: one that goes before
It seems this word is most commonly used in reference to the Homo ANTECESSOR, an extinct human subspecies dating back 1.2 million to 800,000 years. The first fossils were discovered in the mid-1990's at the Gran Dolina cave site in the Sierra de Atapuerca region of Burgos, Spain. This site is known to be the oldest of hominid-fossil-bearing sites in Europe, and hence the H.A. are now thought to be the earliest specimens of human remains on the European continent, pre-dating the Homo Heidelbergensis, and prompting revisions of the "human family tree."
The most interesting feature about these early fossils is the presence of distinct cut marks on various bones, indicative of dismemberment. The marks match those on faunal specimens, suggesting the hominid's responsibility in the act of cutting. While this could make them ANTECESSORS to leatherface, archeologists believe they were cannibals.
Above you will find a model of a female Homo ANTECESSOR digging for human brains, courtesy of the Ibeas Museum in Burgos. She looks to the audience, as though to say, "Yeah? And?"