Neanderthal Physique: Rethinking Strength and Adaptation Through Ribcage Morphology
Reimagining the Neanderthal Thorax
Neanderthals have long fascinated researchers for their unique adaptations to Ice Age climates and challenging environments. A new study in the Journal of Human Evolution1 presents a virtual reconstruction of the Shanidar 3 ribcage, revealing distinct physiological traits that shaped their lives. The results not only affirm the "bell-shaped" thorax characteristic of Neanderthals but also challenge assumptions about their cold-adapted body plan.
A Closer Look at Neanderthal Ribcages
The study compared Shanidar 3’s ribcage with another Neanderthal specimen, Kebara 2, and 58 modern human ribcages. Both Neanderthal specimens exhibited wider, deeper lower thoraxes than modern humans, resembling the chest shape of humans adapted to cold climates. These ribcages were larger, stockier, and less tapered, indicative of high lung capacity and efficient diaphragmatic breathing.
“Neanderthals likely had a larger respiratory system than Homo sapiens, supporting their high metabolic rates and active lifestyles,” explained Dr. José López-Rey, the study's lead author.
Strength Over Endurance: Hunting Strategies and Physiology
Neanderthals relied on ambush hunting rather than long-distance pursuits typical of early modern humans. Their larger diaphragms and bell-shaped thoraxes enabled rapid oxygen intake, fueling bursts of intense activity. This physiology suggests they excelled in explosive strength, crucial for hunting large Ice Age prey such as woolly rhinoceroses and mammoths.
“The Neanderthal respiratory system supported higher activity rates, aligning with short, high-energy hunting strategies,” noted the researchers.
This differs from the endurance-focused adaptations of Homo sapiens, whose barrel-shaped ribcages are optimized for long-distance running and persistence hunting.
Challenging the Cold-Adapted Paradigm
Interestingly, Shanidar 3 and Kebara 2 lived in the relatively mild climate of the Levant rather than the frigid expanses of Ice Age Europe. Despite this, their ribcage morphology matched those of cold-adapted modern humans, prompting researchers to rethink the link between Neanderthal body structure and climate adaptation.
“Our findings suggest that the Neanderthal ribcage may not have been exclusively adapted to cold environments but was versatile enough for diverse habitats,” explained López-Rey.
This discovery opens questions about whether Neanderthal anatomy was shaped more by genetics, diet, or evolutionary convergence with cold-adapted humans.
Revisiting Respiratory and Metabolic Adaptations
Neanderthals likely had higher basal metabolic rates than modern humans, a necessity given their robust physiques. Their ribcages, combined with a flared pelvis, maximized lung capacity, enabling rapid oxygen exchange. This allowed them to generate the energy required for their demanding physical activities.
The virtual model of Shanidar 3, accessible through digital repositories, highlights the advanced techniques now used to study fragile fossil remains, offering unprecedented insights into hominin biology.
Future Research Directions
The Shanidar 3 study raises intriguing questions about Neanderthal adaptability and evolution. Researchers aim to further explore how Neanderthal anatomy influenced their survival across diverse environments. Upcoming projects may focus on broader comparisons with tropical and temperate populations of modern humans to unravel the genetic and ecological drivers of thoracic evolution.
Here are additional studies related to the unique morphology of Neanderthal ribcages and their respiratory adaptations:
3D Virtual Reconstruction of the Kebara 2 Neanderthal Thorax
Gómez-Olivencia, A., Barash, A., García-Martínez, D., Arlegi, M., Kramer, P., Bastir, M., & Been, E. (2018).
This study utilized 3D scans of the Kebara 2 Neanderthal skeleton, reconstructing its thorax to reveal enhanced lung capacity and a large diaphragm, adaptations suited to cold climates and high-energy activities.
Nature Communications, 9(1), 1-11. DOI: 10.1038/s41467-018-06803-zThe Functional Thoracic Morphology of the Shanidar 3 Neanderthal
López-Rey, J. M., García-Martínez, D., & Bastir, M. (2025).
This recent study provides further evidence of the "bell-shaped" ribcage of Shanidar 3, emphasizing its suitability for explosive strength and survival in harsh climates.
Journal of Human Evolution, 199(103629). DOI: 10.1016/j.jhevol.2024.103629.Adaptations of the Neanderthal Chest and Spine
Been, E., Gómez-Olivencia, A., & Kramer, P. A. (2020).
This paper investigates thoracic and spinal morphology, revealing adaptations for heat conservation and physical power, critical to the Neanderthals' lifestyle and environment.
Journal of Anatomy, 237(6), 1032-1048. DOI: 10.1111/joa.13209.Neanderthal Biomechanics and Energy Expenditure in Cold Climates
Churchill, S. E., & Rhodes, J. A. (2009).
This study explores the energetics of Neanderthal locomotion, linking their robust physiques and respiratory adaptations to survival in glacial climates.
Proceedings of the Royal Society B, 276(1656), 1131-1138. DOI: 10.1098/rspb.2008.1528.
These studies collectively enhance our understanding of Neanderthal adaptations, shedding light on their physiology, hunting strategies, and resilience in Ice Age conditions.
López-Rey, J. M., García-Martínez, D., & Bastir, M. (2025). Shanidar 3 ‘rings the bell’: Virtual ribcage reconstruction and its implications for understanding the Neanderthal bauplan. Journal of Human Evolution, 199(103629), 103629. https://doi.org/10.1016/j.jhevol.2024.103629