Elephants aggressive?

Schowalter-Hay, Ethan. "What Are the Causes of Aggression in Elephants?" EHow. Demand Media, 20 June 2011. Web. 18 Apr. 2013.

http://www.ehow.com/info_8619521_causes-aggression-elephants.html

        Elephants aren’t aggressive creatures unless they have a reason to be. Unless they’re a male going through Musth and have high doses of testosterone going through their body making them aggressive. Otherwise the only times an elephant will be aggressive is if they feel threatened by a person or something, or if there’s some sort of social tension in their herd. Elephants are naturally very defensive because they are always on the lookout for lions, hyenas, or tigers trying to take their young as a meal. Some examples of social strife might be if a male is going through Musth and gets aggressive with a bull (elder male) to earn some kind of dominance role in the herd. It’s said that male elephants fight for dominance from a young age. You can tell an elephant is upset by its ears, they will stiffen them right up and cocks there head up then shake their head back and forth. Also, an elephant might charge a predator or person to scare them, or swing its trunk in the person or predators direction. Moral of the story, don’t mess with an elephant because their size and weight is also a con for any person or predator that upsets them.