My cruise last week gave me the chance to see my Mom, along with my late father's surviving siblings. It also gave me a preview of coming attractions in my own life. (If you're already thinking of your own Mom here, consider getting her something like this, from Stevens Glass Chalet.)

It was very cheering. Uncle John turned 80, but remains tall, elegant, cheerful, marvelous, despite having lost his bride of nearly 60 years a few months ago. Dorothy is still his baby sister, giving him a four-foot high copy of a picture taken of him, in his infantry uniform, in Switzerland, on leave, shortly after V-E day, young and joyful and heroic. As he is today.

Then there was my Mom, still a young girl in many ways. She came to the ship in a wheelchair, but appeared on her own two feet at the cruise's formal night, and regaled us with stories far into the evening, in a bar on the top of the ship.

Little did I realize, but I was seeing the secret of civilization.

Two University of Michigan anthropologists, Rachel Caspari and Sang-Hee Lee, have correlated an increase in the number of older skeletons starting 30,000 years ago with the organization of real civilized societies.

The trend led to population expansion, and "cultural innovations that are associated with modernity," the researchers say. It also strengthened social relationships and kinship bonds, as grandparents educated extended families.

Great job, Mom.