Well, if you're an anthropologist, these markings speak volumes. They indicate a trend among a certain group of cyclists to foreswear brakes and to slow their bicycles by skidding. There are also similar skidmark ganglions elsewhere on the bridge, generally before grade changes, bumps, or anywhere the path narrows a bit. This indicates that, when presented with an obstacle, these riders must lock up their rear wheels in order to adjust their speed.
One might wonder why a rider would opt to do this instead of installing a simple brake, especially when their cycling environment includes a bridge with a wooden surface which, at most times, is choked with camera-weilding tourists who stray into the bike lane like confused houseguests wander into closets while looking for the bathroom.
Well, I'm still trying to figure that last part out. I'm also wondering if the woman I got stuck behind the other day, straining to keep her shiny new brakeless IRO under control as she descended slowly and awkwardly towards Manhattan, decided at some point during her miserable-looking trip to spring another $20 for a front caliper. Perhaps she came to her senses. Or perhaps she didn't. Perhaps she enjoys looking like she's reeling in a marlin from the East River.
