Mixed Breed isn't a breed but a label for dogs whose ancestry combines two or more breeds, or is unknown. They fill much of the adoptable dog population, and they run from compact terrier mixes under 20 pounds to shepherd, hound or retriever mixes over 70. Coat, color, ears and build can come from any branch of the family tree, so no two look quite alike.
Because ancestry varies, the dog in front of you tells you more than a guess about its parents. Look at size, energy, coat and how it handles people, other dogs and busy streets. In Brooklyn, where most days involve sidewalks, stairs and shared spaces, leash manners and calm around noise matter as much as size. Meeting a few dogs and choosing on personality tends to work better than choosing on looks.