We live on a competitive planet. From sports to academics, the urge to achieve, and surpass others, is strong within us. How did we get like this?

Curiosity contributor Susan Sherwood looks at competition itself, including whether we ARE, in fact, competitive.

First, must we accept the premise that humans are competitive? Life scientists and social scientists don’t always agree. One supporting argument is that, in an evolutionary sense, competition is adaptive. Our ancient ancestors had to compete for resources; the most adept survived. Indeed, when Homo sapiens spread from Africa they dominated the remaining Neanderthals and Homo erectus and were the only survivors. So, from the first, humans were in competition for their very existence.

There’s also a connection between hormones and competitiveness. After a sports competition, male winners have increased testosterone levels, while in losers it’s reduced [source: Bryner]. A 2002 study investigated the relatively unexplored area of hormones and female competitors, finding that levels of testosterone rose while the players were psyching up for a match. Levels during the game remained high, regardless of which team led [source: Bateup, et al].

There are also related personality variables. People with low self-esteem may escalate their urge toward competitiveness when anxious, in an attempt to re-establish self-confidence. Jealous people, meanwhile, might eschew cooperation, turning (often unnecessarily) to competition to meet emotional, social and financial needs. Pathological states such as sociopathy, for their part, are partially defined by the need to outshine others and achieve individual success [source: Greenburg].

However, some scientists find the dog-eat-dog portrayal of humans faulty. Critics believe our behavior is far more sophisticated. Researchers from Washington University found that, among all types of primates, aggressive behavior (including competing) usually accounts for less than one percent of daily social interactions. Friendly behavior is actually much more the norm.

A primatologist from Emory University named Frans de Waal argues that mammals are social animals that exhibit significant empathy. They are naturally inclined to develop emotional connections with others. This is especially true of females, who react innately to infants’ emotional behaviors such as crying for food. Over time, this has extended to sensitivity toward others [source: Fitzpatrick].

Everywhere there are examples of competition: elections, reality television, sporting events. But so are examples of human empathy: charity, disaster relief, friendship and universal health care.