Every batch of sperm represents an opportunity for genetic typos - called de novo mutations - to be passed on. A 20-year-old man and woman will each pass on about 20 de novo mutations to a baby they conceive. By the time the couple is 40, a woman's total has remained at 20, while a man's has jumped to 65 - and it keeps climbing from there.

There are a lot of obstacles in the way of our understanding animal intelligence - not the least being that we can't even agree whether nonhuman species are conscious. We accept that chimps and dolphins experience awareness; we like to think dogs and cats do. But what about mice and newts? What about a fly? Is anything going on there at all?

I grew up in a suburb of Baltimore with an extremely high concentration of Jewish families - where the Levys and Cohens in the high school yearbook went on for pages, where I could count far more temples than I ever could churches. Anti-Semitism, in our cultural biodome, was mostly an abstract concept.

The families of many athletes - incensed at the sports leagues and hoping to make games safer overall - are increasingly making the brains of players who die prematurely and suspiciously available for study. Some athletes are even making the bequest themselves.

When you learn conflict-resolution skills in the playroom, you then practice them on the playground, and that in turn stays with you. If you have a combative sibling or a physically intimidating, older sibling, you learn a lot about how to deal with situations like that later in life. If you're an older sibling and you have a younger sibling who needs mentoring or is afraid of the dark, you develop nurturing and empathic skills that you wouldn't otherwise have.

Vaccines save lives; fear endangers them. It's a simple message parents need to keep hearing.

Photography is about freezing a moment in time; McGinley's is about freezing a stage in a lifetime.