A de-evolution of the typical White male, into a retarded, mongoloid animal that runs straight on Coors and weed. Most real Motocrossers hate Bros because they all suck at riding but say that they don't. Some Bros can be classified as wiggers, which is odd because they are extremely racist. They drive 20" lifted trucks that never see dirt yet boast about how they did 8 backflips at Glamis. They like to start stuff with people for no reason on the way you look even though they look about ten times as gay as you could ever dream of making yourself look. Their slutty jizz jar female followers known as "Brohos" are dumb bimbos that just want to get fucked and have some sense of an identity.
My girlfriend was real cool until she started wearing SoCal shit and started hanging out with a couple Bros and wanted me to start shopping at No Fear, so I dumped her slutty ass.
I might also mention that about 4 of my really good friends degenerated into Bros a couple years ago and they now work in either commercial construction or a No Fear store... If your friends start showing signs of Bro degeneratingness, it would be best to put them down.