I cannot believe I haven’t written you about this until now. Today’s post is about scale in transportation, and one of the enduring lessons of my first graduate degree in botany.
Coming out of school in Atlanta, I was fired up to do urban landscape ecology. Every school and faculty I talked to had never heard those three words in the same paragraph, much less concatenated. So I wound up doing landscape ecology for my thesis project. Our study plot was a great design by Dr. Nick Haddad at UGA (now at NCSU) designed to test the effect of landscape connectivity and distance on movement of species. The landscapes were 128m on-a-side squares of clear cuts connected or not-connected to other clear cuts of the same size by a 32 meter wide clear cut corridor connecting two of the larger clear cuts. It also turned out to be a great way to test edge effect, since these were clear cuts after all. Each “triad” of patches let us look at the effect of connection on lizards, butterflies, birds, mammals, and bees. Or specifically, Passionflower pollen, on the backs of Carpenter bees.
I won’t go into the details of everything we tried to get good data out of these bees, but I’ll cut to the chase. I can regale you with colorful tales of graduate suffering, insect personalities, and personal misadventure in the comments if you’d like. Ask me anything.
Carpenter bee movements are a great way to study Passionflower pollination. Xylocopa are the primary pollinator species in the Southeast of Passiflora, and their bodies are just the right size/hairiness to pick up pollen from anthers in the morning and deposit it on stigmas in the afternoon. The problem with carpenter bees is that they are strong fliers. Nearly an inch long, they have no problem flying a mile or more in one day. This was a problem for an experimental landscape with a maximum corridor distance of 384 meters. We spent the first two summers figuring out that the landscape of our design was not the landscape of Carpenter bees. I had to figure out how to get reasonable data out of these bees, or give up on graduate school entirely. So I found a landscape over five times as large in the same area to work with, and worked my third summer to get data out of it.
This little parable is a great metaphor for the problem with transportation in America, and why we don’t walk as much as we could. The landscape we have built for almost a century is for vehicles that move, weigh, and need over ten times as much as walkers or bikers. New walkable places in America must contend with the fact that a lot of America is populated by these vehicles operating at a different scale entirely. Walking is an afterthought between parking lot and store, supplied by loading dock, fed by trucks. Little wonder that we barely walk anymore. We don’t build at that scale anymore.
Apologies for the hurried ending, but I have to make a journey that would have taken the founding fathers a week. In traffic, natch.