[redthrowaway]

>Selection of dog breeds for intelligence (German Shepherds, Jack Russell terriers, Poodles vs eg King Charles Cavaliers, Corgis) seems to have produced a large gap but it took a long time - dogs have been domesticated for ~5,000 years.

Dogs have been domesticated since the dawn of civilization (and probably before), but those specific breeds are relatively new. GSDs are just over a century old, Jack Russells slightly older, poodles several hundred years old and Corgis positively ancient at almost 1000. Note, too, that intelligence was not the sole quality they were bred for. The Russian Silver Fox is a great example of the massive changes that can occur in only a few generations if artificial selection for a single trait is performed.

That said, I agree with the gist of your argument: 15 pts of Iq per generation seems ludicrous.