Taxonomic differences in deciduous upper second molar crown outlines of Homo sapiens, Homo neanderthalensis and Homo erectus

Bailey, Shara E.; Benazzi, Stefano; Souday, Caroline; Astorino, Claudia; Paul, Kathleen S.; Hublin, Jean Jacques

doi:10.1016/j.jhevol.2014.02.008

Cited by 32 publications

(23 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recent studies have quantitatively supported the close morphological similarities between the two teeth both within and across hominin species. The same aspects of the M 1 that distinguish Neandertals and H. sapiens ( namely enlarged, protruding hypocone and metacone reduction) are found also in the dm 2 (Benazzi et al, ; Bailey et al, ). Likewise, the same features that differentiate Neandertals and H. sapiens M 1 crown outlines (buccolingual distal expansion vs. reduction, and convex vs. straight lingual outline shape (Benazzi et al, ) are found also in the in the crown and cervical outlines of dm 2 s (Benazzi et al, ).…”

Section: Measured Crown Areas (Mm2) Of Lower Dm2 and M1 In Matched Inmentioning

confidence: 75%

“…But even then, if three‐dimensional (3D) models are available, cervical outlines can provide taxonomically informative information (Benazzi et al, ). For example, cervical and crown outline shapes of the dm 1 and dm 2 have been shown to strongly discriminate between Homo neanderthalensis (hereafter, Neandertals) and H. sapiens (Souday, ; Benazzi, ; Bailey et al, ). Moreover, the shape of the dm 2 of H. sapiens and Neandertals are likely both derived relative to the ancestral condition but in different ways, with H. erectus exhibiting a more intermediate and likely ancestral form (Bailey et al, ).…”

Section: Measured Crown Areas (Mm2) Of Lower Dm2 and M1 In Matched Inmentioning

confidence: 99%

See 1 more Smart Citation

Allometry, merism, and tooth shape of the lower second deciduous molar and first permanent molar

Bailey

Benazzi

Buti

et al. 2015

American J Phys Anthropol

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Measured Crown Areas (Mm2) Of Lower Dm2 and M1 In Matched Inmentioning

confidence: 75%

Section: Measured Crown Areas (Mm2) Of Lower Dm2 and M1 In Matched Inmentioning

confidence: 99%

Allometry, merism, and tooth shape of the lower second deciduous molar and first permanent molar

Bailey

Benazzi

Buti

et al. 2015

American J Phys Anthropol

Self Cite

View full text Add to dashboard Cite

show abstract

“…Furthermore, differential wear may affect occlusal and crown manual outlines (Benazzi et al 2012;Bailey et al 2016). Nevertheless, as has been shown by others, the Neandertals are distinct from Holocene humans in the shape of the post-canine teeth (Benazzi et al 2011a, b;2012;Bailey et al 2014;2016;Bauer et al 2016).…”

Section: Discussionmentioning

confidence: 90%

“…These are recorded as the amplitudes of the harmonics derived from four elliptical Fourier coefficients which describe subtle aspects of shape (Lestrel 1974;1997;Kuhl and Giardina 1982;Haines and Crampton 2000;Iwata and Ukai 2002). Contour analysis of human posterior teeth has been previously conducted on Neandertals and modern humans (Benazzi et al 2011a, b;2012;Bailey et al 2014;2016;Bauer et al 2016). Similar analyses have been conducted using elliptical Fourier functions to identify the degree of sexual dimorphism of human first molars (Ferrario et al 1999) and to tooth crown shape of the mandibular permanent distal premolar (P 4 ) of Neandertals (Bailey and Lynch 2005).…”

Section: Data Acquisitionmentioning

confidence: 99%

Comparison of maxillary first molar occlusal outlines of Neandertals from the Meuse River Basin of Belgium using elliptical Fourier analysis

Williams

Lane

Anderson

2017

Anthropological Review

View full text Add to dashboard Cite

Several Neandertals derive from the karstic caves of the Meuse river tributaries of Belgium, including Engis 2, Scladina 4A-4 and Spy 1. These may form a group that is distinct in maxillary first molar occlusal outlines compared to La Quina 5 from Southwest France. Alternatively, chronological differences may separate individuals given that Scladina 4A-4 from MIS 5 is older than the others from MIS 3. Neolithic samples (n = 42) from Belgium (Maurenne Caverne de la Cave, Hastière Caverne M, Hastière Trou Garçon, Sclaigneaux and Bois Madame) dated to 4.6-3.9 kyr provide a context for the Neandertals. Dental casts were prepared from dental impressions of the original maxillary molars. Crown and occlusal areas as well as mesiodistal lengths were measured by calibrated Motic 3.0 microscope cameras. Occlusal outlines of the casts were captured through photostereomicroscopy and non-landmark smooth tracing methods. Occlusal outlines were processed using elliptical Fourier analysis within SHAPE v1.3 which reduced amplitudes of the harmonics into principal components (PC) axes. The first two PC axes group the Neandertals, although Scladina 4A-4 falls nearly outside the convex hull for the Neolithic sample. Neandertals are imperfectly separated from the Neolithic sample on PC3 and PC4, and completely distinct on PC5 and PC6. Scladina 4A-4 differs from the other Neandertals on most PC axes. Chronology may best explain the separation of Scladina 4A-4 from the more recent fossils, and particularly Spy 1 and La Quina 5 which are the most similar in maxillary first molar occlusal outline shape.

show abstract

“…Recent studies of molar shape have used landmark-based geometric morphometrics (GM) to investigate patterns of shape variation (Bailey et al 2014;Cooke 2011;Jones et al 2014;Singleton et al 2011). GM describes the shape changes of biological structures, while preserving the geometry of the specimens (Bookstein 1991;Gómez-Robles et al 2007, 2008; Rohlf and Marcus 1993;Slice 2005;White 2009).…”

Section: Introductionmentioning

confidence: 99%

Taxonomic Implications of Molar Morphology Variability in Capuchins

et al. 2015

View full text Add to dashboard Cite

Tooth morphology has been widely used to infer taxonomic affinities. Both morphological and genetic analyses have revealed significant differences among capuchins, suggesting that two distinct monophyletic groups exist: the gracile capuchins (Cebus) and the robust capuchins (Sapajus). We developed a geometric morphometrics (GM) model to determine if the two groups also show distinct molar shapes and to explore the influence of size, phylogeny, and biogeography in shaping molar morphology. We characterized first and second molar crown shape variability in seven species representative of the two genera (Cebus albifrons, C. olivaceus, Sapajus apella, S. robustus, S. libidinosus, S. nigritus, and S. xanthosternos), using two-dimensional (2D) and three-dimensional (3D) GM. The results showed that 2D GM discriminated the two groups better than 3D GM, possibly because it accounted for cusp position and crown contour, but not cusp height, which may be a useful trait for inferring adaptive foraging ecology but presents a risk of homoplasy. In addition, the presence of a phylogenetic signal in the first molar shape (2D) is likely to reflect similarity to the ancestral condition and provides evidence of gradual evolution of molar robustness in the robust clade. We suggest that the shape of the first molar is informative about phylogenetic affinities, whereas the shape of the second molar is more informative about biogeographic variability. However, molar shape similarities may be affected by convergent evolution, as environmental factors in different biogeographical regions may have a significant effect on molar morphology, as seen in the closely related capuchins. Int J Primatol

show abstract

Taxonomic differences in deciduous upper second molar crown outlines of Homo sapiens, Homo neanderthalensis and Homo erectus

Cited by 32 publications

References 27 publications

Allometry, merism, and tooth shape of the lower second deciduous molar and first permanent molar

Allometry, merism, and tooth shape of the lower second deciduous molar and first permanent molar

Comparison of maxillary first molar occlusal outlines of Neandertals from the Meuse River Basin of Belgium using elliptical Fourier analysis

Taxonomic Implications of Molar Morphology Variability in Capuchins

Contact Info

Product

Resources

About