American Fighters Surname Origons (UFC)

I've missed a few obvious ones out like Lesnar and Sherk because i cannot seem to find any confimation of where those names are from, i'd bet on...

Source: http://www.mmaforum.com/ufc/98079-american-fighters-surname-origons-ufc.html

Eric Butterbean Esch Efrain Escudero Rashad Evans Urijah Faber