Everyone knows what a bird is, right? If I ask my seven-year-old son what a bird is, he 'll respond with something like "a bird is an animal that has a spine, wings, two feet, hollow bones, and can......
Everyone knows what a bird is, right? If I ask my seven-year-old son what a bird is, he 'll respond with something like "a bird is an animal that has a spine, wings, two feet, hollow bones, and can......
