Vestigial organs are parts of the body that have lost their original function through evolution. These organs may have been useful to our ancestors, but are now no longer needed due to changes in our environment or lifestyle. Another example of vestigial organ in humans is: 



Coccyx: The coccyx, or tailbone, is a small bony structure at the base of the spine or backbone. It is a vestigial remnant of a tail that our primate ancestors once had. It no longer serves any functional purpose in humans.



Tailbone(Coccyx)
Tailbone(Coccyx)



•It is a small bony structure located at the bottom of the vertebral column, composed of three to five fused vertebrae (bones of backbone).

• It was present in our ancestors because they used this tail for grabbing tree branch light weight items, also referred to as prehensile tail, it could also be used to balance body.

• In humans, the coccyx no longer serves any functional purpose. It has become a vestigial structure as we have evolved to walk upright on two legs, losing the need for a tail. 




• The coccyx can sometimes cause pain or discomfort, particularly when sitting for long periods or during childbirth, but it is generally considered to be a non-functional vestigial structure. 

• Despite its apparent lack of function, the coccyx is still considered important for attachment of several muscles and ligaments that support the pelvic floor and help stabilize the sacrum and hips.

• Studies suggest that the gene for tail is still present in our body although it does not show it effect since it is in inactive stage.

• Very rare cases of infants born with tail have been witnessed across the different part of the earth. This phenomenon of reappearance of ancestral characters suddenly in present generation is known as Atavism.

• In rare cases, the coccyx may also be removed surgically, usually as a last resort for severe pain or injury.