Early life of Neanderthals

Abstract

The early onset of weaning in modern humans has been linked to the high nutritional demand of brain development that is intimately connected with infant physiology and growth rate. In Neanderthals, ontogenetic patterns in early life are still debated, with some studies suggesting an accelerated development and others indicating only subtle differences vs. modern humans. Here we report the onset of weaning and rates of enamel growth using an unprecedented sample set of three late (∼70 to 50 ka) Neanderthals and one Upper Paleolithic modern human from northeastern Italy via spatially resolved chemical/isotopic analyses and histomorphometry of deciduous teeth. Our results reveal that the modern human nursing strategy, with onset of weaning at 5 to 6 mo, was present among these Neanderthals. This evidence, combined with dental development akin to modern humans, highlights their similar metabolic constraints during early life and excludes late weaning as a factor contributing to Neanderthals’ demise.

Teeth reveal juvenile diet, health and neurotoxicant exposure retrospectively: What biological rhythms and chemical records tell us

“…Developmentally-informed analyses of the tooth chemistry of captive and wild nonhuman primates, as well as human children with prospective nursing and health records, reveal the retrospective nutritional and physiological experiences of individuals in unprecedented detail. Despite a suggestion [61] that Ba/Ca patterns in teeth relate to dietary stress rather than dietary transitions, we have demonstrated Ba/Ca increases with the advent of milk intake and decreases with the cessation of nursing in multiple species, and this is not substantially altered F I G U R E 5 Rhesus macaque (Macaca mulatta) M1 showing correspondence between elemental concentration changes and the individual's nursing and medical histories. During an initial 25-day hospitalization beginning at 257 days of age, the infant was given a blood acidity regulator (K-Phos), a blood serum transfusion due to low serum protein, and several antibiotic courses, which coincide with marked decreases in Pb/Ca and Sr/Ca, as well as a drop in Ba/Ca.…”

“…Related attempts to document nursing in human deciduous teeth include studies of Sr/Ca [60,61] and calcium isotope ratios ( 44/42 Ca). [62] To test this first approach, we compared Sr/Ca and Ba/Ca ratios in teeth from the same subjects.…”

Strontium isotope evidence for Neanderthal and modern human mobility at the upper and middle palaeolithic site of Fumane Cave (Italy)

“…The laser ablation measured continuous values of these sections, and also included strontium isotope measurements of small sections of the inner part of two of the Fumane teeth that we also measured here. The values reported in Nava et al [ 57 ] for Fumane 1 (0.7093) and Fumane 2 (0.7088) are similar (within 1σ) of our strontium laser ablation measurements for the same teeth ( Table 2 ). Nava et al [ 57 ], based on comparisons with strontium measurements of archaeological vole teeth from Fumane, argue that the modern human (Fumane 2) was in a location distant from the site when their enamel was being formed.…”

“…The values reported in Nava et al [ 57 ] for Fumane 1 (0.7093) and Fumane 2 (0.7088) are similar (within 1σ) of our strontium laser ablation measurements for the same teeth ( Table 2 ). Nava et al [ 57 ], based on comparisons with strontium measurements of archaeological vole teeth from Fumane, argue that the modern human (Fumane 2) was in a location distant from the site when their enamel was being formed. This conclusion was made without knowledge of the bioavailable strontium values for the site and surrounding regions.…”

“…A recent study of the trace element composition of three Neanderthal teeth and one Upper Palaeolithic tooth from sites in north-eastern Italy has shown detailed information on weaning patterns for these individual teeth [ 57 ]. This study focused on using laser ablation on sections of the teeth at the enamel-dentine junction.…”