The phrase comes from “mastodont,” which the Oxford English Dictionary tells us comes from
French mastodonte (Cuvier 1806, in Ann. du muséum d’hist. nat. de Paris8 270) < masto- + -odonte, with regards to the nipple-like tubercles current in pairs on the crowns of the molar tooth.
Maybe these nipple-like objects got here from Amazons,
< Latin Amazon, < Greek Ἀμαζών, -όνα; defined by the Greeks < ἀ priv. + μαζ-ός a breast (in reference to the fable that they destroyed the appropriate breast in order to not intervene with using the bow), however most likely pop. etym. of an unknown overseas phrase.
And naturally they do not name it Go Ogle for nothing.