2nd one is just naive and reminds me a little about the introduction scene in #Idiocrazy where an intelligent couple (high IQ) was to stupid to want to have children and blame the economy for it. Later he died from a heart attack when he attempted to masturbate to artificially impregnate his wife who died later in hope to find the "right one".

Meanwhile, stupid (lower IQ) were intelligent enough to make children (by accident sometimes, broken condoms or forgotten pills).

Keynote of the movie: Stupid fucks good! The others are okay, last one doesn't feel so much convincing (taken in a snowy landscape).