I was recently reminded about an urban environment that I have known for more than twenty years — that cities are living and evolving organisms. Neighborhoods change composition as children grow up and adults change jobs or retire. Bars, restaurants, shops, and hangouts come and go. Immigrants and transplants pick new and upcoming areas. It’s part of a constant cycle of change and renewal. It’s sad sometimes to consider the cultural losses along the way. But, at the high level, it’s a critical part of how cities avoid ossification and retain authenticity.