Are Cyclists Destroying the Earth?

Karl T. Ulrich, a professor at the Wharton School of the University of Pennsylvania, has put forth a provocative theory. Traveling by bicycle, he argued in a recent paper, may cause more environmental harm than driving around in pollution-spewing, fossil-fuel-swallowing cars and sport utility vehicles.

How can this be? Bicyclists are healthier, he wrote, so they live longer. Over their lifetimes, they consume more energy than they save.

The New York Times