What does an average human look like?

It turns out Wikipedians have had a very detailed discussion on the topic. Their current selection on the article for “Human” is of a southeast Asian man and woman, both farmers, who are not wealthy but not destitute, either. Given population demographics, that’s probably about right.

But what’s interesting to me is the background—a rolling landscape, partially forested, that’s a mix of pastoral and agricultural uses. Does this image also represent the average human habitat? 

San Gabriel Valley, California

Jennifer Medina, reporting for the New York Times:

“This is kind of ground zero for a new immigrant America,” said Daniel Ichinose, a demographer at the Asian Pacific American Legal Center. “You have people speaking Mandarin and Vietnamese and Spanish all living together and facing many common challenges.”

Illegal Districts Dot New Delhi as City Swells

Jim Yardley, reporting for the New York Times:

India is often demarcated along lines of caste or class. But many of India’s rapidly growing cities are also delineated by the legal status of where people live. For years, as migrants have poured into Indian cities in search of work and opportunity, illegal settlements, often slums, have sprung up in the absence of available, affordable low-income or even middle-class housing. Many of these settlements have grown into bustling districts more populous than many American cities, yet lacking amenities and legal protections, and residents face the perpetual threat of eviction.

Who Rules the Street in Cairo? The Residents Who Build It

Michael Kimmelman, reporting for the New York Times:

A struggle — and also a race — pits the forces of collapse against the halting emergence of a new urban class, born in the aftermath of the revolution. Egyptians have long been experts at fending for themselves in a top-down system where the president ruled by fiat and the government was unaccountable. But now they must improvise as never before. This means that Egyptians are figuring out anew how they relate to one another and to the city they have always occupied without quite fully owning — figuring out how to create that city for themselves, politically and socially, as well as with bricks and mortar.

When Algae on the Exterior Is a Good Thing

David Wallis, reporting for the New York Times:

A new apartment complex in Hamburg, Germany, intends to generate heat, as well as revenue, from growing the micro-organism. The five-story Bio Intelligent Quotient (B.I.Q.) building, which was expected to become fully operational on Wednesday, has a high-tech facade that looks like a cross between a Mondrian painting and a terrarium but is actually a vertical algae farm.

I don’t even know what to think about this one.

An Architectural Reflection of George W. Bush

Henry Grabar, writing for the Atlantic Cities:

The Bushes are passionate about sustainable architecture, and the Center has reflective roofs, solar panels, and the infrastructure to harvest rainwater. It is LEED Platinum-certified. 

Seriously? I’m not doubting Grabar’s reporting on this, but I’m struggling to square the Bushes’ “passions” with his actions while president.

Secrets of Cloud Formation, Revealed in the Amazon

Adrianne Appel, reporting for NOVA Next:

There is so much particulate matter in the air in heavily developed regions like North America and Europe—mostly from pollutants—that scientists are unable to easily study which particles impact cloud formation and how. The “cleanest” atmosphere in rural North America, for example, has 2,000 or more particles per cubic centimeter; most are from pollution. Those numbers soar near cities, where densities can be as high as 10,000 to 100,000 particles per cubic centimeter. “There is too much noise in the atmosphere,” Martin says.

There are a few places where particulate signals are quieter.

One guess where one of those is.

How the Decline of the Traditional Workplace Is Changing Our Cities

Emily Badger, writing at the Atlantic Cities:

For decades, cities have reflected the neat separation of work and home, with residences in one part of town, offices and industry in another, and infrastructure (highways, parking garages, hub-and-spoke transit systems) built to help connect us between the two around what has been for many people a 9-to-5 work day. But what happens when more people start to work outside of offices, or really anywhere – at all times?

The internet's image problem

Alex Wild wrote about image sharing (without attribution or concern for copyright) run rampant at his blog, Compound Eye. The object of his ire is I Fucking Love Science, a keen Facebook page that’s become a hub of science outreach on the web. It’s a great page, but many, many images are posted there daily without attribution, and Elise Andrews, who runs the page, makes money off the venture.

But I’d argue that that’s just the tip of the iceberg. Andrews is an independent operator, and her transgressions are minor and, as Wild rightly points out, could be easily remedied. The bigger problem is that large, corporate sites, often with millions of dollars in revenue or deep pockets lined with venture capital, have the same blasé attitudes about creator’s rights. They frequently misappropriate copyrighted images to generate traffic and ad impressions on their sites, sending paltry traffic to the original site. I’m talking about BuzzFeed, Gizmodo, Popular Science, Business Insider, and others. I’m speaking from experience here. They’ve all taken my infographics, without permission, and posted them to their sites, in some cases without even proper attribution or a link.

I’ll grant that the internet is still a bit the Wild West, but that doesn’t mean it should be a free-for-all. Even Huffington Post writers have gotten in trouble for “over aggregation” of written posts. (Sad, in a way, because I’m sure the writer was pressured to do exactly that.) But with images, there seem to be fewer qualms. What makes images different?

I’ll leave you with a few words from Ed Yong, who chimed in last night on Twitter: “If someone posted my writing on their site w/o link or credit, I’d be fucking outraged. This is not different.”

More reasons to stop putting trees on skyscrapers

Bosco Verticale

Robert Krulwich, disagreeing with me:

Two residential towers, dense with trees, will have their official opening later this year in downtown Milan, Italy, near the Porta Garibaldi railroad station. (The image is not a photograph, but an architect’s rendering. The towers are built and the trees are going in right now.) I love this. I think these towers are gorgeous. Milan is a very polluted town; these trees will cleanse the air, pumping out oxygen and greening the cityscape. I think cities one day could look like mountain vistas; I’m enthralled.

But I am not Tim De Chant, tree lover, blogger, critic, who says this won’t work. All these trees, he thinks, are about to be dead. He recently posted an essay on his Per Square Mile blog, aimed at architects. He called it, “Can we please stop drawing trees on top of skyscrapers?” He thinks builders know squat about trees. I hope he’s wrong.

I know I seem like Buzz Killington to a lot of architects—and non-architects, Krulwich included—but that wasn’t my point…entirely. To me, trees atop buildings have become an architectural crutch, a way to make your building feel sustainable without necessarily being so. And that’s a charitable assessment. Here’s how I really feel—trees on skyscrapers are a distraction from rampant development and deforestation. They’re trees for the rich and no one else. They’re the soma in architecture’s brave new world of “sustainable” development.

In reality, trees on skyscrapers will likely be anything but sustainable. Structures built to support trees need to be over-engineered compared with their abiotic equivalents—trees are heavy, so is dirt (multiply so when wet), and so are watering systems required to keep them alive. If those trees are to have a chance on these windy precipices, their planters had better be deep, which further compounds problems raised in the previous sentence. A skyscraper that’s built to support trees will require more concrete, more steel, more of anything structural. That’s a lot of carbon, not to mention other resources, spent simply hoisting vegetation dozens of stories up, probably more than will ever be recouped in the trees’ lifetimes.

Bosco Verticale, the oft, and often only, cited example of a tower to be built with trees on top, is expected to cost $85 million. Stefano Boeri, the architect, estimates adding trees to the design pushed up construction costs about 5 percent. (No word on maintenance costs.) Whether that’s true or not, we’ll have to take his word for it. If we do, that means they will spend $4.25 million to put 2.5 acres—one hectare—of forest onto the side of a building.

Now, let’s say we take that money and resuscitate the region’s natural habitat.¹ Average costs run about $500 per acre for reforestation in U.S. national forests, with a top end of about $2,000 per acre. Let’s assume the worst. That means that with $4.25 million, you could restore 2,125 acres, or about 860 hectares, of forest. That’s 860 times more forest than is plastered on the side of Bosco Verticale. At the least. If restoration costs come in at the low end, about $200 per acre, it could be as high as 8,600 times more.

Then there’s the ecological value of each. Bosco Verticale will be home to a few birds (most of which will live in the city regardless) and some invertebrates, but not much else. It’ll also require massive human inputs—water, fertilizer, tending, and replacement. I covered the first of those three in my previous essay, so I’ll just elaborate on the last point here, replacement. Let’s say trees on a skyscraper will live for an average of 20 years—a generous assumption given that more than 50 percent of street trees, which are exposed to more benign conditions, die after just 10 years—what will we have gained? A skyscraper that needs an overhaul every 20 years.

A real forest, on the other hand, can replace itself. It can also support hundreds, even thousands of species, even in the middle of the city. A survey of the 315-hectare Central Park, for example, found over 800 species. Near Milan, at Parco Regionale di Montevecchia e della Valle del Curone, there nearly on it’s 2,350 hectares. Biodiversity is just one measure. These forests also purify water, maintain nutrient cycles, and don’t require much in the way of maintenance (if any).

Here’s an alternate plan: Instead of planting trees on buildings, let’s focus on preserving and restoring places that already have, or desperately need, trees. Boeri and I agree on the importance of the latter. Bosco Verticale is the first stage of Boeri’s larger plan, one that includes preservation and restoration of existing land.² Bravo. It’s clear that Boeri understands the big picture, that to make a truly sustainable city, you have to incorporate ecosystem function on a broad scale.

We still disagree on the value of trees on skyscrapers: he, and Krulwich, see them as an inspiration; I see them as a distraction and potential liability—what if the Bosco Verticale becomes a brown eyesore, turning people off to his larger vision? I’d love it if Bosco Verticale and other proposed arboreal skyscrapers were sustainable and successful.³ Who wouldn’t want to live in a city full of tree towers? But I just can’t make a case for it. Plant physiology tells me that the trees, if they do survive, will require constant and costly maintenance throughout their short, brutal lives. Finance tells me that the money required to afforest a building would be more effectively used for restoration and preservation. And my gut tells me there are more equitable ways to give people trees, not just to those who can afford it.

  1. You could also plant street trees or reserve more land for parks, both laudable and equitable uses.
  2. Among the proposals is a greenbelt around the city. They’ll be great parks, but won’t do much to contain the city.
  3. Really, Robert, I do!


Roman, Lara. 2006. Trends in street tree survival, Philadelphia, PA. Master’s thesis.

Gorte, Ross W. 2009. U.S. Tree Planting for Carbon Sequestration. Congressional Research Service R40562.

Illustration of Bosco Verticale.

Related posts:

Can we please stop drawing trees on top of skyscrapers?

Urban trees reveal income inequality

Income inequality, as seen from space

Converting city buses into showers for the homeless

Christina Farr, reporting for Venture Beat:

San Francisco is teeming with tech entrepreneurs who want to save the world but who’ll pass by the homeless person on the street without a second glance. Doniece Sandoval, a Bay Area tech entrepreneur, is not one of them. Her latest trick? Turning retired city buses into mobile showers for the homeless. The initiative, known as Lava Mae, is a response to a desperate need in the city. According to the most recent count, more than 6,500 homeless people sleep on the street or in shelters in San Francisco, and there are only eight shower facilities specifically available to the homeless, and most of these have just one or two stalls and aren’t open every day.

Boston Marathon

I was at the finish line an hour before the bombs went off. We passed it on our way to meet a friend who had just finished the race. Thankfully, he’s fast. He ran the 26.2-mile course in just over 2 hours and 40 minutes. By the time the explosions occurred, we were safe at home, sitting on the couch. I can’t remember exactly how I heard the news—someone was browsing Twitter or Facebook, I think, and told the rest of us. We turned on the TV. Initially, I thought it was a gas explosion. It’s funny how your first instinct is to assume it was an accident. It’s distressing when you find out it wasn’t. It took a while for that to sink in.

Last night, my wife said yesterday felt like it was two days long. She’s right. Yesterday was two different days. One joyous and triumphant, the other heart-wrenching and tragic.

Mahogany’s Last Stand

Scott Wallace, writing for National Geographic:

The last stands of mahogany, as well as Spanish cedar, are now nearly all restricted to Indian lands, national parks, and territorial reserves set aside to protect isolated tribes. As a result, loggers are now taking aim at other canopy giants few of us have ever heard of—copaiba, ishpingo, shihuahuaco, capirona—which are finding their way into our homes as bedroom sets, cabinets, flooring, and patio decks. These lesser known varieties have even fewer protections than the more charismatic, pricier ones, like mahogany, but they’re often more crucial to forest ecosystems.

Remembering Life in Arcosanti

James McGirk reminisces about his time spent at Arcosanti:

In a similar sense, Arcosanti felt like an anachronism, a permanent representation of a different time and a different ideology. Walking through the domes felt like walking through ruins, rather than the white-hot center of architectural thought it ought to have been, and to many, always seemed so close to becoming. (The idea of arcology has always been touted as of crucial importance — just not yet.) Unlike New Delhi, which has blossomed since I lived there, Arcosanti was too rigid of a structure — literally, its physical plant couldn’t adapt, and figuratively, its social structure was too fixed — to contain the full spectrum of people a city needs to survive; not just high priests and acolytes, but entrepreneurs and rogues too.

Personal space in major cities

Andrew Bergmann’s take on population density in select cities around the world for CNN Money.

Clever, but his title is all wrong. Bergmann is measuring population density, not personal space. For example, do you count freeways and parking lots as your personal space? Probably not. To get at true personal space, he would have to calculate home sizes or something similar. 

One-third of U.S. rivers contaminated with ag runoff

China’s environmental degradation has gotten a lot of attention lately—remember the story about 16,000 dead pigs found in the river that supplies Shanghai’s drinking water? But American waterways aren’t faring too well, either. Scott Johnson at Ars Technica summarizes a recent EPA report that shows nearly one-third of U.S. rivers are too high in nitrogen and nearly 40 percent too high in phosphorous.