can be 10m or so I've read. I think the idea here is unbroken corridors of habitat through the city and suburbs. The highway metaphor only goes so far: no one

can be 10m or so I've read. I think the idea here is unbroken corridors of habitat through the city and suburbs. The highway metaphor only goes so far: no one thinks insects in quite the same way as freight trucks, but insects and wildlife have thrived for millions of years in continuous habitat, which we suddenly in the last 100 years have broken into tiny little chunks with huge barriers between them: mechanical, chemical, electromagnetic, etc. The result: extinction, and we are to blame. If we are smart, we will build these corridors everywhere, and link them to large wilderness parks.