A study of morphological variations of the human ear for its applications in personal identification

Abstract

Background: External human ear is considered to be a highly variable structure showing different morphological and individualistic features in different individuals and population groups. The uniqueness of the ear may be useful in establishing the identity of individuals by direct examination, during the examination of CCTV footage or analysis of the ear prints. Considering the forensic significance of the human ear and ear prints encountered at the scene of the crime, the present study is an attempt to evaluate various morphological characteristics of the ear in a north Indian population. Methodology: The sample for the present study comprises of 90 males and 87 females aged between 18 and 30 years. All the study participants were from upper reaches of Himachal Pradesh in North India. The morphological characteristics such as overall shape of the ear, size and shape of the tragus, earlobe, shape of the helix, and forms of Darwin’s tubercle were studied in the participants. Results: The oval-shaped ear was present among 40% of the males and 44.8% of the females in the study sample. The other types of the ear such as oblique, rectangular, round, and triangular were also found in both sexes. Bilateral asymmetry was observed in the shape of the ear. The shape of the tragus also varied with respect to the left and right sides as well as sexes. The earlobe showed different characteristics in different individuals. In nearly half of the cases in both males and females, the earlobe was found to be attached to the face; in many cases, it was free and in some partially attached. The size and shape of the earlobe also showed variations with respect to sides as well as sexes. The Darwin’s tubercle showed a variety of structures in both the left and right sides in both sexes. Conclusion: The present study shows that the individualistic characteristics of the ear can provide very useful information for personal identification in forensic examinations. The shape of the ear and the important structures such as the tragus, helix, earlobe, and Darwin’s tubercle show a variety of structures and individuality. The importance and variability of the human ear may encourage the researchers in conducting further studies and solving the forensic cases pertaining to the investigation of CCTV footage and in examination of dead in airplane crashes, intentional mutilation and dismemberment, explosions, or other mass disasters.