Yuanmou Man inhabited a mixed environment featuring grassland, bushland, marshland, and forest dominated by pine and alder.

The Institute of Vertebrate Paleontology and Paleoanthropology funded further excavation of the site, and reported 16 stone tools, of which six were found in situ and 10 nearby.

Because the formation is faulted (several rock masses have been displaced), biostratigraphy (dating an area based on animal remains) of the human-bearing layer is impossible.

In 1977, with a much larger sample size, Cheng Guoliang and colleagues instead placed the area during the Olduvai subchron, and dated it to 1.64–1.63 million years ago.

In 1979, Li Renwei and Lin Daxing measured the alloisoleucine/isoleucine protein ratio in animal bones and produced a date of 0.8 million years ago for the Yuanmou Man.

In 1998, R. Grün and colleagues, using electron spin resonance dating on 14 horse and rhino teeth, calculated an interval of 1.6–1.1 million years ago.

[5] In 2002, Masayuki Hyodo and colleagues, using palaeomagnetism, reported a date of 0.7 million years ago near the Matuyama–Brunhes geomagnetic boundary during the Middle Pleistocene.

It was part of a major expansion of H. erectus across Asia, the species extending from 40°N in Xiaochangliang to 7°S in Java, and inhabiting temperate grassland to tropical woodland.

The Yuanmou Man is only slightly younger than the Dmanisi hominins from the Caucasus, 1.77–1.75 million years old, who are the oldest fossil evidence of human emigration out of Africa.

Yuanmou Man could also indicate humans dispersed from south to north across China, but there are too few other well-constrained early Chinese sites to test this hypothesis.

[9] The teeth were formally described in 1973 by Chinese palaeoanthropologist Hu Chengzhi, who identified it as a new subspecies of Homo erectus, distinct from and much more archaic than the Middle Pleistocene Peking Man, H. ("Sinanthropus") e. pekinensis, from Beijing.

[1][2] In 1985, Chinese palaeoanthropologist Wu Rukang said that few authors in the field recognise H. e. yuanmouensis as valid, with most favouring there having been only one subspecies of H. erectus which inhabited China.

[2][8] Similar anatomy is also exhibited in Late Pleistocene archaic human specimens from Xujiayao, China; and Neanderthals from Krapina, Croatia.

The mammals are: the chalicothere Nestoritherium; the deer Cervocerus ultimus, Procapreolus stenosis, Paracervulus attenuatus, Rusa yunnanensis, Cervus stehlini, Muntiacus lacustris, M. nanus, gazelle, and chital; cattle; pigs; the elephant Stegodon; rhino; the giant short-faced hyaena Pachycrocuta brevirostris licenti; pika; and small rodents.

Fossil pollen deposits on the Yuanmou teeth and artefacts can largely be assigned to herbaceous plants, pine, and alder.

These bones and similarly aged burnt remnants from various parts of the world are now considered to be the products of natural wildfires, making it unlikely that the Peking Man was using fire.