Bonus points to the researcher, in announcing findings that intelligent people have better sperm, who said "This does not mean that men who prefer Play-Doh to Plato always have poor sperm: the relationship we found was marginal". I've a feeling that line has been getting a workout before it was picked up on the BBC. Nevertheless, it is clever.
The results themselves are unnerving - I'm not suggesting they're wrong, merely saying that once a 'biological' link is established, suggesting that 'nature' thinks smart people are more worthy of reproducing, it's easy to imagine scary conclusions being drawn.
I really need a tin foil hat to wear when I write this stuff.
I completely understand the concerns about what could follow from "nature prefers smarter people," but isn't something like this pretty much undeniable from an evolutionary perspective. "Smart" would have be defined somehow more specifically, with specific survival related advantages, but that shouldn't be too hard.
I think the only surprise here is that nature's evolutionary preference might be expressed in reproductive biology and not just in survival rates of reproducing adults.