This really depends on your concept of "strong evolution". If that is jargon meant to refer to a conglomeration of changes that makes the organism different all over, I would agree. If we're just talking about this in terms of "Is it possible that something of critical importance could significantly change in a few generations?" then I say "Yes, it is possible." I assume you consider responsibility to be an important trait. Even if a change to the trait of responsibility alone may not qualify as "strong evolution" to you, would you say that it would be of critical importance to prevent humanity from losing the genes required for responsibility in even half it's population? In a world where 40% of the people get here by accident, and we can tell that a lot of their parents failed to use their contraceptives consistently, are you unconcerned that there could be a relationship between irresponsible use of birth control and irresponsible genes being reproduced more rapidly than responsible genes? [...] But today's situation is not the same. We have technologies now that could result in much more powerful unintended consequences just as it results in powerful intended ones. Birth control pills, for instance, didn't exist thousands of years ago. Our lives and environments are so different now (and are continuing to change rapidly) that we should not assume that our present and future selection pressures will match the potency of the selection pressures in the past. To do so would be to make an appeal to history.