The stone centipede

In late March I went to the Lakeshore Preserve, on a quest for spring ephemerals. Despite the warm air, the trails still had a layer of snow on them, and though new shoots were poking their way up through the leaf-litter, nothing was in bloom and little living was to be seen out in the open.

But in the shelter of fallen and decaying trees there were definitely signs of activity. In particular, curled on the underside of a loose sheet of bark propped against a log was this splendid – and very calm – stone centipede (order Lithobiomorpha, class Chilopoda – the centipedes – and sub-phylum Myriapoda, the centipedes and millipedes):
Stone centipede, Lakeshore Preserve

The order takes its name from the genus Lithobius, a classification due to William Elford Leach, FRS, assistant keeper of the British Museum’s natural history department in the early 19th century. Leach’s Wikipedia biography states delicately “Leach’s nomenclature was a little eccentric”. The linked article gives a little more detail:

A Leach legend arose about a beloved Caroline (wife, sister, or friend?) who was immortalized in the mostly acronymic isopod genera Anilocra, Canolira, Cirolana, Conilera, Nelocira, Nerocila, Olencira, and Rocinela.

In the first episode of the rebooted Cosmos, you may recall seeing Tiktaalik, the renowned intermediate between fish and tetrapods, crawling up out of the surf at Neil deGrasse Tyson’s feet. Another scientific Neil – Neil Shubin – led the team that found Tiktaalik after several arduous expeditions to Ellesmere Island in the Canadian Arctic; the Inuktitut name pays a courtesy to the team’s Inuit hosts. As it happens, this Neil can also be seen on television, in a three-part adaptation of his book Your Inner Fish, on PBS; and you can stream it, if like me you don’t have actual television. As with Cosmos, by the bye, I can’t guarantee that the network is going to leave those streamable episodes up, so, apologies if you arrive here and they’re already gone. It’s great stuff, though, so if that’s the case I’d still urge you to seek out a DVD or find it on Netflix or Amazon or wherever it happens to land.

Tiktaalik is pretty ancient; but when that first Tiktaalik stuck its head out of shallow water to have a look at the land, it might well have seen a myriapod already quite at home. By that time, myriapods had already been on the land for some fifty million years; nearly as much time as separates us from the end of the dinosaurs. In fact, the oldest known fossil of a land animal is a myriapod, found in Scotland ten years ago by bus driver and amateur palaeontologist Mike Newman.

They’ve lived on the land through all but one of the great extinctions, without needing to change too radically in form or habits of life. That’s worth taking your hat off to.

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I heard the spring wind whisper

The spring equinox has come and gone, but it is still wintry – the temperature barely crept above freezing today, though it felt warmer in the sun. Piles of dirty snow are still lurking everywhere, and ice still festoons some tree-branches together with signs of life:
Ice and new growth, Starkweather Creek
Underneath the stones, a thin layer of ice still sits on top of the soil, but woodlice, beetles, and little spiders are venturing out upon it:
Wood-louse, Starkweather Creek
Beetle, Starkweather Creek
And best of all, new leaves are coming up through the leaf-litter:
Leaf, Starkweather Creek
There will be violets within a few weeks. Time to go farther afield and look for spring ephemerals!

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Darwin’s Day

Here I first saw a tropical forest in all its sublime grandeur — nothing but the reality can give any idea how wonderful, how magnificent the scene is. If I was to specify any one thing I should give the pre-eminence to the host of parasitical plants. Your engraving is exactly true, but underrates rather than exaggerates the luxuriance. I never experienced such intense delight. I formerly admired Humboldt, I now almost adore him; he alone gives any notion of the feelings which are raised in the mind on first entering the Tropics.
-letter from Charles Darwin to John Stevens Henslow, 1832

My mother recently sent me a newspaper clipping with a picture of a blue Morpho butterfly, which vividly called to mind my own first sight of a tropical forest, in Monteverde, Costa Rica; before even leaving the property I was staying on I saw a large, iridescent blue Morpho dart out and then fly far away before I even had my camera turned on. An incredible sight. And then, a few steps further on, at my feet marched a column of leafcutter ants, their leaf-fragments bobbing as they walked. I must have watched them for a good half hour.

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Snowstorms on January the twelfth

A great sleepiness came over Frodo; he felt himself sinking fast into a warm and hazy dream. He thought a fire was heating his toes, and out of the shadows on the other side of the hearth he heard Bilbo’s voice speaking. I don’t think much of your diary, he said. Snowstorms on January the twelfth: there was no need to come back to report that!

But I wanted rest and sleep, Bilbo, Frodo answered with an effort…

-Tolkien, The Lord of the Rings, Book II

We are enjoying good conditions here in southeastern Wisconsin for the Aurora Borealis, but we are also “enjoying” pretty extensive cloud cover, so… nothing to report on that front. There has intermittently been some decent stargazing, with a very bright Jupiter and the Great Orion Nebula to be seen. The cloud cover came with a dramatic increase in temperature, leading to rainfall that instantly became sheets of treacherous ice covering the sidewalk.

Speaking of ice, I’ve been enjoying the reports from the 2013 Australasian Antarctic Expedition by the BBC World Service podcast Discovery; yes, the one that got stuck and had to be helicoptered out. The expedition started on the hundredth anniversary of another Australasian Antarctic Expedition, led by Douglas Mawson. His account, The Home of the Blizzard, is available from Project Gutenberg; in it you will find the hair-raising narrative of how Mawson, sole survivor of a disastrous trek, had to claw his way out of a crevasse while all his skin was coming off due to hypervitaminosis A and make his way back to the expedition’s base just to see the ship departing for New Zealand for the winter, and then spend an Antarctic winter in a tiny cabin with several other people. Who not only did not kill or maim one another, but got on fine, diverting themselves with cooking, printing a newspaper, and high-stakes gambling for chocolate.

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“Lost isn’t always a bad thing”

Baby snapping turtle (Chelydra serpentina), UW Arboretum

Governor Nelson State Park, WI

This world is wild as an old wives’ tale,
And strange the plain things are,
The earth is enough and the air is enough
For our wonder and our war…
-G.K. Chesterton, “The House of Christmas”

"Lost isn't always a bad thing", Lakeshore Preserve, UW-Madison, 10/6/13

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Where his sea of flowers began

The Westport Drumlin Natural Area is a tiny remnant of the Empire Prairie which – true to its name – once covered a large swath of Dane and Columbia Counties in southern Wisconsin. It also went by the more prosaic name of the Arlington Prairie. To get there from Madison, you ride northward out of town; in fact, the transition from urban to rural in this direction is amazingly abrupt, and in the blink of an eye you pass from subdivisions and Skipper Bud’s boat store to farmhouses and to fields luminous and pastel-coloured in early morning summer sunlight:
Early morning, River Road, Westport, WI
and you meander up and down along River Road, then finally turn off to climb the steep bank of the drumlin itself. The view from the top of the drumlin compensates for the effort of the climb:
View from Westport Drumlin
Wandering through the Area itself was actually somewhat humbling, because my untrained eye wasn’t really able to tell this relict prairie from the restored ones that are much more common. At times, evidently, there are guided walks, and someday I must show up for one. I did see a very attractive little grasshopper:
Grasshopper, Westport Drumlin
but didn’t see Westport Drumlin’s most interesting insect resident: the red-tailed prairie leafhopper, Aflexia rubranura. If you follow the link you’ll see that it’s not the most spectacular sight in the world, but it’s still pretty interesting; in large part because it sheds light on the history of the landscape. And not only on the landscape I’m living in now, but the one that I grew up in.

Both of which are connected by something I hadn’t heard of before starting to write this post – the prairie peninsula. Most of the North American prairie lies on the Great Plains, west of the Mississippi – at the hundredth meridian, as the song goes. However, there’s a sizable piece of it that pushes eastward, through southern Wisconsin, Illinois, Kentucky, Michigan, and Ohio, which have increasingly infrequent patches of remnant prairie, even to southwestern Ontario. This piece was called the “prairie peninsula” by Ohio biologist Edgar Transeau. Now, if you find a fragment of tallgrass prairie within the city limits of Windsor, Ontario, you may (a) be as surprised to learn it as I was, despite having grown up only a couple of hours away, and (b) ask the natural question of how it got to be there. Did it come into existence independently, due to changes in the local climate and migrations, or did much more prairie once come a lot farther to the east than it does now?

So it seems like the evidence points, in some though not all cases, to the latter answer, and a good part of that evidence is due to that nondescript little leafhopper and its relations. The story’s not simple; not even completely settled. It seems fairly certain that between 9,000 and 5,000 years ago there was an episode called variously the Xerothermic, the Hypsithermal, or the Holocene Climate Optimum, when summer temperatures in North America were some 1-2C higher, enough to make the area around the Great Lakes dry enough to favour prairie over forest. There may have, also, been episodes during the last Ice Age that favoured prairies to the east – and during one of those periods, Aflexia rubranura may have made its way to Manitoulin Island in Lake Huron, another place it can still be found. (Another Ohio biologist, E. Lucy Braun, thought there must have an another period of eastward prairie expansion before the last glacial period, so, more than 85,000 years ago. I don’t know what the current thinking on this idea is.) The leafhopper way of life makes it unusual for them to get picked up and carried long distances by winds, so if they’re found someplace, chances are they arrived there the slow way, following their food from point A to point B. Since as a rule they only eat one or a few kinds of plant, communities containing that plaint – prairie dropseed, in the case of Aflexia – must have existed all along the route at some point in time.

The prairie is so congenial to leafhoppers, in fact, that they have evolved whole new genera in it; there are more than 600 species of leafhopper which exist only within the North American prairie. I don’t know that this approaches the diversity of form and habitat of, say, the cichlids of Lake Victoria; but it seems very rich for the temperate zone. Despite their shy and retiring nature, though, there are some vivid-looking leafhoppers, such as this Graphocephala coccinea:
Candy-striped leafhopper
… which is not, in fact, endemic to the prairie, but can be seen even in urban neighbourhoods, as this one was.

In sum, though, the difference between what I could see and what was there to be seen is a reminder that, as far as nature goes, I’ve maybe progressed from looking at the pretty pictures to being able to tell (some of the time) what the illuminated letter at the top of the page is. That’s still a long way from reading the text.

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Demon-haunted worlds

“No equations! It’s after dinner.”

So Jim Crutchfield promised. He was as good as his word, too: for the duration of a lecture that spanned an hour plus, there was not a single equation or table of data to be seen.

The talk was one of the Center for Complexity and Collective Computation’s ongoing series of John von Neumann Public Lectures. No equations or charts, but there were plenty of interesting ideas. I scribbled like whoa to remember even a handful. Before dinner, even getting that many down would probably have been impossible.

The central part of his exposition was, puckishly, taken from a Honda commercial. If you don’t feel like watching the video, it shows a disarticulated Honda Accord, put together to form a elaborate Rube Goldberg/Heath Robinson (your pick) contraption whose execution takes up the whole 2 minutes. He apologized for the product placement, and then gave his team’s back-of-the-envelope calculation of how much energy of the initial impetus to the system was remaining by the time it reached its end: a mind-boggling 10-60 of it. So, he concluded, it wasn’t energy that had moved through the system – it was information.

“But,” an audience member demurred, “energy was involved in setting up the system so that it would work.”

Which Crutchfield cheerfully agreed with. What we’d seen, he argued, was an example of what he dubs intrinsic computing – a physical system that processes input (the initial push) based on past state (the actions that had put it in its current configuration) and transduces it to an output and a final state. Again, much like a big state-machine. (Fair warning: this sketch of the idea is written by a computer science Ph.D. dropout with not much background in physics or biology, based on a one-hour lecture, so I make no guarantees for its accuracy; it’s the impression of the idea that I took away. Time permitting, I would like to dig into some of the actual publications and get a better idea of the math, but I haven’t done that yet.)

Obviously humans make such systems for our own purposes, like writing natural history blogs and playing Skyrim; but if you look at biology and even fundamental physics through this lens, intrinsic computing appears everywhere, from single cells down to turbulent flows – phenomena that don’t have brains or nervous systems. Half-facetiously Crutchfield tossed out the question of what Nature does all this for – “a big optimization problem, to maximize the glory of God?”

Which let him loop back to another major, historical, point – faced with a phenomenon that does apparently complex computation, such as the physics of solar systems or life on Earth, there’s a human tendency to abstract it to a mind with a personality – a “demon”. As these phenomena become understood, the demons are “exorcized” – mystery, as he put it, becomes mechanism.

I’ve given shorter shrift to another major thread of the talk, which is the idea that humans call the behaviour of a system “interesting” when it lies in between the utterly predictable and the totally chaotic – that it has both predictability and variation. And in fact that this isn’t just a human aesthetic, but a characteristic of successful life; and given that, yielded an answer to another half-facetious question:

“Why isn’t everything disorganized? In fact, what are we all doing here tonight?”

Not questions with obvious answers, but being there and not some place else turned out to be a pretty good choice. Thanks of course to James Crutchfield for an engaging talk, and to the C4 for putting it on.

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