Diprothomo platensis: a hominid from Buenos Aires?

Workers excavating a dry dock in Buenos Aires (Argentina) in 1896 found a human skull, allegedly in a Pre-Ensenadan stratum, a deposit dated one to one and a half million years old, eleven metres below the level of the Rio de la Plata. The Argentine palaeontologist Florentino Ameghino (1854-1911) gave it the scientific name Diprothomo platensis; however, re-examination by the American anthropologist Aleš Hrdlička (1869-1943) a short time later found the cranial capacity to be within the range of modern Homo sapiens and he rejected the new species. There are two problems with the discovery if we follow the conventional view: anatomically modern humans did not exist a million years ago and there were no humans in the Americas before about 35,000 years ago (to accept a controversially early date for their arrival in the western hemisphere).

As with Reck’s skull from Tanzania, there is no indication that the skull fragment was actually embedded in an undisturbed geological deposit. Although Diprothomo platensis appears regularly on creationist websites and in Forbidden Archeology, it has generally been consigned to the dustbin of history, where it remains an exhibit to the errors of previous generations of palaeoanthropologists. Irina Podgorny has written an interesting paper on Florentino Ameghino’s contributions to South American anthropology and his highly eccentric views on human evolution. Her analysis of his “craniorientor’, a device used to prove to his satisfaction that the Buenos Aires skull was an early hominid and not Homo sapiens should be read by everyone who wants to promote these supposedly anomalous human remains.