Making sense of eastern Asian Late Quaternary hominin variability
Nature Communications volume 15, Article number: 9479 (2024 ) Cite this article
A greater degree of Late Quaternary hominin morphological variability is present in eastern Asia than previously assumed. Indeed, a number of distinct populations are present, some that now have new specific names: Homo floresiensis; H. luzonensis; H. longi; H. juluensis. With this piece, we describe the various groupings based on the current hominin fossil record of eastern Asia.
When compared to other paleontological disciplines, the field of Late Quaternary (~300,000–~50,000 years BP) paleoanthropology has lagged far behind in synthesizing the degree of morphological variability in the hominin fossil record. It is now evident that morphological diversity among Late Quaternary hominin fossils from eastern Asia (East and Southeast Asia all-inclusive) is greater than we (and most researchers) expected. Indeed, there are now a number of new eastern Asian hominin taxa that have been proposed over the past several years reflecting not only a growing hominin fossil record but a greater appreciation for the degree of complexity that is present. This hominin variability is likely the result of a combination of dispersals and introgression that occurred throughout the Late Quaternary, rather than a single dispersal and complete replacement event.
During the early stages of paleoanthropology, beginning in the latter part of the 1800’s, many fossils were assigned new species names. This may not be very surprising given how new the field was, how few fossils were known at the time, and importantly, how much morphological variability paleoanthropologists were aware of at the time. However, nowadays, paleoanthropologists tend to lump rather than split the Late Quaternary hominin fossils. In general, lumpers tend to emphasize similarities between fossils, focusing on intra-specific variation around a mean, while splitters emphasize differences in fossils, using these to identify different species1. This may be partially due to efforts by scientists beginning in the 1950s, particularly from discussions resulting from the 1950 Cold Spring Harbor Symposium, to be more conservative and lump hominin fossils into broader more inclusive categories. This latter push could be related to the realization that many of the earlier proposed distinct species in fact exhibit overlapping morphologies and lack the presence of unique traits that would clearly distinguish them into separate taxa2,3.
