Researchers claim Neanderthals were NOT a sub-species of modern humans
Researchers have identified new evidence supporting the growing belief that Neanderthals were a distinct species separate from modern humans (Homo sapiens), and not a subspecies of modern humans. The study also found that the Neanderthal nasal complex was not adaptively inferior to that of modern humans, and that the Neanderthals' extinction was likely due to competition from modern humans and not an inability of the Neanderthal nose to process a colder and drier climate, as has been previously suggested.
Samuel Márquez, PhD, associate professor and co-discipline director of gross anatomy in SUNY Downstate's Department of Cell Biology, and his team of specialists published their findings on the Neanderthal nasal complex in the November issue of The Anatomical Record .
They argue that studies of the Neanderthal nose, which have spanned over a century and a half, have been approaching this anatomical enigma from the wrong perspective. Previous work has compared Neanderthal nasal dimensions to modern human populations such as the Inuit and modern Europeans, whose nasal complexes are adapted to cold and temperate climates.
However, the current study joins a growing body of evidence that the upper respiratory tracts of this extinct group functioned via a different set of rules as a result of a separate evolutionary history and overall cranial bauplan (bodyplan), resulting in a mosaic of features not found among any population of Homo sapiens. Thus Dr. Márquez and his team of paleoanthropologists, comparative anatomists, and an otolaryngologist have contributed to the understanding of two of the most controversial topics in paleoanthropology -- were Neanderthals a different species from modern humans and which aspects of their cranial morphology evolved as adaptations to cold stress.
"The strategy was to have a comprehensive examination of the nasal region of diverse modern human population groups and then compare the data with the fossil evidence. We used traditional morphometrics, geometric morphometric methodology based on 3D coordinate data, and CT imaging," Dr. Márquez explained.
Neanderthal skull discovered in 1908 at La Chapelle-aux-Saints ( Wikipedia). The new study found distinctive differences between the Neanderthal and Homo sapiens nasal complex.
Co-author William Lawson, MD, DDS, vice-chair and the Eugen Grabscheid research professor of otolaryngology and director of the Paleorhinology Laboratory of the Icahn School of Medicine at Mount Sinai, notes that the external nasal aperture of the Neanderthals approximates some modern human populations but that their midfacial prognathism (protrusion of the midface) is startlingly different. That difference is one of a number of traits suggesting an evolutionary development distinct from that of modern humans. Dr. Lawson's conclusion is predicated upon nearly four decades of clinical practice, in which he has seen over 7,000 patients representing a rich diversity of human nasal anatomy.
Jeffrey T. Laitman, co-author and Professor at the Icahn School of Medicine and director of the Center for Anatomy and Functional Morphology states that this article is a significant contribution to the question of Neanderthal cold adaptation in the nasal region.
"The strength of this new research lies in its taking the totality of the Neanderthal nasal complex into account, rather than looking at a single feature. By looking at the complete morphological pattern, we can conclude that Neanderthals are our close relatives, but they are not us," said Dr. Laitman.
Ian Tattersall, PhD, emeritus curator of the Division of Anthropology at the American Museum of Natural History, an expert on Neanderthal anatomy and functional morphology who did not participate in this study, stated, "Márquez and colleagues have carried out a most provocative and intriguing investigation of a very significant complex in the Neanderthal skull that has all too frequently been overlooked." Dr. Tattersall hopes that "with luck, this research will stimulate future research demonstrating once and for all that Homo neanderthalensis deserves a distinctive identity of its own."
Featured image: Wax model of a Neanderthal. Credit: Erich Ferdinand / flickr
SUNY Downstate Medical Center. "Were Neanderthals a sub-species of modern humans? New research says no." ScienceDaily. 18 November 2014.
Journal Reference :
Samuel Márquez, Anthony S. Pagano, Eric Delson, William Lawson, Jeffrey T. Laitman. The Nasal Complex of Neanderthals: An Entry Portal to their Place in Human Ancestry . The Anatomical Record, 2014; 297 (11): 2121 DOI: 10.1002/ar.23040