How to overcome the problem of modeling respiration departing from bony structures

DE AZEVEDO, S.; GONZÁLEZ, M.F.; CINTAS, C.; RAMALLO, V.; QUINTO-SÁNCHEZ, M.; MÁRQUEZ, F.; HÜNEMEIER, T.; PASCHETTA, C.; RUDERMAN, A.; NAVARRO, P.; PAZOS, B.A.; DE CERQUEIRA, C. C. SILVA; VELAN, O.; RAMÍREZ-ROZZI, F.; CALVO, N.; CASTRO, H.G.; PAZ, R.R.; GONZÁLEZ-JOSE, R.

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA

NATL ACAD SCIENCES

Año: 2018 vol. 115 p. 4739 - 4740

0027-8424

Evteev and Heuze´ (1) state that there is no evidencesupporting that Chinese, Japanese, and Korean populationsexhibit cold-adaptation features. However, severalfacial traits present in these groups were previouslyinterpreted as cold-climate adaptations (2?9). For instance,a composite sample that included Chinese,Japanese, and Korean individuals showed internal nasalvariation compatible with theoretical expectationsfor cold climate adaptations (9). It is also noteworthythat we applied computational fluid dynamics (CFD)analyses that directly test for differences in the internalnasal mucosa, making irrelevant any prior differenceamong cold- versus warm-evolved populations. Suchpotential prior differences are also irrelevant in the contextof Lande?s test, which departs from random evolutionas a null hypothesis.Further, the statement that there are no differencesbetween northeastern Asian (NEA) and southwesternEuropean (SWE) (1) is incorrect:We reported significantMahalanobis distances (figure 1D of ref. 10), observableeven when the morphospace is dominated by the twoNeanderthals that occupy an extreme position, thusblurring differences between SWE and NEA.Regarding contextual information, the human sampleis composed of 21 females and 17 males, with anaverage age of 54.9 y. Note that we provided morerelevant information on the population origin of thesamples in our study?s SI Appendix (10).Evteev and Heuze´ (1) also question the selection ofreference specimens used in the reconstruction of theNeanderthal tract. Note that the selected individualsfall near their group-specific centroid in the morphospacedefined by the first two principal components infigure 1B of ref. 10, and the distant placement of Neanderthalsin the morphospace ensures that any differencebetween the human references has nosignificant effects on the final warped reconstructionof the Neanderthal tract (ref. 10, p. 5).Regarding the interpretation of our CFD results,we report a key role of the anterior-most part ofthe nose as a key structure for air conditioning andthat the NEA model achieves faster air uniformity,followed by the Neanderthal model. In no way do wedenominate such results as ?huge differences? asstated by Evteev and Heuze´ (1). We are well awareof the fluctuating and unstable nature of the mucosa.However, reconstruction of 3D mucosa modelsbased on a single individual, even when prone toerror due to noising factors, provides a complementarypicture to the classical one, based on the morestable (but not so relevant in terms of air conditioning)osseous traits.The authors (1) also underestimate our covariationanalysis, and refer to a previous work that found weakcovariation between the anterior and posterior nasalairways (11). However, Bastir and Rosas (11) did notplace internal landmarks at the lateral walls of the cavity,and their focus was exclusively on modern humans.On the contrary, we aimed to validate thewarping approach using a broader phylogeneticframework (10). In this sense, we detected a very significantpattern of covariation among different parts ofthe nose, as well as its stability across different clades: modernhumans; chimpanzees; and Macaca, an outgroup that includes acold-adapted species.We do think that, considering the data available, our sample achieves the criteria needed to create a proper reconstruction ofthe Neanderthal tract.