Sir

Russell Ciochon, in his Essay 'The mystery ape of Pleistocene Asia' (Nature 459, 910–911; 2009), makes passing reference to the Late Miocene ape Lufengpithecus, which is known from Lufeng in the Chinese province of Yunnan. Ciochon then immediately discounts the significance of Lufengpithecus because “the age was wrong”. This assumption, however, leads up a blind alley.

Ciochon and his colleagues initially ascribed the teeth of a fossil found at Longgupo — in neighbouring Sichuan province — to Homo (W. Huang et al. Nature 378, 275–278; 1995). Now he proposes a “mystery ape” to account for the Longgupo specimen and other similar material he recently observed in southern China.

He dismisses the possibility that these remains belong to descendants of Lufengpithecus. Yet it seems very likely that they do. The fauna recovered from Lufeng and Yuanmou, also in Yunnan — which have produced abundant fossils of Lufengpithecus — have also produced faunal remains directly ancestral to the Stegodon–Ailuropoda fauna of Pleistocene southern China (Z. Q. He and L. P. Jia (eds) Yuanmou Hominoid Fauna; Yunnan Science and Technology, 1997).

As both the Pleistocene apes Gigantopithecus and Pongo of southern China assuredly had Miocene antecedents, then so did Ciochon's mystery ape. Given their morphological and dimensional similarities, there is every reason to suspect that the mystery ape is none other than a descendant of Lufengpithecus, as originally proposed (for example, D. A. Etler et al. Hum. Evol. 16, 1–12; 2001). Mystery solved.

see also Mystery ape: a call for taxonomic rigour.