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Complete Neanderthal skeletons are almost unique findings. A very well-preserved specimen of this kind was discovered in 1993 in the deepest recesses of a karstic system near the town of Altamura in Southern Italy. We present here a detailed description of the cranium, after we virtually extracted it from the surrounding stalagmites and stalactites. The morphology of the Altamura cranium fits within the Neanderthal variability, though it retains features occurring in more archaic European samples. Some of these features were never observed in Homo neanderthalensis, i.e. in fossil specimens dated between 300 and 40 ka. Considering the U-Th age we previously obtained (>130 ka), the morphology of Altamura suggests that the archaic traits it retains may have been originated by geographic isolation of the early Neanderthal populations from Southern Italy. 3D reconstruction of a human cranium held within a deep cave in Italy is achieved with advanced virtual anthropology techniques; its features indicate that geographic isolation contributed to variation and evolution along the Neanderthal lineage. [ABSTRACT FROM AUTHOR]

Many fossil specimens exhibit deformations caused by taphonomic processes. Due to these deformations, even important specimens have to be excluded from morphometric analyses, impoverishing an already poor paleontological record. Techniques to retrodeform and virtually restore damaged (i.e. deformed) specimens are available, but these methods genenerally imply the use of a sparse set of bilateral landmarks, ignoring the fact that the distribution and amount of control points directly affects the result of the retrodeformation. We propose a method developed in the R environment and available in the R-package “Morpho” that, in addition to the landmark configurations, also allows using a set of semi-landmarks homogeneously distributed along curves and on surfaces. We evaluated the outcome of the retrodeformation, regarding the number of semi-landmarks used and its robustness against asymmetric noise, based on simulations using a virtually deformed gorilla cranium. Finally, we applied the method to a well-known Neanderthal cranium that exhibits signs of taphonomically induced asymmetry. [ABSTRACT FROM AUTHOR]

A number of different approaches are currently available to digitally restore the symmetry of a specimen deformed by taphonomic processes. These tools include mirroring and retrodeformation to approximate the original shape of an object by symmetrisation. Retrodeformation has the potential to return a rather faithful representation of the original shape, but its power is limited by the availability of bilateral landmarks. A recent protocol proposed by Schlager and colleagues (2018) overcomes this issue by using bilateral landmarks and curves as well as semilandmarks. Here we applied this protocol to the Middle Pleistocene human cranium from Steinheim (Germany), the holotype of an abandoned species named Homo steinheimensis. The peculiar morphology of this fossil, associated with the taphonomic deformation of the entire cranium and the lack of a large portion of the right side of the face, has given rise to different hypotheses over its phylogenetic position. The reconstruction presented here sheds new light on the taphonomic origin of some features observed on this crucial specimen and results in a morphology consistent with its attribution to the Neanderthal lineage. [ABSTRACT FROM AUTHOR]

Summary One of the features that distinguishes modern humans from our extinct relatives and ancestors is a globular shape of the braincase [ 1–4 ]. As the endocranium closely mirrors the outer shape of the brain, these differences might reflect altered neural architecture [ 4, 5 ]. However, in the absence of fossil brain tissue, the underlying neuroanatomical changes as well as their genetic bases remain elusive. To better understand the biological foundations of modern human endocranial shape, we turn to our closest extinct relatives: the Neandertals. Interbreeding between modern humans and Neandertals has resulted in introgressed fragments of Neandertal DNA in the genomes of present-day non-Africans [ 6, 7 ]. Based on shape analyses of fossil skull endocasts, we derive a measure of endocranial globularity from structural MRI scans of thousands of modern humans and study the effects of introgressed fragments of Neandertal DNA on this phenotype. We find that Neandertal alleles on chromosomes 1 and 18 are associated with reduced endocranial globularity. These alleles influence expression of two nearby genes, UBR4 and PHLPP1 , which are involved in neurogenesis and myelination, respectively. Our findings show how integration of fossil skull data with archaic genomics and neuroimaging can suggest developmental mechanisms that may contribute to the unique modern human endocranial shape. Highlights • We use fossil skull data to derive an index of endocranial shape in human MRI scans • In 4,468 Europeans, we screen introgressed Neandertal SNPs for association with the index • Lead SNPs consistently associate with reduced globularity in five separate subsamples • These SNPs affect neural expression of two genes linked to neurogenesis and myelination Gunz, Tilot et al. combine paleoanthropology, archaic genomics, neuroimaging, and gene expression to study biological foundations of the characteristic modern human endocranial shape. They find introgressed Neandertal alleles that associate with reduced endocranial globularity and affect expression of genes linked to neurogenesis and myelination. [ABSTRACT FROM AUTHOR]