Why Evolution is True is a blog written by Jerry Coyne, centered on evolution and biology but also dealing with diverse topics like politics, culture, and cats.
Nothing fancy this week: I am still enervated from my illness and the onslaught of (Dr.)3 Pigliucci. Instead, I offer a few videos I’ve been saving up.
You might be familiar with the famous Simon’s Cat animation “Cat Man Do,” in which a wily felid awakes his owner. Well, here’s the real Simon’s cat. It’s 6 hours and 19 minutes of fun compressed into a single minute. That cat wants his noms!
while the other is satisfied with a moist, raw spud:
In May, four Amur tigers were born at the Denver Zoo. Here’s one getting his checkup (20 seconds in): look how stoically he takes a thermometer up the butt. My fondest wish is to pet a baby tiger before I die. The Brookfield Zoo actually had some, but when I made a grovelling request, I was denied with talk about insurance and the like. It was intimated, however, that if I were willing to donate big bucks to the Zoo. . . . Any readers out there with access to baby tigers?
The title is taken from from a wonderfully derisive analysis of Thorstein Veblen’s pompous pishposhby H. L. Mencken. (I had to read The Theory of the Leisure Class as a teenager, and still haven’t gotten the bad taste out of my mouth.) Mencken’s line is still one of the funniest bits of a book review I’ve ever seen, and applies as well to another professor, one Dr. Massimo Pigliucci. Once again Pigliucci has taken up the cudgels against me on his website Rationally Speaking, and I swear that I can’t find anything new in his complaints. In fact, after poring over his boobish persiflage several times, I conclude that his real issues are these:
1. He doesn’t like me
2. He thinks I don’t know anything about philosophy and therefore I—and most other scientists—should shut up about it.
Pigliucci’s beef is a quotation of mine (which, by the way, I stand by completely): “Anybody doing any kind of science should abandon his or her faith if they wish to become a philosophically consistent scientist.” He characterizes this as “philosophically very naive and pretentious,” asserting that I have no fricking idea what “philosophically consistent” means. He then makes a lot of other assertions, all of which boil down to saying that scientists should keep their noses out of philosophy because it’s simply too hard for us.
I have just arisen from the sickbed. I am lightheaded, spots dance before my eyes, and I’d rather do anything than answer the sweating professor. But duty calls. I’ll address Pigliucci’s claims, but may in this instance be unduly petulant.
“Conceptions of gods. . . are simply not falsifiable.” Sweet Jebus, I have dealt with this before, and Pigliucci knows it. Once again: yes, one cannot falsify the idea that there is a transcendent being. But one can falsify the idea that there is a transcendent being who, it is claimed, does specific things. If you think that God answers prayers, heals the sick, created life de novo, and so on, then aspects of your God—which, after all, are parts of your conception of a God—are testable and falsifiable. I freely admit that a watery deism, embracing a God who doesn’t do anything tangible, is not a hypothesis that can be falsified by science. I really don’t know why Pigliucci, who so loudly proclaims his philosophical sophistication, can’t grasp this simple distinction.
It seems to elude others, too. A while back I argued this point with Eugenie Scott, who told me that “Science can’t test the supernatural.” I told her that it could test claims about the supernatural: if native Americans believed that dancing to propitiate the gods brings rain, then you could in principle test this. Just set up an experiment in which believers either dance or refrain from dancing at particular times of drought, and correlate that with the arrival of rain. For some reason Scott didn’t see this as a test of the supernatural. I will say it once again: you cannot test the mere existence of gods, but you can test claims that your gods do something, that is, interact with the world.
I’d be delighted to hear why this simple point escapes so many.
“It unnecessarily flatters and elevates religious belief to treat it as a science.”On this point atheists like Pigliucci agree with “sophisticated” theologians. But who ever said that Christianity or Mormonism or Islam were sciences? They’re not—they’re religions. But they make empirical claims that are testable (see above), and so can enter the bailiwick of science.
“Indeed, even science itself is far from being an activity rooted in reason alone.” This took me aback. What Pigliucci means here is that new theories don’t always arise from rational contemplation: they may have sources in intuition, the unconscious or even—as in the case of Kekulé’s discovery of the benzene ring—in a daydream. So what? Ideas can come from anywhere, but only a subset of ideas are scientific ones, and only a subset of those pass empirical muster and become accepted science. I have no idea why Pigliucci brings up this point except, as he says because it “would make Coyne and colleagues even more unhappy, because it goes in the direction of further reducing the relevance of reason to the scientific enterprise.” This seems to be part of Pigliucci’s campaign to inflate philosophy at the expense of science.
It is naive and pretentious to claim that a religious scientist is not “philosophically consistent.” I’m still not clear why Pigliucci finds this claim naive. What I mean by “philosophical consistency” is that one’s philosophies are consistent. In the case of a scientist, one’s scientific philosophy is that you don’t accept the existence of things for which there is no evidence. In the case of a religious person, your philosophy requires you to believe in things for which there is either no evidence or counterevidence. It’s just that simple.
Further inconsistency comes from the fact that science and faith find out things in different ways: scientific knowledge is attained through observation, experimentation, and agreement among practitioners. “Religious knowledge” (and I put it in quotes because it’s an oxymoron) comes from dogma, authority, and personal revelation. This leads to the final inconsistency: the stuff that religion “finds out” contradicts what science finds out. As Russell Blackford has pointed out, in principle there’s no reason why God (or religious faith) couldn’t have led us to the truth about the universe. The Bible, after all, could have been full of stuff that was true, even telling us about evolution or the age of the universe. But it doesn’t. Large swathes of the American public still think that the Earth is a few thousand years old and that life did not evolve. More sophisticated swathes think that, well, maybe life evolved but humans were designed, complete with a soul. The inefficacy of faith in understanding the world is, of course, the reason why all those faiths come up with mutually contradictory “truths.”
I’m not saying anything new here, and God knows I’m tired of saying it again and again. Perhaps the sweating professor will let me rest at last and start in on his co-blogger Julia Galef, who also sees the philosophical contradiction involved in being a religious scientist.
Oh, and as for “pretentious”, I’d respectfully ask Pigliucci to look in the mirror, since his whole post is marinated in arrogance and contempt for those who, without the proper Ph.D. in hand, dare say anything that he construes as “philosophy”:
But when it comes to writing for the general public, I suggest that scientists stick to what they know best, unless they are willing to engage the literature of the field(s) that they wish to comment upon. When Coyne makes statements of the type “anybody doing any kind of science should abandon his or her faith if they wish to become a philosophically consistent scientist”, he literally does not know what he is talking about because he does not have a grasp of what it means to be “philosophically consistent” in this context. He has of course no obligation to study philosophy, but then he should refrain from writing about it as a matter of intellectual honesty toward his readers.
Here’s Christopher Hitchens’s nine-minute interview with Anderson Cooper last night.
Cooper brings up the question that everybody wants Hitchens to answer, and I must say that it never crossed my mind. If you think he’d abandon his principles for God on his deathbed, then you either don’ t know him or think he’s been lying all along.
Cooper: In a moment of doubt, isn’t there? . . I just find it fascinating that even when you’re alone and no one else is watching, there might be a moment when you want to hedge your bets.
Hitchens: If that comes it will be when I’m very ill, when I’m half demented either by drugs or by pain and I won’t have control over what I say. I mention this in case you ever hear a rumor later on—because these things happen, and the faithful love to spread these rumors, “On his deathbed. . .” Well I can’t say that the entity that by then wouldn’t be me wouldn’t do such a pathetic thing, but I can tell you that “Not while I’m lucid, no.” I can be quite sure of that.
Cooper: So if there’s some story that on your deathbed.. .
USA Today has finally put up my ten-minute video debate with Karl Giberson, vice-President of the BioLogos Foundation. The topic: Are science and faith compatible?
I haven’t watched this version due to viral malefaction, but I remember that the audio and video were a bit rough. But hey, how often does a poor atheist boy get to say this kind of stuff in a place like USA Today?
Two things come together from earlier this year. First, there was a lot of argument here, in the Times Literary Supplement and elsewhere over Stephen C. Meyer’s Signature in the Cell. One of the many issues in questionwas the ancient “RNA world”, which Meyer has argued is implausible. Then, in May, there was Craig Venter’s amazing creation of an artificial organism (but not an artificial cell), which Jerry rightly said was indeed “playing God”.
Now there’s an excellent 30-minute BBC Radio 4 programme “Acts of Creation” which puts the two stories together, and looks at attempts round the world to push the field of “artificial biology” even further. The “RNA world” refers to the suggestion that before life used DNA as the universal genetic code, its simpler, more fragile sister, RNA, was the molecule of life – around 4 billion years ago.
One of the problems with this idea is that precisely because RNA is so fragile, it is very difficult to imagine molecules of it sloshing around in Darwin’s “warm little pond” without simply degrading. Venter’s competitors – including my Manchester colleague John Sutherland – are trying to see under what conditions life might have originated. And one of the answers – or rather, one of the leading hypotheses – is remarkably cool. Literally.
You should be able to listen to the programme from anywhere in the world by going here. If it won’t play outside the UK, my sincere apologies, but you can still follow the links to the various labs that are working on this fascinating area.
[Jerry’s poorly at the moment, so he’s invited his guest bloggers to pitch in. Get well soon, Coyne!]
Photograph: H Bahena/Texas A&M Press
This fantastic picture is of a Hyperiid amphipod – a small (1.5 cm) shrimpy thing, but most definitely not a shrimp. It is one a set of photos that has been going the rounds in the media, following a recent series of publications by the Census of Marine Life – an international network of marine scientists. This set of 16 beasties appeared in The Guardian.
The CoML folk estimate there are around marine 230,000 species (seems pretty low to me), and describe their findings in a series of articles in the PLoS ONE open access journal. These include one with the great title “Deep-sea biodiversity in the Mediterranean Sea: The known, the unknown, and the unknowable”. All highly recommended.
But back to the amphipod. But what caught my attention was the caption given to it by The Guardian: “Pelagic amphipod, Phronima sedentaria. It travels in a ‘house’ that is a cylindrical-shaped organism whose body has an opening on both ends. Gulf of Mexico.”
A quick Google reveals that according to photographer Solvin Zanki, Phronima inspired weirdo artist H.R. Giger in his design of the Alien in Ridley Scott’s film of the same name.
Apart from hoping that P. sedentaria and its pals live way away from the Deepwater Horizon spill, I was intrigued by the “house”: what kind of organism is it, and why on earth would it accept having a shrimp-that-isn’t-a-shrimp living inside it?
The answer to the first question is remarkable. The “house” is a thing called a salp, and its an animal. Looking at it, you might think it was something like a jellyfish, but not at all. It has a well-organised nervous system and is in fact a chordate, just like you and me and my cats. More specifically, it’s a tunicate, like a sea squirt.
The anatomy of a salp
This diagram from the Tasmanian Aquaculture and Fisheries Institute, shows the salp’s structure – it has a series of circular muscles going round the body, a mouth, an anus, and a through gut. It moves – and eats – by ingesting water and squirting it out through its rear end. As well as being a neat trick requiring neuronal coordination, these fecal pellets form an important part of the marine ecoystem. As K. Iseki wrote in 1981:
“Free-floating sediment traps were suspended at 200 and 900 m in the northern North Pacific Ocean during 20-21 May, 1974. A considerable amount of large, dark-green particles, larger than 1 mm in diameter, was collected at both depths. These large particles corresponded morphologically with fecal pellets of salps. Vertical carbon flux was estimated to be 10.5 and 6.7 mg C m-2 d-1 at 200 and 900 m, respectively. This suggests that vertical transport of salp fecal pellets could play an important role in meeting the energy requirements of bathypelagic organisms in the open ocean.”
Salp are a particularly important of the zooplankton, and together with the more widely-known krill, they consume vast quantities of phytoplankton. Due to increases in salp numbers in the Southern Ocean, apparently due to global warming, the krill may be being replaced by salp within the Antarctic marine ecoystem. This in turn might have unknown consequences on larger, more photogenic marine animals.
The excellent jellieszone.com has this summary of the complicated salp life-cycle (wake up at the back, there will be a quiz later on):
“Salps can form massive aggregations of millions of individuals that may play a significant role in marine ecosystems. They exhibit among the fastest growth rates of any multicellular organism. (…) Salps exhibit a complex life cycle with alternating aggregate and solitary generations. Aggregates (the sexual gonozooids) develop asexually from an elongating stolon that buds from an area just behind the endostyle of the solitary individuals (the oozooid). Individuals within aggregates are hermaphrodites, typically starting as females that are fertilized by older male individuals from another chain. The resulting embryos (oozooids) then develop into the solitary asexual phase. There is no larval stage and even before release the young oozooid often has a developing stolon. In many species only a single embryo develops within each individual of the aggregate. This method of asexual reproduction enables salps to quickly exploit periods of abundant food with rapid increases in population density.”
The article concludes where we began:
“Hyperiid amphipods and several species of fish also use salps as traveling homes.”
Now from the amphipod’s point of view the relationship with the salp seems quite understandable – it could serve as some kind of protection against predators, or maybe save them energy.
But what does the salp get from transporting P. sedentaria up and down the water column? The answer appears to be: nothing. As the webpage of Sönke Johnsen’s lab at Duke University puts it, the “house” is nothing more than “a hollowed-out salp test” (the test is the salp’s “shell”). This suggests to me that the salp has died or discarded the test, and the amphipod simply takes up residence, like a hermit crab.
Things are in fact more complicated, more fascinating and more gruesome.
In 1978 Philippe Laval from Villefranche in France, measured 70 “houses” fished up from the sea off Nice and subjected his findings to some complicated statistical analysis. He found that the houses broke down into five groups and belonged to either salps or pyrosomes (another form of tunicate that can bioluminesce).
Amazingly, it seems that the “house” is actually sculpted by the amphipod:
“It was shown that all the tissues were carefully removed by the amphipod (in salps as in pyrosomes), leaving only the tunic. (…) The inner surface is generally scraped off, perhaps to eliminate decomposing secondary ascidiozooids remaining in the test after zooid extraction. The inner surface is extremely smooth, as though finished with a fine cutting tool on a lathe. This could explain, besides the high variability, why principal component analysis did not disclose distinct groups of barrels. The inside is always made hollower in the middle, so that the wall is thicker at both ends. Less rigidity in the middle could produce the swelling leading to the barrel-like shape, but there could be also a mechanical distention by the rotating amphipod before tunic consolidation.”
On reading this, I assumed the tunicate had been eaten before all this sculpting and scraping went on. Not at all. Laval concludes, with words that suggest the relationship with the Alien is not merely morphological:
“Finally, the relationship between Phronima and its barrel deserves some consideration. It is not in essence predaceous, because salps or pyrosomes are not primrily used as food (although they may be, besides making a barrel); moreover, the amphipod remains with – within – its partner. It is rather a borderline case of parasitism, soon fatal to the host, which is killed to obtain advantages from its tunic. Some hermit crabs are known which similarly kill and eat molluscs before occupying the shells (Rutherford, 1977). Most of the hyperiid amphipods (if not all, as postulated by Harbison et al., 1977) are parasitic on pelagic animals. Phronimids, which deposit their larvae in the barrel, as do many hyperiids on their hosts (Laval, 1965), are not exceptions to the rule. By killing their host and removing its soft parts to prevent decay, they only go a step further and thus approach the margins of predation.”
To complete the story, in 2005 Euichi Hirose and co-workers studied seven “houses” and suggested they were indeed still alive – cells were still alive and there were no bacteria in the barrels, suggesting there was some kind of antibiotic system in there. And Renée Bishop & Stephen Geiger looked at the energetics of being a Phronima compared to other crustaceans and concluded:
“Although less energy is needed to remain in the water column since the gelatinous zooplankton makes the Phronima more buoyant than just Phronima alone, metabolicrates of Phronima are not lower than those of other pelagic crustaceans, possibly due to the energy needed to propel the barrel. However, Phronima have lower protein concentrations, indicating less energy is allocated to muscle production. The ratio of LDH (L-lactate dehydrogenase) activity to CS (citrate synthase) activity was >1, indicating that burst swimming is important in Phronima‘s metabolism. The symbiotic relationship provides the Phronima with food and a substrate for the brooding of young, but does not give them an energetic advantage over other pelagic crustaceans.”
So they have a house and food, but they still have to swim!
That’s an awful lot of information to come from one intriguing photo…
. . . is the title of Christopher Hitchens’s new Vanity Fair piece about his illness. One thing is for sure: he hasn’t lost his brutal honesty, his sense of humor, or his ability to write.
In one way, I suppose, I have been “in denial” for some time, knowingly burning the candle at both ends and finding that it often gives a lovely light. But for precisely that reason, I can’t see myself smiting my brow with shock or hear myself whining about how it’s all so unfair: I have been taunting the Reaper into taking a free scythe in my direction and have now succumbed to something so predictable and banal that it bores even me. Rage would be beside the point for the same reason. Instead, I am badly oppressed by a gnawing sense of waste. I had real plans for my next decade and felt I’d worked hard enough to earn it. Will I really not live to see my children married? To watch the World Trade Center rise again? To read—if not indeed write—the obituaries of elderly villains like Henry Kissinger and Joseph Ratzinger? But I understand this sort of non-thinking for what it is: sentimentality and self-pity. Of course my book hit the best-seller list on the day that I received the grimmest of news bulletins, and for that matter the last flight I took as a healthy-feeling person (to a fine, big audience at the Chicago Book Fair) was the one that made me a million-miler on United Airlines, with a lifetime of free upgrades to look forward to. But irony is my business and I just can’t see any ironies here: would it be less poignant to get cancer on the day that my memoirs were remaindered as a box-office turkey, or that I was bounced from a coach-class flight and left on the tarmac? To the dumb question “Why me?” the cosmos barely bothers to return the reply: Why not?
That Dreher complains about a lack of civility one minute and then engages in snotty incivility the next is indicative of a common phenomenon among those who complain about the tone of blogs. The problem rarely seems to be incivility per se. Usually that is just a cover for the real complaint, which is seeing incivility directed towards people the writer does not think deserve it.
Absolutely true! I’ve lost track of those people who constantly call for civility while hurling invective at atheists and fundamentalists. Civility, it seems, is best practiced selectively.
And that’s precisely the problem with all the hand-wringing about tone, the worries about driving people away for excessive nastiness, and the fretting about what is and is not convincing to people. The same features that some people find offputting are precisely the ones that others find attractive. Discourse that drives some people away from your cause draws other people to it.
I don’t know which of those forces (the driving away or the drawing towards) is more powerful in this case. But I have noticed that P. Z. Myers currently gets more than a hundred thousand hits a day. Am I seriously to worry that his primary effect on the site is to drive readers away?
As we should all know by now, when you see an argument about tone, you see somebody who’s avoiding the substantive issues.
