Each year, it’s fun to celebrate birthdays. If we’re not sure of someone’s age, we can always check their birth certificate. But can any reliable methods determine the age of an object without a historical record?
As the old saying goes, dogs are man’s best friend. Dogs perform many useful tasks—from hunting to security to helping people with disabilities. Most of us would agree that we’re just glad they’re part of the family! Where did dogs come from? How can we explain the tremendous variety of dog breeds?