LiveScience published a list of the most interesting discoveries about human nature in the past year. Topping the list is how people tend to segregate themselves based on political leanings; another describes research findings that heroes and psychopaths have more in common than previously thought.
Other studies that made the cut:
-- Women who take the pill are more drawn to men with less-masculine faces, and during peak periods of fertility, women like the presumably musky, manly smell of "testosterone-rich" men.
-- Five distinct types of boredom have been identified.
-- A 19-year Boston University study concluded that more guns are, in fact, associated with a greater number of deaths from guns. (You might think it would be unnecessary for science to provide evidence of this, but as we know, conservatives like to vehemently deny any correlation between the two.)
-- Valley Girllike "uptalk" (When everything said sounds like a question? And every sentence ends in a higher tone of voice?) is spreading around the world.
To find out more about 2013 research, including why you think you understand your friends but don't, really, check out Tanya Lewis's LiveScience post.