The most surprising thing I learned today comes from the opening paragraph of a paper by Anne Case and Christina Paxson:

In late 19th Century Europe, adult height was attained at age 26.

This is just one reminder of how radically life has changed in the last 100 years. At least in the developed world, we have moved from a life of subsistence to a life of luxury.

The rest of the Case and Paxson paper, titled "Stature and Status: Height, Ability, and Labor Market Outcomes," is interesting, too. Dubner tangentially mentioned this paper in a post a while back, but I think it deserves even more discussion.

It is well documented that tall people tend to hold high-status jobs and earn high wages. There are many possible explanations for this: height is a useful job attribute for some reason; other people mistakenly think tall people are more intelligent than they really are; being tall in high school gives you the confidence to succeed in the work force; etc.

Case and Paxson suggest a completely new explanation for the link between height and high wages: taller people earn more because they are smarter on average. They document that, as early as age three (before schooling has had a chance to play a role), taller children perform significantly better on cognitive tests. These higher scores persist through childhood. I find their evidence pretty convincing — though this is not good news for my four year old son, who is currently in the 5th percentile for height, just like I was at his age.

It is not often that someone tackles a commonly-researched problem and is nonetheless able to offer a new and convincing alternative explanation. I offer them the highest compliment I can think of: I wish I had thought of that!