in the evening sky. Even on a rainy night here in south Florida, there are sometimes enough moments of clear skies to catch a glimpse or two:
I’ve been studying up on some of the techniques of nature photography in the blogs I’ve discovered on Nature Blog Network; one or two of them have to do with how to compose good landscapes with the moon.
I hope to be able to use some of the tips I’m learning to improve my decidedly amateur photography in the near future. But in order to do that, I have to get out into the field! Anybody want to sponsor a field trip?
By Ben, on February 22nd, 2010
There’s a line in an old Poi Dog Pondering song (“The Ancient Egyptians”) that always sticks with me; the singer, Frank Orrall, is explaining to his friends, who keep asking him why they can’t just take a bus or a car, the reason he prefers not to: “No, no, no, didn’t you know, you get to know things better when they go by slow…” Right on, Frank! In this anonymous world of air conditioning and motor cars it can be hard to get a good sense of just how the world around us works, and we need to be able to slow down from time to time to remain sane.
Well, I say we. I can only speak for myself, I suppose.
In this slow-things-down vein, our family unit went on a couple of walks this weekend, for the first time in a while. All three of us were present for Saturday morning’s stroll; this meant that when we saw something fun, we were able to snap a picture:
It’s amazing what you can see when you just take the time; things come right up to you. We always take as much time as we can just to look at things on these strolls. Well, as much time as Eric lets us:
He and his bus sometimes get impatient:
But even under the time constraints of an almost-two-year-old’s attention span, it’s possible to see things you haven’t noticed before. For instance, there’s a seagrape tree along our route; Saturday morning Mom was fascinated by the different colors of the leaves: some shiny green, some mottled with rust. It appeared that the newest leaves were shimmery red, then bright green as they got older, and then when they were really old (or just damaged by the cold snap in January?) they get “rusty”:
I’m not sure that’s how Coccoloba uvifera actually behave, here, but it’s something to keep in mind as we walk around, and to keep an eye on for future reference.
When we go on these strolls, we never go very far, and we never go very fast, but these walks aren’t about physical fitness. They’re more about renewing our connection with the neighborhood, trying to establish a sense of place in this all-too-anonymous world. Getting to know things better…
Sunday morning’s stroll was just the lad and me, and his buggy made three. We went around the familiar neighborhood, but without Mom, I couldn’t take pictures. And, of course, when you can’t do something, you really wish you could. For the first time in years, it seems, the Spot-breasted Oriole that lives down the street was in a fairly open tree, with the light just about right for photography. If only Mom had been with us, Dad might could have been able to get a picture. Oh, well.
And a little later on, I saw something I hadn’t seen before in the neighborhood: two hummingbirds, high in a flowering tree. They weren’t thrilled to be together; one of them chased the other one off with an angry buzz, but I was happy just to see the two of them, even though I didn’t have my binoculars and was unable to identify them to species. They’re rarer than I’d have thought here in la Florida, at least in my neck of the woods.
Take it easy!
By Ben, on February 19th, 2010
Here are two images of the Day Three moon, one from Wednesday night, and one from a month ago. Apart from the technical differences of exposure, and a slight misalignment (the “horns” of the moon aren’t exactly parallel, but that’s just an artifact of my inability to rotate them to the exact same angle, not a difference in the moon itself), what differences do you see? What’s responsible for them?
-
-
January 18, 2010, 6:48 p.m. EST
-
-
February 17, 2010, 7:34 p.m. EST
Tentative answers after the “read more” link…
Continue reading Different moons
By Ben, on February 18th, 2010
There aren’t very strong geologic, climatologic, zoologic or botanic parallels between my two “home” states of Florida and California. True, both states have endemic scrub-jay populations (the Santa Cruz island scrub-jay and the Florida scrub-jay), and many of the plants and animals of Florida’s “ancient islands” (scrub habitat) have western affinities, but beyond that, there’s not a whole lot linking the two places.
Oh, sure, there are some superficial parallels. I mean, when I was going to grad school at UCLA, I rode my bike through palm tree–lined streets, dodging expensive cars, with the sights and sounds of the ocean never too far away from consciousness. Here in south Florida, I ride my bike through, um, palm tree–lined streets, dodging expensive cars, and the sights and sounds of the ocean aren’t too far away. We moved away from California in part because the housing prices had become unaffordable. Now we’re in Florida where, it seems, housing prices had become unaffordable. In both places, it appears to have been a bubble.
Geographically they’re also superficially similar: Both are longer on the north–south axis than they are east–west. California covers close to 800 miles longitudinally and only around 250 in latitude, while Florida is around 450 miles N-S and surprisingly wide–360 miles from Pensacola to the Atlantic coast. Both of them also start out in the upper left and drift across the page to the lower right:
 
But Florida, surrounded by water on three sides, is only much more recently, and perhaps temporarily, emerged from the ocean. Only those ancient island systems like the Lake Wales ridge date back more than a few thousands of years. California, on the other hand, is millions of years dry.
The water offshore of the two states is remarkably different: the cold California Current keeps the Pacific waters quite chilly, even in summer; the warm Gulfstream, on the other hand, keeps our Florida waters comfortable, even in winter. And presumably, these differences account for a climatologic difference as well. As I’ve mentioned before, the clouds are different: in California, unless you’re in the middle of June gloom (which, as a recent study has indicated, may be fluctuating or even decreasing over time, causing potential problems for California’s signature redwood forests), the clouds are never that close to the ground.
But in Florida, it seems like they’re right smack overhead all the time:
Both states have some interesting herpetofauna. Below, a west coast treefrog, Pseudacris species, which by range I assume to be Sierran treefrog (P. sierra):
And here an east coast group of hylids, Hyla squirella (Squirrel treefrog):
And, since this is basically a backyard nature blog, here’s an introduced species, Osteopilus septentrionalis (Cuban treefrog), from my own (front) yard in Florida:
So, what does all this mean? Yes, two states on opposite sides of the country have clouds that may or may not be the same; flora and fauna that may or may not be the same; people and cities and coasts that may or may not be the same. One has a coldwater current close offshore; the other a warmwater one. So what?
Well, each state has a claim on my affections, and I’m going to make sure my family makes the most of each one:
|
|
