O le Evolution Series o se laina o locomotives diesel na fausia e GE Transportation Systems (lea e umia nei e Wabtec), na muai fuafuaina e fetaui ma le US EPA's Tier 2 locomotive emissions standards na amata faamamaluina i le 2005. O le laina o le sui tuusao i le GE Dash 9 Fa'asologa. O iunite muamua a'o le'i gaosia na fausia i le 2003. Evolution Series locomotives ua fa'apipi'iina i le AC po'o le DC traction motors, e fa'atatau i le mana'o o le tagata fa'atau. O lo'o fa'aola uma i le afi GEGEVO.[4]

O le Evolution Series na faaigoaina o se tasi o le "10 Locomotives That Changed Railroading" e Trains Magazine ma na o le pau lea o le faasologa o locomotive na faalauiloa ina ua mavae le 1972 e aofia ai i lena lisi.[5]

O locomotives Evolution Series o nisi ia o locomotives sili ona fa'atau atu ma sili ona manuia i le tala fa'asolopito o le Iunaite Setete.

O locomotives o loʻo faʻapipiʻiina i Nathan Airchime K5HL pu, faʻatasi ai ma le fesuiaʻiga 2 faʻatulagaina, faia ai se K5HLR2. O pu e fa'amau i tua ma le logo e 2 e fa'asaga i luma ma logo e 4 e fa'asaga i tua. O locomotives uma e faʻaogaina nei pu, sei vagana ai le ET23DCM ma locomotives faavaomalo.