In these ads, we see the linking of men’s sexuality with animals. This is a popular trope in American culture, used to excuse all kinds of bad behavior on men’s part.
In this Trojan ad, we see that men who don’t use condoms are pigs, while men who do are “evolved.” (At least they’re encouraging men not to be pigs.) Also, that if a woman isn’t interested in you, just get a condom and she’ll totally change her mind:
In this ad from Australia, sent in by Daniel G., men actually grow antlers in order to contest over a cute blonde who, of course, goes with the winner as if she’s genetically programmed to find the man with the biggest, eh em, antlers most attractive.
(For a minute I thought that last was about learning to play for the other team. Alas.)
See also this post in which a husband is a jackass.