Standards going up play a big role in all of this, in my opinion. To clarify what I mean, could you consider track running or swimming? In these and other physi

Standards going up play a big role in all of this, in my opinion. To clarify what I mean, could you consider track running or swimming? In these and other physical sports, it is evident that world records keep climbing year after year, to the now much-noted point that the best high schoolers typically are "faster" than the world best for a few decades ago. Obviously nothing has happened on an evolutionary scale in the timespan of a century, so what explains it? It's almost like how a goldfish will grow to the size of its bowl-- new humans will grow to and exceed the standards of the last generation, it's just human nature. It's a bit trickier to apply the principle to creative pursuits than it is to physical ones, but I think it may help explain why students could appear cleverer over time without anything changing biologically. To give one final example that doesn't involve sports. I am a trumpet player and am pretty familiar with the phenomenon that the best of the best in trumpet playing goes up as the decades go by. Rafael Mendez, Maynard Ferguson, etc. will forever be considered as the all time great virtuosoes, but the cold hard fact is that their technical abilities were only good in light of the time-- exceeded by hundreds if not thousands of the best trumpet players today. It's all about context.