25 Days of Skeletal Facts: Day 10 – The Ribs

Anatomy of a typical rib. Source: Teach Me Anatomy

Happy first night of Hanukkah! Humans have 12 pairs of ribs, for each of the 12 thoracic vertebrae we discussed a few days ago. As you can see in the image to the left, a typical rib actually articulates with two thoracic vertebrae, except for ribs 1, 10, 11, and 12. As we discussed yesterday, the first seven ribs articulate anteriorly with the sternum directly, these are the true ribs. Ribs 8-10 are known as “false ribs” since they articulate indirectly with the sternum, they share a costal cartilage connection with the 7th rib. Ribs 11 and 12 are your floating ribs, they have no connection with the sternum (see image below).

Rib cage skeletal anatomy. Source: Encyclopaedia Brittanica

Homo sapiens have been using faunal ribs to fashion specialized bone tools for thousands of years, first appearing in the archaeological record in Africa and then in Europe (d’Errico et al. 2012). In Europe, modern humans and Neanderthals overlapped for a period of time until Neanderthals were essentially driven to extinction by our species. A tool called a lissoir, used in leather working has been discovered in the record in a Neanderthal context from a site in southwestern France dated to about 50-47 thousand years ago (Soressi et al. 2013).

Figure 2 from Soressi et al. 2013: Lissoir specialized bone tools

This find indicates that Neanderthals were fashioning such specialized bone tools to use on animal hides likely before contact with modern humans, meaning that contact and information transmission from Homo sapiens to Neanderthals occurred earlier than previously thought or that Neanderthals invented this bone tool independently (Soressi et al. 2013). More recent research indicates a preference for source material, as Neanderthals were more likely to use the ribs of cattle, over those of deer, for their stability (Heritage Daily 2020).

That’s a wrap on the ribs and Neanderthal leather working tools – tomorrow we will work our way up to the shoulder girdle, starting with the clavicle.

REFERENCES & MORE TO EXPLORE

The Ribs. Teach Me Anatomy Series. 2020

Rib cage. Encyclopaedia Brittanica Anatomy and Physiology

Ancient Neanderthals were picky when choosing animals bones in making tools. Heritage Daily Paleoanthropology. May 2020

Neandertals made the first specialized bone tools in Europe. Soressi et al. PNAS. 2013

Identifying regional variability in Middle Stone Age bone technology:
The case of Sibudu Cave
. d’Errico et al. Journal of Archaeological Science. 2012

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