The query is: how many ribs are in the human body? The answer is quite simple. The number of pairs of ribs in a human body are 12. So, we can say that there are about 12 pairs of ribs in total which protect us from injury and also provide support to internal organs. It also serves as the channel that drains the blood from the heart and lungs back into the aorta. The ribs or cambia are aligned under the sternum. If we remove this bone, then we can open up the thoracic cavity and look inside our chests, we will find the ribs along with the collar bones.
We have the costal, subcostal, medial, lateral and a series of transversal ribs. There are two types of ribs that can be observed in the body. These are the cuboidal ribs which are bony and the neural ribs which are cartilaginous. In humans there are 12 pairs of ribs in human body with 12 pairs of equal length. Each rib has a length that is determined by the height, width, length to width ratio, and other bone attributes.
So the longer the length, the longer the ribcage. The ribs meet the body when you are standing up and the overlap is quite small. So there is little space between the ribs. The minimum space between the ribs is a good 3cm. There are two other bones present in the thoracic cavity, these are the sternum and the clavicle.
Characteristics of Ribs in a Human Body
When we talk about the pairs of ribs, there are certain characteristics which can be observed by the shape, size, position, and shape. The width is determined by the width of the rib cage and the length is determined by the height of the rib cage.
The Rib Structure
The rib structure in the human body is very complicated as we have about 12 pairs of ribs in human body with 12 pairs of equal and unequal length. In the body, the rib bones are stacked in pairs of unequal length, and along with this there is a series of transversal ribs. The rib structures of humans and animals are quite similar.
In humans, the ribs have two bones or two bones in pairs, they are similar to each other. However, we can observe a bit difference in the ribs, as in birds, they have four bones in pairs. The length of the ribs in humans is 7.8 inches. This is about 24 cm. The maximum measurement of the rib cage is 75cm.
History of Ribs
In Human Civilization, it is believed that the first homo sapiens existed in Africa. The homo sapiens species underwent a period of evolution and the next generation had more bones in their bodies, the homo erectus had four ribs in each. Then the homo erectus changed into the homo heidelbergensis and during that time, the homo erectus family also changed their family structure. In the homo heidelbergensis family, the term ‘crib’ was used and the cadaver (human body) was found in an advanced stage, it had no ribs.
Therefore the homo erectus family used the term ‘roof’. This family is also known as the australopithecines and the most probable ancestors to the human species. It is said that after the discovery of the homo erectus family and the association of the skeleton with the four ribs, the homo heidelbergensis family and also a group called the homo avus, they had two to three ribs in each set. The homo avus family was the one of the more primitive homo sapiens species that followed the less aggressive/cunning approach of the homo erectus family.
The homo heidelbergensis family also had the limitation of only four ribs in each set. The earliest remains of the homo sapiens were found in Kenya. However, the oldest human skeleton with ribs and sternum was discovered at Jebel Irhoud and was dated to 32000 BCE. The ancestors of modern humans, the homo sapiens came from Africa and also from Asia. There are a few extinct hominids that lived in Eurasia that are known as Homo erectus, Homo habilis, and Homo rudolfensis. But these extinct hominids had only two ribs in each set.
The homo heidelbergensis family also had the limitation of only four ribs in each set. The earliest remains of the homo sapiens were found in Kenya. However, the oldest human skeleton with ribs and sternum was discovered at Jebel Irhoud and was dated to 32000 BCE. The ancestors of modern humans, the homo sapiens came from Africa and also from Asia.
There are a few extinct hominids that lived in Eurasia that are known as Homo erectus, Homo habilis, and Homo rudolfensis. But these extinct hominids had only two ribs in each set. Many species of animals are known to have their own version of ribs. Some of the closest relatives to humans, the platypus has four in each set. There are 12 pairs of ribs in human body in present.
Functions of Ribs
Some of the functions of the ribs in the body are as follows:
- Gastrocnemius Muscle
The use of the four ribs is similar to the use of the clavicles, sternum and sternum for all the functions. The reason for this is that the musculature is important to produce movement, and the only muscles that it is easy to use are the ribs.
The movement of the rib cage is one of the four specific examples that we can use to measure movement of the body. The rib cage is the only way that we can measure the movement of the rib cage. The ribs form a critical motion of the body and they enable movement. The human body is associated with movement, and as the ribs increase in size, they support the heavy body and provide support to the weight.