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.
For you procrastinators, you still have 90 minutes (till 1 p.m. Chicago time) to enter the competition for a free copy of FvF, inscribed and illustrated (with a cat) to your specifications. Go here to submit your entry; I’ve disabled comments on this post so that entries will all be on thread.
The winner will be announced by Friday of next week.
JAC: We met Dorsa Amir a while back when she sent us photographs of the Barbary macaques she worked on in Morocco’s Atlas Mountains (she also sent a photo of her orange tomcat Emerson). She recently called my attention to Amy Cuddy’s popular TED video on “power posing”, as Cuddy’s conclusion about hormones and behavior is relevant to Dorsa’s thesis work. Not only that, but Cuddy’s talk, now up to 25,758,838 views, is the second most popular TED talk of all time. But, referring me to an analysis on another site, Dorsa told me that Cuddy’s conclusions were dubious—or at least non-repeatable. I asked her to write a post about it, which is below. I’ve also put in Cuddy’s talk, which I recommend you watch, so you can see her claims and how much the audience loved it.
First, Dorsa’s information:
I’m a PhD student in biological anthropology at Yale University. My research interests include the physiology and psychology of contemporary humans, with a focus on small-scale societies. I spend my summers in South America with the Shuar of eastern Ecuador, as part of the Shuar Health and Life History Project
Personal site: www.dorsaamir.com
*******
Pulling the Plug on Power Posing
by Dorsa Amir
If you’ve seen just one TED talk, I would bet it’s called “Your body language shapes who you are” by Amy Cuddy, now an Associate Professor at Harvard Business School. This is a pretty safe bet, for in the three years since its release, Cuddy’s talk has racked up more than 25 million views, making it one of the most popular TED talks of all time.
In the talk, Cuddy presents data from her 2010 article in Psych Science which makes the following claim: by simply changing your posture to a “high-power” pose (i.e., taking up more space and opening your limbs), you can instantly trick your body into thinking it’s more powerful. The authors tested this claim by having 42 participants give saliva samples, engage in either a high-power or a low-power pose for two minutes (depicted below), then give another saliva sample.
The saliva tubes were then sent off to a lab and analyzed for two specific hormones: testosterone and cortisol. Interestingly, the power posing appeared to have a significant effect on hormone levels: high-power poses were associated with a rise in testosterone and a drop in cortisol, and low-power poses with the opposite. So not only did the posing make you feel more powerful, it also made your body more powerful by fiddling with your hormone levels and making you literally embody that power.
DataColada vs. Power Posing:
So why are we talking about a video from three years ago? Well, in a blog post on Friday, the talented folks over at DataColada tackled the evidence supporting power posing. As it turns out, as shown in a recent paper in Psych Science, the power posing effect doesn’t seem to replicate. I suggest checking out the full blog post for details, but here are their main points:
As the bloggers claim, “if studies only get published when they show an effect, the fact that all the published evidence shows an effect is not diagnostic”. So what you can do, and what they did, is run a fancy statistical method called a p-curve analysis; a method that lets you rule out selective reporting as the only explanation for a set of significant findings.
Check out the two example graphs below, comparing a good to a bad p-curve. On the X-axis is the p-value reported in any one study, and on the Y-axis is the percentage of studies that have that p-value. This lets you compare p-values for the same experimental protocol across many studies and see what the curve looks like. You want a right-skewed curve because that indicates that proportionally more studies are reporting effects that are significant at lower values. So, if power posing is real and effective and robust, as assessed in 33 separate studies, you should see a right-skewed p-curve. You don’t want to see a flat curve, because that means that all the different p-values are equally likely to occur.
Here’s what the actual p-curve analysis looks like:
We see not the right-skewing that would convince us that this is a real effect, but rather a flattish curve that should make us question the finding.
The DataColada folks conclude, “At this point the evidence for the basic effect seems too fragile…to advocate for people to engage in power posing to better their lives.”
Hormones & Behavior:
I’d like to take a minute here to add my two cents. In our lab at Yale, my colleagues and I spend a lot of time thinking about hormones—our lab meetings are affectionately referred to as “Hormone Happy Hour”—and we spend a lot of these meetings discussing the relationship between hormones and behavior. As it turns out, hormones, like everything else in biology, are kind of complicated. While testosterone and cortisol have been implicated in basically every human behavior, let me share the basics. Testosterone plays a big role in male development by turning baby boys into pubescent boys, and in adulthood it makes muscles and semen happen. There’s no clear evidence that testosterone contributes to variation in aggression between individuals, but it’s likely to contribute to differences in aggression between the sexes [1], and there’s really good evidence that it helps you build big muscles[2,3]. Cortisol, contrary to popular belief, doesn’t cause stress, it’s just a response to stress: when your body senses that it’s in need, cortisol increases the amount of glucose in your bloodstream so your cells can have greater access to energy.
In general, hormones like testosterone and cortisol are dynamic. Both hormones have a diurnal rhythm, which means they change throughout the day. They’re also influenced by dozens of variables: the obvious ones like age, sex, and weight help determine clinical guidelines for what “normal” levels look like. One big problem here, though, is that if you look at men from different populations, such as hunter-gatherers, their absolute levels of both testosterone[4] and cortisol[5] are sometimes almost half of those found in American men.
Why is all this relevant to power posing? Well, there are three main points to be made: (1) hormones have complicated effects on behavior, (2) hormones often change throughout the day, and (3) the density and affinity of hormone receptors are potentially just as important as absolute hormone levels (excellent evidence here). How did Cuddy and colleagues control for these phenomena? In short: they didn’t. They took two saliva samples, prior to and following the manipulation, and attempted to control for diurnal rhythm by scheduling testing in the afternoon – a massive six hour window that stretched from 12:00pm-6:00pm. Due to the dynamic nature of cortisol, the standard cortisol assessment protocol generally involves something like two samples a day for 2-3 days. This means cross-sectional samples, like the one in the power posing study, must be analyzed with a grain of salt.
The best way to address the question of whether or not changes in hormone levels caused by the treatment are in turn causing a change in behavior is to run a mediation analysis. This is a method in which you try to test causality among three variables; in this case, you’d want to see that changes in hormones are mediating, meaning causally linking, high-power poses to more confidence. You don’t necessarily need to know all the details of this method (more info here), but the basic point is that the authors, for some reason, do not include this simple test in their paper. Without knowing what people’s hormonal profiles look like (by taking several samples across many days), it’s really hard to say whether or not you’re measuring a “trait” difference or a “state” difference.
A long-running debate in my field is the relationship between statistical significance and biological significance. Even if this treatment did cause significant changes in hormone levels (which the DataColada folks suggest we should doubt), we’re still left with open questions: does this treatment have any biological significance and if so, what are the proximate mechanisms? Even if we see differences in confidence level post-treatment, can we really say it’s because of hormonal changes?
As I reported a few days ago, Dan Dennett has withdrawn from a Templeton-sponsored symposium at the World Science Festival that had religious overtones (note the question at issue below: did humans arrive in incremental steps or in “one giant leap”?):
Now Dan’s withdrawal has been picked up by the Religion News Service in a piece called “Philosopher says ‘no; to major science forum over Templeton funding.”
Here are a few choice quotes from the piece:
Dennett said he objects to Templeton sponsorship because he finds some of the projects they fund scientifically questionable. He is one of several scientists and philosophers who have refused to take Templeton money in the past, including physicist Sean Carroll and philosopher Massimo Pigliucci.
In a 2013 article in Slate, Carroll wrote: “Any time respectable scientists take money from Templeton, they lend their respectability — even if only implicitly — to the idea that science and religion are just different paths to the same ultimate truth. That’s not something I want to do.”
For Dennett, the issues were a bit different.
“I would be very happy to have the Templeton Foundation sponsor research on religion and science,” he said in a phone interview from Spain, where he is lecturing. “But what they are doing now is sponsoring some very fine science with no strings attached and then using their sponsorship of that to try and win prestige for other projects that are not in the same league.”
He pointed specifically to the Darwin Festival held in Cambridge, England, in 2009, which was also funded in part by Templeton. He wrote that some of the presentations there were “full of earnest gobbledegook.”
Check out the link to the gobbledegook stuff; Dan’s report on the Cambridge meetings, which he let me publish, is hilarious. And I love this quote from Dan:
“I compare it to an art collector who spends a lot of money on excellent art and then has a show with a few pieces by his brother,” Dennett said this week. “It’s trying to elevate the prestige of his brother by having them in the same room with a Cezanne and a Monet.”
Religion: the art collector’s brother!
I’ve had my differences with Dan over memes and, of course, free will, and with Massimo over many things, including the ambit of science. But I want to publicly applaud both of them, and also Official Website Physicist™ Sean Carroll, for putting principle over publicity and emoluments.
And from the Templeton side:
Earl Whipple, vice president of communications and public affairs for Templeton, said the organization invests in individuals with “an attitude of humility and open-mindedness.”
“Discoveries often result from competing ideas, rigorous scholarship, and civil dialogue, not from the inhibition or limitation of debate,” he said.
There’s the old “humility” trope, always found in conjunction with faith. As for “competing ideas,” when has Templeton ever set up a syposium about science/religion issues without stacking it with its own flacks?
For some laughs, read the comments under the Religion News Services’ piece.
Reader Donn Ingle from South Africa has sent photos before (see here), but here’s a new batch. Donn specializes in his local flora, and sends the following information:
I live in Betty’s Bay on (not quite) the southern tip of Africa. I’ve been taking arty pics of my surrounds for a couple of years. I’m not trained in any science, so the nouns (see file names) of things may well be off. I am more than fortunate to be here among the fynbos and I hope you enjoy the photos. [JAC: The captions are Donn’s file names]:
Agathosma piculata (“buchu”) with blue fly:
Baboon mother looking out:
Bee in Protea repens palace:
Brunia albiflora inflorescence:
Chrysanthemoides monilifera (“bietou”) with bee:
Fresh colours of an unknown Protea:
Finally, Stephen Barnard sent a closeup of a desert cottontail (Sylvilagus audubonii) with the caption:
Sometimes you have the wrong lens so you make do.
When I first saw today’s Google Doodle, with the initial animation of a goose nurturing its young, I thought it must be Konrad Lorenz’s birthday. But then the cheetahs and rabbits appeared, and I knew Lorenz didn’t study those. Then I had my “aha” moment: it’s Mother’s Day.
What I like about the Doodle is its depiction of a connection between maternal behavior in taxonomically diverse species which, to me, means a commonality of natural selection promoting that behavior: kin selection. Behaviors promoting the nuture of relatives also promote the replication of genes fostering those behaviors. So, though I don’t know if Google intended it, there’s an evolutionary lesson.
Here’s the animated Doodle:
My own mother is long gone, but for those of you who still have one, or are mothers yourself, remember that the celebration of Mother’s Day is also a celebration of the power of evolution to mold behavior!
It’s Ceiling Cat’s Day and also Mother’s Day, and although neither Hili nor I are mothers, we are both children of Ceiling Cat, so all praise to Hir. My back continues to improve, it’s cold in Chicago; and it’s early. But we must be about our Father’s work. Meanwhile in Dobrzyn, the cat/d*g dialogue is enigmatic
Cyrus: New times are coming.
Hili: Do you think they will come from that direction?
In Polish:
Cyrus: Idą nowe czasy.
Hili; Myślisz, że przyjdą z tej strony?
The dialogue reminds me of Sherlock Holmes’s interchange with Dr. Watson in the story His Last Bow. Both men are standing on the cliffs of Dover, looking east, and Holmes foresees War One. Watson, befuddled, thinks that Holmes is talking about the actual wind:
“There’s an east wind coming, Watson.”
“I think not, Holmes. It is very warm.”
“Good old Watson! You are the one fixed point in a changing age. There’s an east wind coming all the same, such a wind as never blew on England yet. It will be cold and bitter, Watson, and a good many of us may wither before its blast. But it’s God’s own wind none the less, and a cleaner, better, stronger land will lie in the sunshine when the storm has cleared.”
It’s in Alabama (of course), and in a bill introduced by a Republican (of course). To quote Pete Seeger, “When will they ever learn?” Well, the tactic of passing bills urging “critical examination of science”, a euphemism for “being able to give creationist alternatives to evolution,” has worked, at least in Louisiana and Tennessee, which have passed similar bills. It’s a sneaky and clever tactic, but it’s also a last resort, and it’s not going to allow creationism or intelligent design to be taught legally. (They are, of course, being snuck in under the radar by religious teachers.)
As Alabama.com reports, the new bill was introduced by Republican representative Mack Butler, a god-fearin’, flag-wavin’ True Amurcan who is, unfortunately, on the state House Education Policy committee:
Legislation that would allow Alabama educators to teach alternatives to mainstream scientific theories like evolution, the origins of life, global warming and human cloning was introduced late last month in the House of Representatives.
. . . The ACLU of Alabama is already speaking out against the bill introduced by Rep. Mack Butler, R-Rainbow City. The bill has yet to be considered in committee.
“This is a thinly-veiled attempt to open the door to religious fanatics who don’t believe in evolution, climate change or other scientifically-based teaching in our schools,” said Susan Watson, executive director of the ACLU of Alabama. “It also opens Alabama to costly litigation that it just cannot afford.”
Well, we’ll see about that “costly litigation.” I’m not sure whether the Tennessee and Louisiana bills have yet been contested or litigated, for they’re “stealth” bills that, on the face of it, look innocuous. But their purpose is insidious. You can find the pdf of Butler’s Alabama Bill HB592 here. Below are the critical parts; note that Butler shows his hand by emphasizing the areas that might be seen as “controversial” (my emphasis):
Section 1. (a) The Legislature finds that an important purpose of science education is to inform students about scientific evidence and to help students develop critical thinking skills necessary to become intelligent, productive, and scientifically informed citizens. The teaching of some scientific subjects required to be taught under the curriculum framework developed by the State Board of Education may cause debate and disputation including, but not limited to, biological evolution, the chemical origins of life, and human cloning. Some teachers may be unsure of the expectation 19 concerning how they should present information when debate and disputation occur on these subjects.
(b) The State Board of Education, local boards of 22 education, public school superintendents, public school 23 principals, public school administrators, and public school teachers shall endeavor to create an environment within K-12 25 public schools that encourages students to explore scientific questions, learn about scientific evidence, develop critical thinking skills, and respond appropriately and respectfully to differences of opinion about scientific subjects required to be taught under the curriculum framework developed by the State Board of Education.
Here’s the bit where they say that teachers can’t be penalized for pushing critical or “alternative” views’ (aka, creationism):
. . . (d) Neither the State Board of Education nor any local board of education, public school superintendent, public school principal, or public school administrator shall prohibit any teacher of a public school from helping students understand, analyze, critique, and review in an objective manner the scientific strengths and scientific weaknesses of all existing scientific theories covered in the course being taught within the curriculum framework developed by the State 19 Board of Education.
Finally, there’s the obligatory but disingenuous claim that this has ABSOLUTELY NOTHING TO DO WITH RELIGION:
(e) This section only protects the teaching of scientific information, and shall not be construed to promote any religious doctrine, promote discrimination for or against a particular set of religious beliefs or promote discrimination for or against a religion.
If you look in the dictionary under “lie,” you’ll find the sentence above.
The Raw Story gives some details of Butler’s history (he is a Baptist, of course), as well as a selection of his Facebook posts. This one is a doozy:
If the intent of the bill isn’t transparent from what Butler says, you need new glasses (or a new brain). In fact, this shows clearly that the bill violates two of the three prongs of the Lemon Test, which mandates that any such bill must have a purely secular purpose as well as not serve to advance religion. Does anybody think that Butler’s purpose is secular, or that he’s indifferent about pushing Christian views?
Here’s one more contribution by Brother Butler:
Tell it, Mack! And God bless America!
h/t: Terence
Well, at least in this small field:
Before there are any reviews, I will now predict the two most common tactics the faithful (and faitheists) will use to go after it (both of which are discussed and dismissed in the book, but the petulant won’t notice).
1. “Coyne attacks a caricature of religion, one that nobody believes in. It’s typical New Atheist strawmanning.” This is what I call the Eagleton/Armstrong Gambit. People who use it need to get out more.
2. “Coyne assumes that religion is largely based on factual propositions: beliefs about what is true. That’s an old-fashioned and obsolete version of religion. Religion isn’t about truths; it’s about community and morality and feeling.” Sadly, the data show that while religion does have these other functions, it’s simply not the case that truth is irrelevant. Even theologians (the honest ones) admit that without an underpinning of beliefs about what’s really true about the universe, religion crumbles. Where would Christianity be if adherents thought that Jesus’s divinity, crucifixion, and resurrection were just a fictitious but convenient framework on which to hang their emotions? Would Mormons wear their sacred underwear if they knew Joseph Smith was really a con man who fabricated those plates? Do the Sophisticated Critics really believe that if Muslims knew for certain that Muhammed didn’t get the Qur’an from the mouth of God, via an angel, but made it up himself, that Islam would have the sway it does? Get serious.
Bring ’em on (but take a number)!
And feel free to add your own predictions. After all, the reactions to books that criticize religion are almost 100% predictable.