The fact that people are unable to truly close their ears to unwelcome sounds is very maladaptive to modern times. Think about it: you can hold your nose (or breath) and smell/taste almost nothing. You can squeeze your eyes shut and experience pitch blackness. But even with ear plugs, head phones, closed doors, and sound-proofing, it's nearly impossible to achieve the equivalent in silence when there's noise around you that you want--nay, MUST--shut out. There used to be good reasons for this: we need to be able to hear a baby's cry, irksome as it is. We need to be able to hear predators skulking in the shadows. Or rival bands of nomads approaching in the night. But the course of human evolution simply has not caught up to the following:
1. The loud, obnoxious public conversations of strangers sharing their views on politics, religion, weather, or current events in close proximity to us (our own such conversations are fine, of course).
2. Car alarms (anyone's).
3. Beeping, buzzing, or singing toys and "books."
4. The raucous, nauseating sex of other people in an adjoining hotel room or neighboring apartment (our own raucous sex is fine, of course, and presumably not nearly as nauseating).
5. Other people's cell phone, e-mail, and text ring tones (our own are also fine, because we need them, obviously).
6. The whines and screeches of children (any children) in the midst of a tantrum about anything unrelated to imminent loss of life and/or limb.
7. Drum kits in your house (played by anyone).
8. More than 15 minutes of Zydeco music.
9. More than 30 seconds of a morning shock jock DJ.
10. More than five seconds of cable or network television news broadcasters and reporters delivering "news" and/or interacting with each other in any way.
11. Anything that comes out of Jim Carrey's or Adam Sandler's pie-hole.
12. Any song by Maroon 5.
Perhaps over time there will be enough horrible sounds in the world that human beings will evolve the ability to shut down their sense of hearing more effectively. For now, we're basically stuck listening to the guy in 23 C flirt with the flight attendant; receive 18 text messages (each one of which is announced by a high-pitched, double-chiming glass ping); and try to shmooze out a merger on his cell phone--all before the plane has even left the tarmac.
