Alice Walczer Baldinazzo
Comparison between a Neanderthal child (left) and A wise man is wise (on the right)
Analysis of infant fossils found in Germany suggests that Neanderthals had, even before birth, a pattern of bone growth close to that of modern humans, but also signs of possible episodes of metabolic stress in the early stages of life.
A recent study on rare children’s bones and teeth of Neanderthals discovered in Sesselfelsgrotte in southeastern Germany is shedding new light on the earliest stages of the development of this extinct species.
The results of the study indicate that Neanderthal fetal bone growth was, to a large extent, similar to humans modern, although some bones reveal signs of locally more accelerated development.
The research was carried out as part of the SHARP project, funded by National Geographic and led by Alvise Barbieri at ICarEHB, University of Algarve.
The team used non-invasive microcomputed tomography (micro-CT) to analyze bones and deciduous teeth of three juvenile individualsdated between approximately 75,000 and 50,000 years ago.
The study focused on a perinatal individual (Sesselfelsgrotte 1), represented by skeletal fragments, and two additional juveniles known from deciduous molars (Sesselfelsgrotte 2 and 3).
“The bone microstructure of Sesselfelsgrotte 1 indicates a stage of development corresponding to the end of the third trimester of pregnancy, confirming previous estimates”, explains Justyna J. Miszkiewiczfrom the University of Queensland and lead author of the study, at the university.
The analyzed bones reveal typical characteristics of an immature skeleton rapidly growing, including high vascularization and absence of secondary osteons.
However, some long bones, such as the femur and humeruspresent areas with greater compactness and structural organizationsuggesting possible faster local development.
Still, the researchers stress that, overall, the growth trajectory appears largely comparable to that of modern humans at this early stage of life.
Micro-CT images revealed mineralization defects in two molars, associated with interruptions in the tooth formation process, explains the study’s co-lead author, Ricardo Miguel Godinho
A rarity of fetal bones and teeth and infants of Neanderthals makes this study particularly relevant, contributing new data to understand the early development of this species.
By analyzing in detail the internal microstructure of fossilsthe study authors add important evidence to the debate about the developmental similarities and differences between Neanderthals and ourselves, A wise man.
The analyzes also revealed unusual changes in dentin of two deciduous molars.
“The micro-CT images also revealed mineralization defects unusual signs inside the dentin of the two deciduous molars of Sesselfelsgrotte 2 and 3, associated with interruptions in the tooth formation process”, he explained. Ricardo Miguel Godinhoco-main author of the study and researcher at ICArEHB, University of Algarve, in a statement sent to ZAP.
Justyna Miszkiewicz
Three-dimensional reconstruction of a tooth and arm bone from a Neanderthal child. A virtual microanatomical section of the tooth shows mineralization defects, while bone sections show the microanatomical organization
Although it is not possible to determine a specific cause, this type of change may be related to physiological disturbancessuch as vitamin D deficiency, calcium deficiency, or impaired calcium absorption.
As these structures are formed between the end of pregnancy and the first years of life, they can record very early physiological stress episodes.
According to the authors, these teeth may represent some of the oldest evidence of interglobular dentin in Neanderthalsabout 75,000 years old. The results suggest the occurrence of metabolic stress during the early stages of life, although the exact origin remains uncertain.
In addition to the implications for Neanderthal biologythe study, whose results were presented in a published last week in Royal Society Open Sciencedemonstrates the potential of virtual microanatomy to investigate fragile fossils without using destructive techniques.
Future investigations, with greater resolution and complementary approaches, should allow us to deepen our knowledge about the early development and health of these individuals.
