But these weren't insects; they were bikers!
Every Tuesday evening from April through October, scores of cyclists (who should probably not be called bikers but I couldn't resist the alliteration) skim along Reston's suburban thoroughfares. They zoom by so impossibly fast that all I sometimes catch of them is a blur of movement.
If I'm close enough (as I was night before last), I might pick up a bit of conversation or laughter, a few words out of context. But other than that, the cyclists scarcely seem human. It's as if person and bike have melded into one creature, a centaur of sorts. An impression that running in packs only reinforces.
After one or two packs swish by there is usually a straggler or two, huffing and puffing and bringing up the rear. They are the lucky ones. In it but not in it. Far enough away to know what they are part of.