So what’s this we’ve heard all our lives about one year of human life equaling seven of a dog’s? Marilyn vos Savant, the genius who writes the “Ask Marilyn” column for the Sunday mag, Parade, sets us straight, although we can’t figure it out even with a calculator, because she’s the genius and we’re, um, not. If humans’ and dogs’ rates of aging were similar, she says, then a one-year-old dog would be like a seven-year-old child and a 10-year-old dog would be akin to a 70-year-old senior. But actually, “experts” concur that a one-year-old dog is more like a 15-year-old human and a 10-year-old dog is more like a 56-year-old. When a dog reaches 13, she says with just a hint of hilarity, it would be eligible for Social Security.