Can you please give the references for these studies?

IMHO the articel might have got the facts quite right - knowing Kant or C++ or earning a lot of money does not not really help to spread your genes. But the conclusion - help, we have a problem - relys on a very selfish point of view: Evolution does not go into a direction I like, therefore it does not go on at all. Maybe the blind watchmakers (thanks to R. Dawkins) point of view is more helpful: Better genes are defined as genes which stayed around for a long time. Any other objective - humans should get smarter, richer etc. - is wishful thinking. If you like any other special optimization goal, you have to use something else but evolution. Or, better, forget about finding something else - things might be O.K. just the way they are... Oh, by the way, mankind might have enough room for improvement in the phenotype :-)