Monday 31 March 2008

bad math

In the race for the most popular votes in the Democratic Party's presidential primary contests, Sen. Barack Obama's lead over Sen. Hillary Clinton is about 711,000 votes -- not including Florida or Michigan -- according to Real Clear Politics.

Of Sen. Obama's 711,000 popular-vote lead, 650,000 -- or more than 90% of the total margin -- comes from Sen. Obama's home state of Illinois, with 429,000 of that lead coming from his home base of Cook County.

That margin in Cook County represents almost 60% of Obama's total lead nationwide.

From instapundit.

Technically (other than an equivocation on the word 'margin'), the claim is true. But (using the same methodology) it is also true that 526,000 of his 711,000 vote lead (74%!) comes from Los Angeles County, California--a region Clinton won with 700,000 votes.

Could we please have some real analysis?

march 30 roundup

Some amoebas build houses.

10 science effects from Backreaction. I have personally experienced the Pauli Effect, and it isn't fun.

Urban futures. "For the first time in human history, more people now live in cities than don't." The forces of growth put great strain on cities around the world, and they manifest in very different ways. For example, "Mexico City has huge water supply and garbage disposal problems, inadequate transit, bad air quality, overcrowding and a culture of crime and corruption. Through it all, however, the city has never succumbed to its various crises, but carries on despite them." The scale and density of cities allows for many efficiencies, but "cities deliver 80 per cent of the services people expect in their daily lives on 25 per cent of tax revenues. As a result, public infrastructure is crumbling at every turn." With >50% of voters now living in cities, expect that to change fast.

Carl Zimmer says it's still possible to distinguish natural from artificial organisms, in part because scientists insist on inserting their names into the genetic code.

Sage Ross thinks the future of WikiPedia rests on news. Despite "a large--and mostly unmet--demand for internet discussion of news," "the top social news sites are only modestly popular, and there is still plenty of room for new players"--including Wikipedia, he thinks. The trouble is that the market for news commentary is saturated by hundreds of mediocre entrants. Ross predicts a "Wii moment" for Wikipedia. I have my doubts.

/. reports "MIT Review is taking a serious look at China's plans to prevent rain over... the Olympics. From the article: 'China's national weather-engineering program is also the world's largest, with approximately 1,500 weather modification professionals directing 30 aircraft and their crews, as well as 37,000 part-time workers — mostly peasant farmers — who are on call to blast away at clouds with 7,113 anti-aircraft guns and 4,991 rocket launchers.' They plan on demonstrating their ability to control the weather to the rest of the world, and expanding on their abilities in the future."

And finally, via Seed's Daily Zeitgeist:



Saturday 29 March 2008

saturday medley

Why have burglaries declined? Simple: supply and demand. "There's just too much on the street already."

The Bad Movie Science report card has many of the problems with any grading system: it is capricious, homogenizing, and plainly wrong.

Is war inevitable? Only when there's scarcity, pestilence, or gender, race, and class inequality. So, yes, then?

Need a jump-start on building your own procrastination aid blogroll? Check out shyftr's list of science blogs.

What is the key to success in science? Not beer. "After years of argument over the roles of factors like genius, sex and dumb luck, a new study shows that something entirely unexpected and considerably sudsier may be at play in determining the success or failure of scientists — beer." Fortunately, that study seems to have sample problems, and I'm going to go ahead and assume that the effect is illusory.

Friday 28 March 2008

Lost in the Sahel


The Sahel itself is a line.

The word means “shore” in Arabic, which implies a continental margin, a grand beginning and a final end. Stretching across northern Africa roughly along the 13th parallel, the Sahel divides—or unites, depending on your philosophical bent—the sands of the Sahara and Africa’s tropical forests. It is a belt of semiarid grassland that separates (or joins) Arabs and blacks, Muslims and Christians, nomads and farmers, a landscape of greens and a world of tans. Some 50 million of the world’s poorest, most disempowered, most forgotten people hang fiercely on to life there. And for 34 days in Darfur we joined their ranks.

and later

Even as the gunmen sauntered up, their hair matted in dreadlocks and their chests slung with small blackened things that looked like dried ears but which were Koranic amulets, we still hadn’t grasped that we had crossed a threshold where it no longer mattered what passport you carried, that you were young and loved, that your skin was supposedly not of a torturable color, or that you were a noncombatant. Words had lost all currency as words, and by the time the grinning teenager with the Kalashnikov reached for my door handle, we were condemned to live and die according to choices made by others. We had become truly Sahelian.

The Sahel is a line.

But it is also a crack in the heart—a tightrope, a brink, a ledge. See how its people walk: straight-backed on paths of red dust, placing one foot carefully before the other, as if balanced upon a knife edge. The Sahel is a bullet’s trajectory. It is the track of rains that fall but never touch the sand. It is a call to prayer and a call for your blood, and for me a desert road without end.

More from Paul Salopek

Stories like Salopek's are intriguing, not just for the artistry of his prose or the impressive setting in which his story takes place. Adventure reporters like Salopek (for what else should he be called?) fascinate by the claim of legitimacy they make. Far from gesturing toward the journalistic ideal of objective detachment, the journalist-qua-artist presents a very personal meditation on a complex situation. Fragmentary interviews and evocative descriptions of an alien landscape weave together with bread-and-butter facts and history to form a narrative elegy to those left behind by the homogenizing force of globalization but who are still with us.

What gives Salopek's words force is not simply the fact that he has been to a place I have not. It is that he expresses a sense of reverie, of thoughtful curiosity, that eludes the breathless reporting of the 24-hour news networks.

Sunday 23 March 2008

Sunday 16 March 2008

march 16 roundup - how to flirt in a burqa















  1. Better living through technology: a burqa that keeps you covered... but sends pictures of your face to bluetooth-enabled mobile devices.
  2. Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo” is a sentence with better grammar than most of mine.
  3. Coffee makes you more susceptible to arguments--but only good ones. "Is an increase [sic] understanding of other people's arguments worth the price of being more easily convinced?"
  4. Transportation Safety Administration has a blog. It's pretty good, and not at all written by trolls.
  5. W on art: hero, scalawag, what's the dif? "W does what he always does when he has no clue: he pulls something out of his ass and presents it as fact, and even becomes so convinced of its veracity that he completely disregards all evidence to the contrary."
  6. Online or offline, some neighborhoods are just better. "Outside.In, a website designed to gather and organize neighborhood news, published a list of “America’s Top 10 Bloggiest Neighborhoods.” What was striking (but perhaps not surprising) is that all were living examples of the kind of places Jacobs championed: Clinton Hill in Brooklyn, Portrero Hill in San Francisco, Shaw in Washington. If the physical form of a neighborhood is conducive to community, so is its virtual form."

Saturday 15 March 2008

stop teaching about science

Jonah Lehrer notes that while it is well-known that American schoolkids are bad at math, it's less well-known that "the steep decline in proficiency only starts when kids are taught algebra." Indeed, those who have success at algebra in middle school are twice as likely to graduate college. At fault, Lehrer says, is the abstract nature of algebra--unlike other subjects, which students can grasp by picturing or through physical acts like counting, algebra is by its nature "disconnected from the real world." But just because the subject is abstract doesn't mean its teaching has to follow suit. The lessons of John Dewey's philosophy of active learning may help.

I learned of Dewey's philosophy relatively recently, in 2003, when I worked for Ameri*Corps helping to found an Office of Community Engagement based on a higher education movement called "service-learning." The movement is based on the idea that the best way to get connect academic learning with practical benefits is to literally connect them, both through traditional internships and through new community service-based assignments--CPAs could offer free tax advice to the elderly, cooks could make rounds at soup kitchens, and so on. Dewey's part in this project for social change is on the educational side--his philosophy, and the experience gained from putting it into action at the Laboratoy School, undergirds one basic tenet of sevice-learning: learning happens by doing.
At the Laboratory School, Dewey was determined to make knowing and doing part of the same learning process. His mission was to "reinstate experience into education". The Laboratory students spent most of their day outside of the classroom, engaging in activities like sewing, carpentry and cooking.... But these activities weren't simply exercises in manual labor. Rather, they were demonstrations of "active learning". "If a child realizes the motive for acquiring a skill," Dewey argued, "he is helped in large measure to secure the skill. Books, the ability to read and bookish knowledge are, therefore, regarded as tools."

Take cooking. At the Laboratory School, the children were often responsible for preparing their own lunch. Dewey's insight was to build into this activity a wealth of related academics. Before students could boil an egg, they had to conduct experiments to determine the proper temperature at which to cook the egg. When they graduated to the preparation of more complicated dishes, the students had to weigh and measure the ingredients (arithmetic), understand the process of digestion (biology), analyze the process of cooking (chemistry and physics), and so on.

The secret, of course, was to sneak in the science. The knowledge had to seem indivisible from the lunch. "Absolutely no separation is made between the 'social' side of the work, its concern with people's activities and their mutual dependencies, and the 'science,' regard for physical facts and forces," Dewey wrote in 1899, in his best-selling pamphlet The School and Society. If the teaching was done right, the children wouldn't even realize they were being taught.

Lehrer has it right, except for the bit about "sneaking in" the science. In fact, this is precisely the "erroneous distinction" disembodied knowledge acquisition reinforces in students who grow up "believing that learning and doing were separate activities." Moreover, the secret isn't to "sneak in" the science. The secret is to unlearn all of the bad ways we come to know science.

If we take science to be the body of bookish knowledge collated by scientists, we're bound to be bored with science--and we're bound to resent it when science changes its collective mind about eggs or climate change. This is exactly why we need to change the way we educate people about science. Put another way, we need to stop educating people about science. Science education has to be more participatory and far less about repeating canned exemplar experiments for which we all know the expected result. Ultimately, science isn't something you can be told, it's something you have to do. If you're participating, you own it, and you'll defend it.

(For more on Dewey's philosophy, I recommend Louis Menand's The Metaphysical Club.)

Friday 14 March 2008

the link between video games and violence

Would you ban a video game where the objective is to find and kill Saddam Hussein? How about one where the objective is to recruit a suicide bomber to attack the President of the United States? Wafaa Bilal of Rensselaer Institute of Technology (Troy, NY) turned the former into the latter, a move that has--unsurprisingly--raised a few eyebrows.

(Let me point out, the picture on the left is a buddy of mine who talked to Bilal. NOT Bilal. So if you have a problem with Bilal, the man pictured is NOT him.)

At a Sanctuary for Independent Media event in Troy, Bilal defended the move as a political statement meant "to “hold up a mirror” to an American society which believes that such a game is perfectly fine when it is an American killing Iraqis, but which finds itself outside of its comfort zone when it’s the other way around."

Zac Miner, a sociologist friend of mine, was there:
During his speech, Bilal said that the idea for the game started with Quest for Saddam… in which the object is to find and kill Saddam Hussein. Apparently someone in Al Qaeda obtained a copy of the game, changed the skins of the soldiers and Saddam so that now the player is an Iraqi killing Americans and hunting George Bush [the so-called Night of Bush Capturing game].

[Bilal changed] the game from the Al Qaeda version so that instead of the player himself killing Bush, he now has to recruit someone else - in this case, a character skinned to look like Bilal himself… to become a suicide bomber and attack Bush. Bilial said that the point of this is to show the vulnerabilty of Iraqi citizens to recruitment for such purposes.

Unlike most of the event attendees, Zac played a demonstration version of the game in question. He concludes, "As a game, it wasn’t that good - the controls had some problems, the enemy AI wasn’t that great."

have space suit, will travel

British astronomers have agreed to beam a 30-second Doritos ad to a solar system 42 light years from Earth. (via /.) But what price should they advertise?

Paul Krugman's 1978 paper on interstellar trade, a self-described "serious analysis of a ridiculous subject, which is of course the opposite of what is usual in economics," takes on the basic dilemma presented by interstellar travel (near-light-speed). Time passes differently for the beings aboard the trading ship and the planets (the famous "Twin Paradox")--so by whose reference frame should interest be calculated in order to maintain consistent values? Krugman argues that "when trade takes place between two planets in a common inertial frame, the interest costs on goods in transit should be calculated using time measured by clocks in the common frame, and not by clocks in the frames of trading spacecraft." The device allowing this resolution is to suppose that a being could trade in goods or bonds, and because the price of bonds will be set planetside, so should be the price for goods.

This makes good sense, but it does have interesting implications. Consider two business plans:

1) exchange my cash for goods I'll trade on Trantor, get in a ship, go to Trantor, sell the goods for an Earth bond to mature upon my return, get back in my ship, return to Earth, and exchange my bond for cash.

2) exchange my cash for a bond. Wait a long time. Exchange my bond for cash.

There are two differences between these two scenarios: in (1) I take on risk but age only a little, and in (2) I take on less risk but age a lot. In fact, I propose that scenario (3) is effectively equivalent to scenario (1):

3) exchange my cash for a bond. Joyride around the galaxy for a while before returning to Earth. Exchange my bond for cash.

Guess which one I'll be taking to the bank?

Tuesday 11 March 2008

readymade sports

Many Canadians are familiar with The Red Green Show (and no, the man pictured here piloting a pumpkin is not Mr. Green, nor is his beard ironic. The pirate gnome, however, is.) (Ironic, not Mr. Green). Apparently, however, most people are under the impression that The Red Green Show is a comedy show and not a documentary. These people spend too much time in cities. Let me set the record straight. Back home, in Maine (which, let's face it, might as well be rural Canada), we understand Red on a more personal level. We tell heroic stories of how we once used duct tape to fix a broken trailer hitch, and made it all the way to Millinocket (going 35 on the highway) without losing the boat. We commiserate over the time we had to break into our own house because we locked ourselves out. And we know that the handyman only needs two tools: duct tape to keep things together, WD-40 to keep them apart.

But duct tape and cheap beer aren't the only things rural folk have in common. We also have sports. I don't mean NASCAR and hockey--they're great, but most of us simple folk can't afford the regulation equipment. No, I'm talking about pumpkin racing, lobster crate and lobster boat racing, mud running (or mud'n, the act of purposefully getting your truck aaalmost stuck), and power tool racing. The basic idea behind all of these events (and many more) is to turn the mundane or menial into a skilled competition. City-folk find such activities endlessly amusing, but hopelessly provincial. This is a mistake.

In exactly the way Duchamps turned a found object--a urinal--into 'art' by an act of designation, Mainers transform found activities into sports by acts of designation. Just like readymade art, the possibilities for readymade sports are effectively endless. As a rule, though, the potential of an activity to be elevated to sport-hood increases the more amusing the competition is likely to be to an audience.

Like all modern art, such events are all in good fun, of course, and self-mockery is half the point. But from this you should not jump to the conclusion that Mainers are irresponsible danger-seekers. Look again at the photographic lede: sure, this gentleman has affixed an outboard motor to a giant pumpkin. But he is wearing a lifejacket, as is the law for any vessel under 16 feet in Maine. Safety first.

What can a city like Toronto offer to compete with this?

Readymade sports have always been a part of Maine culture; we didn't need Marcel Duchamps to remind us to look at the objects around us with a playful eye. What distinguishes readymade sports from readymade art, if anything, is that readymade sports aren't a reaction to anything, and as such are missing the undercurrent of pretension that comes with rejecting four centuries of art theory. If we're looking for authenticity in art, we could do worse than to start looking for it at the Maine Pumpkin Festival.

Thanks to Zac for the pointer to this article in Maine's premier newspaper.

Saturday 8 March 2008

survivor: geology

A CBS "production manager happened to see a documentary on a volcanologist researching lava in Hawaii, and seeing the danger and excitement inherent in people smashing molten hot ‘magma’ with rock hammers, pitched the idea of a ‘geologist survivor-type’ show."

This from Tales from the Travels (via Evolving Thoughts). It may not be true, but let's not let facts get in the way of a good story. It's worth reading the whole thing, but I've picked out a few gems (hah!) for your bemusement:

The camera crew filmed the nine geologists bonding. The geologists were supplied with alchohol (a common strategy to loosen up the cast in reality TV), but the camera crew was surprised to notice that even after drinking gallons of the liquid, the geologists did not change their behavior, and continued talking in an obscure jargonized language about ‘bombs’, ‘breccia,’ and ‘lahars,’ none of which made for good reality TV.

Also, after listening to the volcanologist eagerly predict just how soon the volcano would blow, the camera-crew became extremely nervous and returned to the camp.

Finally, few of the scientists seemed to understand the concept of ‘voting off’ another member. After consulting a nearby university, the crew finally explained that the geologists were ‘competing for a GSA research grant.' This didn’t go well either, as the geologists pointed out that they didn’t have the time to write a research paper.
The second event, landing in a bush plane in upper Alaska, was a complete failure. None of the geologists were nervous at the idea, which destroyed the drama the crew was hoping for, and worse yet, no-one in the production crew was willing to accompany the geologists to the site, out of sheer terror.

CBS finally pulled the plug on the project in January of 2008, despite their fear that they might be sued for withdrawing the promise of a prize; however, none of the geologists sued, as they were still under the impression that they needed to publish a research paper to receive the money.

I doubt the story is true, but it does give me a good idea for a better reality show: the real 'contestants' would be the camera crew. Hire a bunch of actors and stunt players to pretend to be contestants, and have them do all sorts of crazy stuff that pits the crew against one another in a race to get the best shots. The producer would say things like, "you don't have to follow Jimbo into the snake pit, but if you do, you'll get overtime!"

Or maybe not.

John Wilkins says, "with appropriate substitutions, the same thing could be said of any academic," but I'm not so sure. If Survivor: Grad School were filmed in my department, for example, it's certainly true that there would be a lot of jargon-filled talk about historiography, epistemology, and ontology. It's probably also true that we would resist the idea of writing a paper, even for a large grant. The greatest risk the camera crew would run is getting lost in the stacks. Then again, getting a paper published is a bit of an adventure.

Friday 7 March 2008

a flood of new experimental data

via /.:
The [Glen Canyon] Dam is releasing four to five times its normal amount of water over the course of a three day artificial flood [in the Grand Canyon]. Scientists are conducting this massive experiment in order to document and better understand the complex relation of the aquatic habitats, natural floods, and the sediment they bring. Floods no longer bring sediment to these parts of the canyon as the Dam keeps it locked up and released in small, drawn out intervals. The Dam prevents the floods from bringing the sediments into replenish the sandbars and allow the river to maintain its warm, murky habitat rather than a cool, clear one. It is thought that this cool clear environment brought on by the dam is responsible for helping to extinguish 4 species of fish and push 2 more towards the brink. It is hoped that this terra-reformation experiment will positively impact the habitat and fish populations, warranting further artificial floods at an increased rate of every one to two years rather than the time span between the two previous floods and this one of 8 and 4 years.
It is delightful to hear that river managers are taking seriously the notion of planned extreme events.

One of the great joys of my early education was the scale river model in Mr. Lind's seventh grade science class. The table, perhaps one meter wide and two in length, with one end a hand or two higher than the other, was filled with gravelly sand. At the higher end, a faucet. At the lower, a bucket. Much like the ones used at the Waterways Experiment Station, this scale model demonstrates (or simulates) alluvial processes such as the formation of oxbows. This was one of my favorite experiences as a seventh grader, so I have a soft spot in my heart for WES.

More recently, I came across "The Art of Scientific Precision: River Research in the United States Army Corps of Engineers to 1945" by Martin Reuss [Technology and Culture 40.2 (1999) 292-323]. Reuss gives a good technical history of river research, contextualizing the scientific and technical challenges in a broader landscape of national politics and inter-agency scuffles. Though the work misses the larger context of culture, it still might help to fill in gaps left by other works. Reading at times like a biography of the Waterways Experiment Station, Reuss outlines the reasons for its inception, the details of its founding, and its relatively successful early history. The Army Corps of Engineers, the body responsible (along with the Bureau of Reclamation) for most large waterways engineering projects in the US, had a history of extraordinary successes and a few catastrophic and very public failures (Katrina is merely the most recent). The gap between theory and practice in hydraulic engineering was more of a chasm, and certain strong-willed bureaucrats clashed over what to do about it. The science was hard, the engineering involved too many variables, too much space, and too long a time span. "Hans Albert Einstein is reported to have said that his more famous father, Albert, was interested in river mechanics, but after careful consideration opted for the simpler aspects of physics" (322).

Many histories of new fields or agencies have an element of the "lone, neglected genius" and Reuss follows the script, which has the advantage of preventing him from slipping into technical inanity until the end of the paper. In any case, after a turf battle of sorts with the Bureau of Standards, a division of the Department of Commerce (which was interested in rivers for obvious reasons), the Waterways Experiment Station was formed (and words like "hydraulic," "research," and "laboratory" are missing from the title as a result of the politics).

One of the most fascinating lessons of ecology over the past century is the need for periodic medium-sized disruption to maintain overall system stability--and prevent catastrophe. Massive wildfires followed decades of fire control policy. Now foresters set small blazes to clear the forest floor of excess debris. Dammed rivers died without occasional floods to refresh their supply of nutrient-bearing silt and irregular shoals and sandbars. It stands to reason that smaller, planned floods will help to correct this deficit. The question now is, what else have we missed?

Thursday 6 March 2008

eat food. not too much. mostly plants

In case you can't tell from this, this, this, or this, I have kind of a thing for food. Mostly I like to eat it, but sometimes (on a full stomach) I read about food. Not whole books, in most cases. Reviews of books, or possibly a page or two from Harold McGee's On Food and Cooking: The Science and Lore of the Kitchen. With colleagues, I have even threatened to start a philosophy of food movement (one basted in experience, obviously). Michael Pollan has a thing for food, too.

Pollan came to Toronto Wednesday, and I was there to watch him perform. He read a bit from his new book, In Defense of Food, drew applause by claiming that the best food he's had on the book tour has been here in Toronto, and made clear, wide-ranging, and (nevertheless) fairly nuanced pronouncements about the state of food culture in the United States (and, by extension, Canada).

Pollan's narrative is simple, practiced and engaging: because the United States is a nation of immigrants, no single food culture has dominated the others, likely because what might have been the presumptive favorite (British food) is the worst of the available alternatives. What grew up in place of culture, then, was 'nutritionalism', a marketing tool to make processed food more appealing (New Cheesypoofs!* Now with beta-carotene! *real cheese flavor).

Thus his mantra: eat food. not too much. mostly plants. "Edible food-like substances," says Pollan, are not things your grandmother would recognize as food--and that's the problem. It is a miracle of modern science (or was that economics?) that we have 99-cent burgers, that 1 individual can produce food for 125 others, that high-status foods have such a low cost (when processed). Of course some of this is due to advances in scientific knowledge of agriculture and efficiencies of scale. But a large fraction is literally or effectively subsidized. The farm bill is part of the problem, as are costs externalized to the environment or shifted toward increased health-care costs as a result of unhealthy diet. These systematic problems are daunting, but at least some of them appear soluble.

A problem with the real food movement is that although purveyors form a lucrative niche, they are a niche market--namely, the very market that buys books by Michael Pollan. These middle-aged, middle-income middle-managers listen to CBC (or NPR in the States) in their hybrid cars as they drive to Whole Foods, where they use cloth bags to buy produce from the outside edges of the stores (avoiding the canned and boxed processed foods in the aisles). They have the disposable income with which to make that kind of lifestyle choice. The vast majority of North Americans have neither the cash nor the time to do more than feel guilty that they aren't making better choices for themselves or their children.

One big problem, says Pollan, is that people don't cook. Their lives are so unnecessarily harried that they don't have time to sit down to dinner, much less breakfast. Perhaps the nation needs better alarm clocks, he quips. The real trouble, he insists, is that we lack a cooking culture. If we didn't think of cooking as what one does on Thanksgiving or on Iron Chef, we might have a chance. But cooking has become an elite activity--or a chore. Chores, we make more efficient. Elite activities are leisure activities.

Will it ever be possible to walk into McDonald's, spend less than $5, and get a wholesome, balanced meal? Well, if it is possible to subsidize beef enough to get 99 cent burgers, then it is surely possible. It's a solution in search of a market. Are you buying it?

Saturday 1 March 2008

rapid fire march 1

Some items worth a second look, but not a whole entry:
  • parking roundup: "the cost of 'free' parking, up to $35,000 per space, is almost never passed along to the parking users."(related)
  • libertarians aren't "really the Nietzschean little sociopaths their arguments are always trapping them into claiming to be." If they weren't so busy being indignant, they might notice that "one of the nice things about being a liberal is that you never need to pretend that you're actually a barbaric hoodlum who only behaves civilly due to fear of punishment from the 101st Airborne."
  • Benjamin Cohen has a multi-part series about Objectivity, by Lorraine Daston and Peter Galison. I'll have a few things to say about it myself one day.
  • Speaking of Galison, he's compiled a very nice history of physics reading list for PhD general exams. It's worth a look.
  • boggle your mind with these color illusions.
  • John Wilkins says the recent revelation that "physical features of [Lapita Complex Polynesian] canoes that affected their reliability and efficiency were slower to evolve than the cultural features such as decorations" is unsurprising if we take cultural evolution to be analogous to sexual selection.