Is biking in cities good for you?

Life presents us all with certain problems, one of them being how to move ourselves from place to place. I submit that if you live in a compact, congested city, there’s really only one sane solution: ride a bicycle. Biking is carbon-neutral, it’s efficient, it’s outdoors, it’s exercise, it’s free, it’s fun. It’s a win-win-win-win-win-win.

But as I’m dodging morning traffic on my way to work in Washington, DC, I do find myself wondering, am I just fucking crazy? Could the health benefits from bike commuting possibly outweigh the risk of getting flattened by some latte-swilling, texting SUV driver? And even if I avoid that fate, what about the longer-term effects of the exhaust fumes I’m sucking in with every breath?

Morning traffic into DC

Morning traffic into DC

Since I am a science writer, I feel compelled to try to answer such questions with data. So it was troubling to find that one of the few sources providing data on the risks of different modes of transport puts biking near the top in deaths per journeys, miles traveled, or time spent in transit (apparently based on a 15-year old British survey). Only motorcycling, which is essentially bicycling at the speed of car traffic, proved more dangerous. U.S. data from a similar time period and cited in this paper tell a similar story.

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The World’s Longest Conveyor Belt

Satellite image of the Bou Craa conveyor belt

The Bou Craa conveyor belt running through the arid Western Saharan terrain. Credit: Bing maps.

The longest conveyor belt in the world runs 61 miles from the hostile interior of Moroccan occupied Western Sahara to the port city of El-Aaiún. Open to gusty desert winds in many places, the belt’s precious white cargo is strewn across the dusty brown desert, marking  the Earth so profoundly that this massive machine’s outline can be seen from space.

Between around 100 and 55 million years ago, marine waters of the nascent and ever-widening Atlantic Ocean transgressed and regressed over this now dry land. These waters deposited thick muddy sediments containing the decaying tissue, bones, shells, and excrement of dead marine life that had collected and concentrated on the ocean floor over millions of years. As a result, this thick oozing mud, a complex mélange of fetid material, was rich in phosphorus.

Without phosphorus, life itself is not possible. It exists in all living things —in cells, in bones, indeed, even in DNA. For that reason, the mud that formed the hills of Western Sahara so many millions of years ago were full of phosphorus. Now, millions of years later, it is that same phosphorus that we extract from the Earth and load onto a conveyor belt. Read the rest of this entry »


To Squat, or To Sit: That Is the Question

Credit: Mark Buckawicki, Wikimedia Commons.

Credit: Mark Buckawicki, Wikimedia Commons.

Let me apologize in advance, this post is about poop. Or rather, pooping.

My college suitemates and I always get together every Halloween. This year, my friend Kathy hosted us at her apartment outside New York City, and I happened upon a very interesting contraption in her bathroom. I believe the correct term is squatty potty? A platform specifically designed for toilet users to perch upon it and, well, squat instead of sit. The device belonged to one of her roommates, and I have to say I found it both fascinating and hilarious.

Squatting has gained more of a following in recent years, as scientists become more interested in how our bodies cope with the sedentary lifestyle of industrialization. Of course, there are also millions of people around the world who squat out of necessity because they don’t have Western toilets. Doctors have been suggesting we squat instead of sit since the 1960s. Their rational? It’s just better or more natural for our physiology. Sitting, they say, puts the passage from the rectum to the anal canal at the wrong angle. A 2010 study published in the journal Lower Urinary Tract Systems suggests that squatting produced a 126° angle, compared a 100° angle when sitting. When one squats, the rectoanal angle is straighter, so pooping requires less effort.

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