The Jesus Christ cricket: it jumps from the water

December 4, 2012 • 6:46 am

Some mesoAmerican lizards of the genus Basiliscus are known as “Jesus Christ lizards” because they can run across the water for considerable distances, using flaps on their toes to create air pockets that help them gain traction.  I actually saw this behavior in Costa Rica. Here’s a video of one:

But now there’s a Jesus Christ cricket, too (the monicker is mine). It’s a pygmy mole cricket, Xya capensis, found at the southern tip of Africa. The cricket lives in burrows near the water, and sometimes mistakenly jumps into the water. But it can get out! A new paper in Current Biology by Malcolm Burrows and Gregory Patrick Sutton (free pdf at link) tells us how:

We show that flightless pygmy mole crickets use a new strategy to jump rapidly from water. Their powerful hind legs are moved so quickly that they penetrate the surface and as they move through the water, unique arrays of spring-loaded paddles and spurs fan out to increase surface area. This enables these insects to propel a large volume of water downwards in a laminar flow, so that they are launched upwards into the air.

Here’s one of them, showing the hind leg which contains the paddles and spurs. Note how small it is: about 6 mm long, or about a quarter of an inch:

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An SEM photograph of the tip of the hind leg showing the three “medial” and four “lateral” paddles, and two pairs of spurs. The bar is 500 microns long, or about 1/50th of an inch.

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When these guys find themselves in the water, they hold their hindlegs above the surface and then plunge them into the water, extending the paddles and spurs which, according to the authors, increases the surface area of the leg 2.4 times and propels the cricket upwards. Then, just before the leg leaves the water, the extensions are folded up, presumably to avoid surface tension. Their bodies also emerge nearly perpendicular to the surface (84±8 degrees), which minimizes drag.  Here’s the sequence (photographed from several jumps); note that the paddles are extended in the first four photos but then retracted:

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How far can they jump on water? The authors say they can reach 10 cm high (about 4 inches) and 3 cm forward (a bit more than an inch, but 5.4 body lengths).

The paddles and spurs are unique to this family of insects (Trydactylidae):

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For those of you who want hard data, here’s a plot of the velocity of the animal and the angles of spurs and paddles with time as the cricket jumps from the water. Note that the spurs and paddles are retracted about four milliseconds (0.004 seconds) before the cricket emerges from the water.

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The photo below, taken under both white and UV light, shows the articulation of the paddles: where they attach to the leg. The blue fluouresence shows the presence of the elastic protein resilin, which, the authors say, “suggests that the folding of the paddles and spurs, and hence reduction of drag, is effected by springs.”

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Finally, a video of the leap, courtesy of reader Michael:

Here’s one of the paper’s authors, Michael Burrows, talking about how he learned about these crickets and a bit about the new research:

Besides the Jesus Christ lizard, some frogs are also capable of jumping from the water, though I don’t know which ones. But the cricket has an entirely different strategy. As the authors note at the end of their paper:

This locomotory strategy differs from those of other animals that jump from or move on water. Pygmy mole crickets generate a laminar flow of the water beneath their hind tibiae and large forces from extension of their moveable paddles and spurs. The generation of thrust is possible because of the viscosity of water relative to body size; the paddles and spurs act in a similar way to the smaller hairs on the moving mouth parts of copepods . By contrast, frogs and basilisk lizards generate a turbulent flow beneath their wide and flat feet (Reynolds numbers 5000–15000) and to run on water, a basilisk lizard must maintain a pocket of air above its feet. Pygmy mole crickets and copepods therefore exploit the viscosity of water, basilisk lizards its mass, and pond skater insects, and fisher spiders its surface tension. Jumping from water by pygmy mole crickets results in a lesser performance than when jumping from land, but the price paid for overcoming the drag from the water should be repaid in higher survival rates.

The last sentence, of course, shows the adaptationist program here: the crickets can’t jump all that well from the water, but Burrows and Sutton presume that the leg adaptations nevertheless conferred a higher survival rate compared to crickets lacking them.  That seems a reasonable assumption, though, given the specificity of the paddles and spurs and a reverse-engineering analysis of how they’re used.

Knowing nothing about “fisher spiders,” I looked them up, and found that these animals, in the genus Dolomedes, can run across water to catch aquatic insects and small fish, which they detect by ripples in the water. I couldn’t find a good video of one hunting, but here is one walking on water. It’s a miracle!

One of our readers Al Denelsback, has a nice post about fishing spiders on the website Walkabout; have a look. And a reader has posted two other videos of them in the comments.

h/t: Florian, Michael

____________

Burrows, M. and G. P. Sutton. 2012.  Pygmy mole crickets jump from water. Current Biology Volume 22, Issue 23, R990-R991,doi:10.1016/j.cub.2012.10.045

Dreadful science journalism: Time Magazine’s nomination of the Higgs boson for “Person of the Year” is five sentences long, each one wrong

December 4, 2012 • 5:00 am

Well, Time Magazine has tried to do science an honor by nominating a particle, the Higgs boson, for “Person of the Year” (there are other candidates and the winner will be announced in April). As Michael Moyer writes on the Scientific American “Observations” website, every sentence in the nomination has at least one error.

Here’s Time‘s nomination; I’ll let you spot the errors. After you try, go see Moyer’s piece for the post mortem. I’ve put one sentence in bold, which will be taken apart below:

Take a moment to thank this little particle for all the work it does, because without it, you’d be just inchoate energy without so much as a bit of mass. hat’s more, the same would be true for the entire universe. It was in the 1960s that Scottish physicist Peter Higgs first posited the existence of a particle that causes energy to make the jump to matter. But it was not until last summer that a team of researchers at Europe’s Large Hadron Collider — Rolf Heuer, Joseph Incandela and Fabiola Gianotti — at last sealed the deal and in so doing finally fully confirmed Einstein’s general theory of relativity. The Higgs — as particles do — immediately decayed to more-fundamental particles, but the scientists would surely be happy to collect any honors or awards in its stead.

Well, I’ll let you see one error: here’s Moyer’s dissection of the penultimate sentence in bold.

Error: Where to begin? Let’s start with Einstein. I honestly have no idea why the author would make any connection between the Higgs and general relativity. None! Because there is none. Einstein did teach us that energy and mass are two sides of the same coin (and that insight is a consequence of his special, not general, theory of relativity), but this teaching works at cross purposes to the author’s repeated assertions that the Higgs somehow transforms energy into matter.

Not to mention that no scientific theory could ever be “finally fully” confirmed. What would it mean for a scientific theory to be “finally fully” confirmed? Is he suggesting that no evidence could ever arise that could challenge it? Purely mathematical theorems can be proven. Scientific theories can only be disproven.

And then there’s the attribution problem. The author cites “a team” of three researchers that discovered the Higgs. He’s only off by three or four orders of magnitude. Two experiments at the LHC—ATLAS and CMS—independently confirmed the discovery this summer. Each of these experiments is made of about 3,000 working physicists. At the time of the announcement, Incandela and Gianotti were leading each of the experiments, but leaders change all the time (Incandela has led CMS for less than a year, for example), and the Higgs discovery has been a multi-decade long project.

Picture 1

Addendum: cat contest

December 4, 2012 • 3:51 am

As I mentioned a few days ago, if you can make your own LOLcat (from your own cat) with a piece of paper and a good photo, you might win an autographed book. Deadline for submitting photos is Jan. 1.

You need not make your cat into a bucktoothed cat. Be creative.  The bucktoothed cat I showed was only an example, and there are other ways to be creative (see below). However, you must show part of your cat’s face. And no costumes! (This is getting more complicated than I envisioned.)

Now get busy!

Only an example!
Only an example!

catbag2

catbag

First use of OMG—in 1917!

December 3, 2012 • 5:03 pm

According to Time magazine, the first recorded use of “OMG” as an abbreviation for “Oh, my God!” wasn’t this decade. It wasn’t even in this century. It was in 1917, in a letter from Lord John Arbuthnot Fisher (the famous “Jacky” Fisher who headed the British Navy during WWI and resigned after Gallipoli).

This makes Lord Fisher an official teenager.

Here’s the letter:

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Fisher and Churchill:Fisher%26Churchill

Why can’t they ever spell?

December 3, 2012 • 11:47 am

From wannabe poster “Jane,” who, needless to say, will not be commenting here again. She’s referring to my remark about Ricky Gervais not taking the free-will issue seriously enough:

anyboby notice how jerry gets upset when free will is mentioned and that ricky and richard dont buy into this lack of responsibility. Jerry has to deny praise and blame because he did nothing in his life and let his parents down. Watch him sqirm when free will is mentioned and he goes on the defence of his postion straight away. ” I cant be blamed, its not my fault mom and dad!”. Be an adult Jerry like Ricky said!!! Lol your pathetic

I suspect “Jane” is a 14-year-old boy with sexual issues who hangs out in front of a computer in his parents’ basement.  And speaking of “Jane’s” parents, they’d be prouder of him/her if he/she would learn to write and spell!

Birds of paradise: photos and a great video

December 3, 2012 • 11:35 am

The Guardian‘s environment section features eight beautiful pictures of the birds of paradise, a group comprising 40 species in the family Paradisaeidae.  They’re mostly limited to New Guinea, but a few occur in Australia or on other islands. The Guardian site explains the photos:

On a mission to become the first to document all 39 species of birds of paradise, the photographer Tim Laman and ornithologist Ed Scholes have spent nearly a decade sleeping in tents and dangling from the rainforest canopy. Their work will be featured on Secret Birds of Paradise on 6 December at 8pm on Nat Geo Wild

Here are four of the photos. The last, Wilson’s bird of paradise, is the most bizarre!

Victoria's Riflebird bird of paradise. Photograph: Tim Laman/National Geographic
Victoria’s Riflebird bird of paradise. Photograph: Tim Laman/National Geographic
Adult male King of Saxony bird of paradise. Photograph: Tim Laman/National Geographic
Adult male King of Saxony bird of paradise. Photograph: Tim Laman/National Geographic
Red bird of paradise. Photograph: Tim Laman/National Geographic
Red bird of paradise. Photograph: Tim Laman/National Geographic
Wilson's bird of paradise. Photograph: Tim Laman/National Geographic
Wilson’s bird of paradise. Photograph: Tim Laman/National Geographic

And, to top it off, here’s a fantastic video showing some of the species featured in the National Geographic documentary (filmed with assistance of the Cornell University Laboratory of Ornithology). It aired November 22, but I wasn’t aware of it. You really need to watch this to see what bizarre features and behaviors can result from sexual selection.

Of course, in none of these cases do we know the precise form that sexual selection took. That is, was it set off by a pre-existing female preference that differed among already-formed species?   Was it due to the “runaway process,” the “good genes model,” or perhaps “antagonistic sexual selection”? Do we know whether exual selection caused the species to form in the first place from a common ancestor (other reproductive barriers might have been completed before the sexual differences evolved).

Understanding how such morphologies and behaviors arose is one of the hardest questions in evolutionary biology, for we’re trying to reconstruct evolutionary forces that operated in the distant past. And there are many different theories of how sexual selection gets started, and few ways to distinguish among them in a given case.

h/t: Matthew Cobb

“If you’re bored, you’re doing something wrong”: Dawkins and Gervais discuss religion and science

December 3, 2012 • 5:55 am

Here’s a 15-minute conversation between Richard Dawkins and Ricky Gervais—apparently in a church! The caption on the YouTube video isn’t really accurate:

A surprisingly respectful yet critical look at religion and science. This is full interview. Snippets of this were used in Richard Dawkins recent documentary for more4.

It’s not all that “respectful”! Gervais evokes feelings of wonder, and claims that religion becomes harmful only when the faithful start making policy from their beliefs, but that’s about as respectful as it gets.

I like the “childlike” wonder that pervades the discussion, especially when Richard explains the neuronal impulses that are really behind their conversation.  The issue of free will comes up, and Gervais professes uncertainty about whether we have it, but says that because he feels like a free agent, in the end it doesn’t matter. But it does, for whether our wills are “free” has profound implications for societal policies of punishment and reward.

At 10:20, Gervais explains why agnostics annoy him more than do the faithful.  I don’t quite agree if you define “agnosticism” as “profession of no knowledge about God.” Scientifically, that’s the right attitude, and yes, one can (contra Gervais) be agnostic about fairies.  All that means is that we have no evidence for fairies, and of course scientists never professes absolute certainty.  As Dan Barker says, “agnosticism” is about lack of evidence and “atheism” is about lack of belief.  You can, I think, be both an agnostic and an atheist, and some agnostics are nevertheless theists.

h/t: Michael

Rupert Sheldrake peddles his woo to Americans

December 3, 2012 • 5:26 am

Where else but at PuffHo, the bailiwick of Chopra and Jenny McCarthy? You do remember Rupert Sheldrake, right? He’s a woo-meister, like Chopra, but even worse since he pretends to be a good scientist. Indeed, he was trained as one, though he seems to have gone off the rails.

Author of The Science Delusion (endorsed by both Mary Midgley and Mark Vernon!), Sheldrake thinks that the facts that dogs and pigeons can find their way home is evidence for God. Other evidence for God includes his “demonstration” (not substantiated by other workers) that people know when other people are looking at their backs. His Big Theory is that organisms have “morphic resonance,” a kind of inherited species memory (think Jung) that helps shape their bodies and behaviors. When others have tried to repeat his experiments demonstrating “morphic resonance,” they’ve also failed. He’s a pseudoscientist with scientific credentials.

Sheldrake also sees genes as being of minor importance in shaping bodies and behaviors, and, above all, decries naturalism and materialism as the proper way to do science. He prefers nebulous forms of woo, and that’s what The Science Delusion is about. It’s now been issued in the U.S. under the irritating title of Science Set Free: 10 Paths to New Discovery.

For some reason the Brits love Sheldrake (not all of them!), and he’s far more popular in the U.K. than the U.S., proving that Brit(on)s are not immune to woo.

To remedy this situation, and flog his book to Americans, Sheldrake has written a mooshy piece at PuffHo, “Why bad science is like bad religion.” (At least it’s in PuffHo‘s “Religion”  section instead of the “Science” section.)  I haven’t read his book, and won’t, for I need to read more substantive stuff—like theology. But  I’ll reprise Sheldrake’s antimaterialistic contentions in the PuffHo piece. It all comes down to the contention that while a lot of religion is “bad” (Sheldrake cites fundamentalism), a lot of science is even worse.

What does Sheldrake mean by “bad science”?  He means materialistic science:

Science at its best is an open-minded method of inquiry, not a belief system. But the “scientific worldview,” based on the materialist philosophy, is enormously prestigious because science has been so successful. . .

Science has been successful because it has been open to new discoveries. By contrast, committed materialists have made science into a kind of religion. They believe that there is no reality but material or physical reality. Consciousness is a by-product of the physical activity of the brain. Matter is unconscious. Nature is mechanical. Evolution is purposeless. God exists only as an idea in human minds, and hence in human heads.

There’s that perennial equation of science with religion. (Don’t these people know that when they make this comparison to debase science, they’re implicitly debasing religion as well?)  But we don’t, of course, have faith that there is no reality but material reality: that attitude is simply a good working assumption, and, as Laplace affirmed, we haven’t seen the need to assume otherwise.  And if there were evidence for “nonmaterial” phenomena, like ESP or telekinesis, I’d be glad to consider it.  In contrast, the Pope won’t consider embracing Islam.

According to Sheldrake, who really wants to believe in woo, science is actually being impeded by its commitment to naturalism:

As I show in my new book, “Science Set Free,” unexpected problems are disrupting the sciences from within. Many scientists prefer to think that these problems will eventually be solved by more research along established lines, but some, including myself, think that they are symptoms of a deeper malaise. Science is being held back by centuries-old assumptions that have hardened into dogmas.

How have we hobbled ourselves by being naturalists? What are the problems that only woo can solve? Here’s his list:

  • We don’t understand organismal development, which, according to Dr. Sheldrake has made no progress.  Anybody who has followed the field will simply guffaw at words like these:

“Despite the confident claim in the late 20th century that genes and molecular biology would soon explain the nature of life, the problems of biological development remain unsolved. No one knows how plants and animals develop from fertilized eggs. Many details have been discovered, hundreds of genomes have been sequenced, but there is still no proof that life and minds can be explained by physics and chemistry alone.”

That’s either sheer ignorance or, more probably, a lie.  We’re beginning to understand development in a big way, and it’s materialism (and genetics!) that have helped. Hox genes, anyone? Of course we’re a long way from understanding how one goes from a DNA recipe to an organism, but it’s early days yet. Sheldrake prefers not to ponder the exciting path ahead, and fob our ignorance off on God (he’s an Anglican).

  • We don’t understand the brain or consciousness.

“Despite the brilliant technical achievements of neuroscience, like brain scanning, there is still no proof that consciousness is merely brain activity. Leading journals such as Behavioural and Brain Sciences and the Journal of Consciousness Studies publish many articles that reveal deep problems with the materialist doctrine. The philosopher David Chalmers has called the very existence of subjective experience the “hard problem.” It is hard because it defies explanation in terms of mechanisms. Even if we understand how eyes and brains respond to red light, the experience of redness is not accounted for.”

This is again a woo-of-the-gaps stance. It will take us decades and decades to understand the brain, for that’s one of the hardest problems of biology (if not the hardest), but the materialist program has already made substantial progress. As for consciousness not being a product of brain activity, that’s hogwash. You can alter consciousness with material drugs. You can remove it by removing brain activity, like killing someone (and there’s no evidence of consciousness with brain death!).  You can temporarily remove consciousness with anesthetics, and restore it by removing them.  Disease or brain lesions alter consciousness, often in predictable ways.  Yes, we don’t yet know the mechanism of consciousness, or how we perceive “qualia” like redness, but should we throw up our hands and cry “God did it!,” or should we get to work?

  • We don’t understand cosmology.

“In physics, too, the problems are multiplying. Since the beginning of the 21st century, it has become apparent that known kinds of matter and energy make up only about 4 percent of the universe. The rest consists of “dark matter” and “dark energy.” The nature of 96 percent of physical reality is literally obscure.

Contemporary theoretical physics is dominated by superstring and M theories, with 10 and 11 dimensions respectively, which remain untestable. The multiverse theory, which asserts that there are trillions of universes besides our own, is popular among cosmologists in the absence of any experimental evidence. These are interesting speculations, but they are not hard science. They are a shaky foundation for the materialist claim that everything can be explained in terms of physics.”

Yep, physics is full of exciting puzzles, and the answers will no doubt be counterintuitive and a cause of great wonder. But think of all the progress that physics has made using the materialist paradigm! Just to name a recent one, physicists predicted the existence of the Higgs boson and then found evidence for it.  The Standard Model of particle physics is a pretty good paradigm.  We now know that the universe is about 14 billion years ago and originated in a huge expansion event.

Yes, dark matter and dark energy remain puzzles, but is that a reason to accept God?

In the end, of course, Sheldrake is simply relying on god-of-the-gaps arguments.  Because we don’t understand everything at present—and if we did we wouldn’t need science!—there must be a Big Anglican Father in the Sky who does things like create consciousness and dark matter. What a crock!  The history of science has been filling in the gaps, one after the other, that used to constitute evidence for God.  And that caulking has all been done by materialism.  Doesn’t that suggest that materialism will fill the gaps that remain? We haven’t understood a whit more about the universe by relying on deities and spiritualism.

And, OMG, he ends with such a trite admonition:

Good science, like good religion, is a journey of discovery, a quest. It builds on traditions from the past. But it is most effective when it recognizes how much we do not know, when it is not arrogant but humble.

As if we don’t recognize what we don’t know!  Every working scientist implicitly admits that, for science is based on ignorance. It is not the scientists who are arrogant, but the faithful, who assert things about the existence and nature of God for which there’s not the slightest evidence. When you see an accommodationist calling for scientists to be “humble,” you know that they have no other cards to play.

Yes, dogs can find their way home, and so can pigeons.  And, at least for pigeons, we’re starting to understand how they do it. But I wish Sheldrake would find his way home, to a church instead of science. I despise his ill-conceived incursions into science, for they have no evidential basis and only serve to succor who believe that there is Something Out There besides material stuff.  He’s worse than a creationist, because he’s a faith-head in scientist’s clothing, but, unlike Francis Collins, keeps that to himself.

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The Argument from Lost Dogs