On our long driving trips during this week's travels, we heard several Hot New Insights on the various radio programs (mainly on the BBC) that we listened to, to pass away the miles. Among other things, we learned of a few culinary discoveries that merited media attention:
- First, humans became smart because they cooked their food.
- Second, we like salt, sugar, and corn syrup because these tastes evolved when we were hunter-gatherers 10,000 years ago (then agriculture was invented), though these foods were hard to get back then. We now prefer to overdose on junk food because of our hunter gatherer 'supra instincts' -- but we can train ourselves to like leafy greens and other (organic) vegetables within two weeks.
- Third, breast-feeding is good for infants and should be encouraged in a global campaign, led by a famous model. It may be a surprise, we guess, that humans evolved doing this!
But for a few details (most of point #2, e.g.), these culinary discoveries may be true. But they could be just this generation's punditry, taken seriously by hungry not-very-critical journals and media. How might we know?
One way is to look back at was said in the past. If you go back a generation or more, and look at what scientists and the media were saying then, it's easy to judge many of our forebears in science to have been childlike in their simple naivety.
A second way to evaluate what passes for deep evolutionary wisdom in the mediasphere is to think about what is being said for at least, say, a nanosecond. Point #1 depends on early hominids having control over fire very early in our evolution, for example, and they'd have to have been eating predominantly cooked foods for it to be enough of an evolutionary force. Our brains were already getting bigger before we invented the Weber barbecuer.
The idea that our hunger for McFoods reflects our ancestral dietary history is odd if our deep 'instinctive' cravings really can be changed in two short weeks. We may have biological hungers for such things 'because' they were not particularly easy to come by in our past, but if they were rare then they must not have been vital to our success. And hunger for such things predates humans. The fact that advertisers play on our innate hungers need not have any particular evolutionary importance. And if new cravings are so easily learned, who's to say that our McFood cravings weren't taught to us in a few short weeks when we were young?
The idea that breast-feeding is beneficial is news to the general public only if it's something that's not been in the media recently, in a society that spurns and forgets about anything that's more than a month or two old. The same arguments were hyped all over the place by the same pop-culture media only a generation ago (but old books don't make profits for today's authors or professors). Advocacy by many authors, the La Leche League, the internal campaign against Nestle's, and many others were common and advocated for the same reasons, within memory.
The rediscovery of breast-feeding may indeed be based on important points about breast-feeding, but it is not comforting to see how comparably confidently these points were advocated as newly deep insights in the not-so-distant past.
The important point is to be critical judges, especially when evolutionary just-so stories are being told. This is not only because they're mostly just that, just-so stories that are not confirmable if they even stand up to critical examination.
All precedent suggests that today's punditry is going to look naive and silly a generation from now (except those things that will be breathlessly asserted again, as if they'd never been said before). And if we can't tell what will look silly, or we can know that most of what we say and believe will look silly, why do we take any of it seriously today?
A more general question is how we can know which things of those that all of us assert today have any depth of truth or sticking power? Surely some of what we conjecture about the past is true, but almost as surely, we have a devil of a time knowing what it is, and self-interest and gullibility allow us to accept much that we should be more circumspect about.
There are often if not usually aspects of middle-class short-sightedness in these kinds of statements, too. Fast food may be making people overweight, but it is important to remember that even if this leads to disease later in life, most people didn't live that long in our not-so-idyllic hunter-gatherer ancestry. We might legitimately wish to live even longer and more healthfully, but junk food is not 'poison' in evolutionary perspective. It's actually rather nutritious--if we were doing something other than sitting on our duffs watching mindless television all day long.....