Background

F1000Research

2046-1402

F1000 Research Limited

London, UK

10.12688/f1000research.160629.2

Research Article

Articles

Morphology And Morphometry of Human External Ear with Its Significance in Sex Determination and Stature Estimation - An Observational Study

[version 2; peer review: 1 approved, 2 approved with reservations, 1 not approved]

Acharya

Shwetha

Data Curation Formal Analysis Project Administration Writing – Original Draft Preparation 1 Gupta

Chandni

Conceptualization Methodology Resources Software Supervision Validation Visualization Writing – Review & Editing https://orcid.org/0000-0002-9232-0946 a 1 Palimar

Vikram

Supervision Validation Visualization Writing – Review & Editing https://orcid.org/0000-0001-5258-1992 2 Guruprasad Kalthur

Sneha

Conceptualization Methodology Resources Software Writing – Review & Editing 1 Adhikari

Purnima

Data Curation Formal Analysis Project Administration Writing – Original Draft Preparation 1 1Department of Anatomy, Katsurba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India 2Department of Forensic Medicine , Katsurba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India

a chandni.palimar@manipal.edu

No competing interests were disclosed.

17 3 2025

2025

119

10 3 2025

2025

This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Background

The human ear is unique to individuals, and ear prints, like fingerprints, are discrete enough to distinguish identical twins. Therefore, the external ear could be used to identify both living and deceased individuals. Therefore, this study aimed to evaluate the stature and sexual dimorphism of the external ear using various morphometric parameters and morphological features for forensic identification.

Methods

This study included 40 participants (20 males and 20 females). Participants were between the age of 18-25yrs. Measurements were taken with the subject’s head in the Frankfort horizontal plane. 18 measurements were taken like ear length and width, lobule height and width, concha length and width, tragus length, morphological ear length, helical mastoid distal length, thickness of ear lobe, auricular inclination angle, antihelical take off angle, concha mastoid angle, auricular index, lobular index, concha index, ear attachment length index and conchal bowl depth on external ear were taken and the morphological features like shape of ear, ear lobe, darwin’s tubercle and ear tragus, attachment of ear lobe and form of helix of both the right and left ears were noted. A digital Vernier caliper was used to measure all parameters. The angles were measured using a goniometer. Normal distribution was verified using the Shapiro–Wilk test. For normally distributed parameters, an independent t-test was used, and for non-normally distributed parameters, the Mann-Whitney U test was used to compare sexes. To compare the right and left parameters, independent t-tests (for normally distributed data) and Mann-Whitney U tests (for non-normally distributed data) were applied. Sex determination and stature estimation were performed using logistic regression analysis.

Results

In males and females, the most common shape was oval, and the ear lobe was free. The most common shape of the ear lobe in males was arched, while in females, it was triangular. In males and females, the most common form of the helix was the concave marginal. In males, the most common shape of the tragus was round, whereas in females, it was long. In males and females, the most common shape of Darwin’s tubercle was enlarged. It was seen that the right lobe width showed perfect separation, indicating its potential as an extremely reliable predictor. It was noted that in females, the strongest correlation with height was with the ear inclination angle on both sides.

Conclusion

The results of this study can help forensic anthropologists identify the sex and stature of a person from various ear measurements.

Morphology Morphometry Sex External Ear Regression Equation Stature

The author(s) declared that no grants were involved in supporting this work.

Revised Amendments from Version 1

1. 3-4 new references are added and compared to the present study in discussion. 2. Added few more results findings in the conclusion to make it more informative. 3. Title has been changed as sample size was small, the word ‘population’ has been removed.

Introduction

Personal identification implies a determination of individualism established on specified morphological criteria that are distinctive to that person. In the circumstance of skeletal remnants, identification is very complex and needs precise investigation of these remnants. ¹ Human beings present a wide range of variations which are distinctive and facilitate differentiating a person from another. ²

In addition to DNA profiling, several morphological traits and biometric parameters have been used in forensic analyses to differentiate one individual from another. Certain structural attributes used for this purpose include fingerprints, facial traits, footprints and external ear. ^{3–
5}

As earprints, like fingerprints, are distinct enough, even the human ear can be used to recognize identical twins as it is unique to individuals. ^{6–
8}

External ear is the most definitive features of the human face, also referred as the pinna or auricle. ² Many forensic anthropologists revealed that auricle plays a vital role in identification of gender, stature, age and ethnicity. ⁹ Additionally, the shape, location and measurement of the auricle are specific to everyone same as the fingerprint thus assisting its utilization in forensics. ² Frequently, during a crime scene investigation ear inscriptions are typically found on gates and windows where a possible criminal has been hearing for likely assault. Therefore, such spots are gathered and assessed using saved records to determine a match with the accused. Therefore, earprints provide valuable forensic evidence. ¹⁰ When an accused person wears protective hand gloves, his fingerprints will not be available during those cases, and ear morphology and biometrics are frequently used. ¹¹

Ear morphology and morphometry are more important than typical biometric attributes such as facial recognition because they are rarely affected by aging. However, it was not affected by the facial expression alterations. In addition, there is no effect of anxiety on the ear as it can happen in other traits such as retina and the iris. ^{12,
13} Hence, the ear is used widely as a forensic tool for individual identification purposes because of its permanency and distinctiveness in persons after birth to maturity. ¹⁴

It has been found that sex can be identified by ear measurements with up to 69.3% precision in male individuals and 72% in females. ⁹ Previous studies have shown that estimation of stature and sexual dimorphism can be done using morphologic parameters of the ear like ear length, width, ear lobular length and width. ^{15,
16}

To date, no study has been conducted on human ear morphometry and morphology in the South Indian Population. Therefore, this study was conducted to estimate stature, assess sexual dimorphism, and racial specificity based on the morphometry and morphology of the external ear in the South Indian population and to derive a regression equation to predict sex and stature estimation for forensic identification.

Methods Study type: Observational study

Institutional ethical approval was obtained from the Kasturba Medical College and Kasturba Hospital Institutional Ethics Committee on 31 ^st May 31, 2024, before starting the research. (IEC NO – IEC2 – 113/2024)

Written informed consent was obtained from the participants before collecting their data and for publication of their images as per the informed consent form template obtained from the Kasturba Medical College and Kasturba Hospital Institutional Ethics Committee.’.

We used the STROBE Reporting Guidelines for our study; a complete checklist is available under the Reporting Guidelines. ¹⁷

Study Period: The current research was carried out from June 2024 to October 2024.

Study location: Department of Anatomy.

Sample Size: 40. (sample size computation using effect size, d=0.5; significance level=0.05; power=0.8; sample size, n=40; i.e., 20 males and 20 females)

Study population: 18-25yrs.

Inclusion criteria: •

All participants who do not having ear any deformity

•

Only young individuals of 18-25 yrs were included

Exclusion criteria: •

Subjects having ear deformity

•

Subjects below 18 and above 25 were eliminated from the research

Detailed description of procedure/processes:

Measurements were taken with the subject’s head in the Frankfort horizontal plane.

The following measurements were taken: ( Figures 1 and 2).

Figure 1. Linear measurements done on ear. Figure 2. Angular measurements done on ear.

1) Ear length: It was determined as the distance between the most dependent part of the lobule to the superior end of the auricle.

2) Ear Width: It was determined as the distance between root of ear to helix where concavity is maximum.

3) Lobule height: It was measured as the distance from intertragic notch to most dependent part of the lobule.

4) Lobule width: It was determined as the maximal distance across the lobule taken transversely.

5) Concha length: It was determined as the distance from intertragic notch to the posterior aspect of tragus.

6) Concha width: It was determined as the distance from point where helix concavity is maximum to the posterior aspect of tragus.

7) Tragus length: Length between intertragic notch to tragion.

7) Morphological ear length: It was determined as the straight distance between otobasion superior and otobasion inferior.

8. Helical mastoid distal length: the distance from the mastoid process to the helix rim at the most posterior level of the superior auricular rim.

9. Thickness of ear lobe.

10. Auricular inclination angle: The angle measured between the length of the ear and the vertical.

11. Antihelical take off angle: The angle measured as the antihelix projects from the concha bowl.

12. Concha mastoid angle: The angle measured between the mastoid process and the concha bowl.

13. Auricular index = ear width ÷ ear length×100.

14. Lobular index = lobular width ÷ lobular length×100.

15. Concha index = concha width ÷ concha length×100.

16. Ear attachment length index = morphological ear length ÷ ear length×100.

18. Conchal bowl depth.

Tools used: A digital Vernier caliper with a precision of 0.001 mm was used to measure all parameters. The angles were measured using a goniometer. To avoid intra- and inter-observer bias, each measurement was performed twice by two people, and its average was recorded afterwards.

In addition to these morphometric measurements various morphological parameters were also noted down: 1.

Ear Shape: Round, oval, triangular and rectangular.

Attachment of ear lobe: free, partially attached and fully attached.

Shape of ear lobe: arch, square, tongue and triangular.

Form of helix: rolled, wide, flat and concave marginal.

Shape of ear tragus: knob, round and long.

Shape of Darwin’s tubercle: projected, enlarged and nodosity.

Statistical analysis

The data were evaluated using Jamovi 2.4 computer software. ¹⁸ Normal distribution was verified using the Shapiro–Wilk test. For normally distributed parameters, an independent t-test was used, and for non-normally distributed parameters, the Mann-Whitney U test was used to compare sexes. To compare the right and left parameters, independent t-tests (for normally distributed data) and Mann-Whitney U tests (for non-normally distributed data) were applied. Sex determination and stature estimation were performed using logistic regression analysis.

Underlying data is included in the Underlying Data section. ¹⁹

Results Morphological parameters

Ear shape

In males, the most common shape was oval in 10 (50%), followed by triangular in 5 (25%), round in 3 (15%), and rectangular in 2 (10%). In females, the most common shape was oval 9 (45%), followed by triangular 5 (25%), round 4 (20%) and rectangular 2 (10%) ( Figure 3).

Figure 3. A. Shapes of ear. B. Attachments of ear lobe. C. Shapes of ear tragus.

Attachment of ear lobe

In males, the most common ear lobe was free in 10 cases (50%), followed by partially attached in 7 (35%), and fully attached in 3 (15%) cases. In females, the most common ear lobe was free in 8 cases (40%), followed by partially attached and fully attached in 6 (30% each) cases ( Figure 3).

Shape of ear lobe

In males, the most common shape was arched 10 (50%), followed by triangular 6 (30%), square 3 (15%), and tongue-shaped 1 (5%). In females, the most common shape was triangular (n = 7, 35%), followed by arched (n = 6, 30%), square (n = 5; 25%), and tongue-shaped (n = 2; 10%) ( Figure 4).

Figure 4. A. Shapes of ear lobe. B. Forms of helix. C. Shapes of Darwin’s tubercle.

Form of helix

In males most common form of helix was concave marginal 9 (45%), followed by wide 5 (25%), flat and rolled 3 (15% each). In females most common form of helix was concave marginal 7 (35%), followed by flat 5 (25%), wide and rolled 4 (20% each) ( Figure 4).

Shape of ear tragus

In males, the most common tragus was round 12 (60%), followed by 5 (25%), and 3 (15%). In females, the most common shape of the tragus was long 9 (45%), followed by round 7 (35%), and knob shaped 4 (20%) ( Figure 3).

Shape of Darwin’s tubercle

In males, the most common shape of Darwin’s tubercle was enlarged by 10 (50%), followed by projected 8 (40%) and nodosity 2 (10%). In females, the most common shape of Darwin’s tubercle was enlarged in nine (45%), followed by projected seven (35%), and nodosity in four (20%) cases ( Figure 4).

Morphometric parameters

The descriptive statistics of all the parameters of the right and left sides were compared using the Mann-Whitney test (non-normally distributed data) and independent T Test (normally distributed data), as shown in Table 1.

Table 1. Descriptive statistics of right and left side with their comparison using Mann whitney test (non-normally distributed data) and independent T Test (normally distributed data).

Parameters		Mean ± SD	P value
Ear length (mm)	Right	63.2 ± 7.86	0.381
Ear length (mm)	Left	62.3 ± 7.77	0.381
Ear width (mm)	Right	30.0 ± 2.85	0.411
Ear width (mm)	Left	29.4 ± 3.05	0.411
Lobe height (mm)	Right	25.2 ± 2.20	0.038 *
Lobe height (mm)	Left	24.2 ± 2.37	0.038 *
Lobe width (mm)	Right	21.8 ± 4.21	0.758
Lobe width (mm)	Left	21.6 ± 4.08	0.758
Concha length (mm)	Right	14.5 ± 2.30	0.881
Concha length (mm)	Left	14.5 ± 2.12	0.881
Concha width (mm)	Right	14.0 ± 1.78	0.860
Concha width (mm)	Left	14.0 ± 1.82	0.860
Morphological ear length (mm)	Right	32.4 ± 2.78	0.299
Morphological ear length (mm)	Left	31.8 ± 2.17	0.299
Concha bowl depth (mm)	Right	11.3 ± 1.98	0.602
Concha bowl depth (mm)	Left	11.0 ± 1.88	0.602
Helical mastoid distal length (mm)	Right	16.3 ± 1.44	0.099
Helical mastoid distal length (mm)	Left	15.7 ± 1.38	0.099
Tragus length (mm)	Right	15.4 ± 2.40	0.405
Tragus length (mm)	Left	15.1 ± 2.37	0.405
Thickness of ear lobe (mm)	Right	7.14 ± 1.07	0.362
Thickness of ear lobe (mm)	Left	6.94 ± 0.91	0.362
Auricular index	Right	48.0 ± 6.07	0.617
Auricular index	Left	47.5 ± 5.71	0.617
Lobular index	Right	87.3 ± 18.1	0.545
Lobular index	Left	89.7 ± 17.4	0.545
Concha index	Right	97.4 ± 9.50	0.989
Concha index	Left	97.4 ± 11.4	0.989
Ear attachment length index	Right	185 ± 8.40	0.996
Ear attachment length index	Left	168 ± 7.33	0.996
Ear inclination angle (°)	Right	15.1 ± 0.77	0.002 *
Ear inclination angle (°)	Left	14.6 ± 0.81	0.002 *
Antihelical take off angle (°)	Right	24.8 ± 1.43	0.045 *
Antihelical take off angle (°)	Left	24.2 ± 1.36	0.045 *
Concha mastoid angle (°)	Right	88.7 ± 1.63	0.011 *
Concha mastoid angle (°)	Left	87.9 ± 1.65	0.011 *

P value < 0.05-Significant.

Comparing the parameters on the right and left sides, it was noticed that lobe height (p-value-0.038), ear inclination angle (p-value-0.002), antihelical takeoff angle (p-value-0.045), and concha mastoid angle (p-value-0.011) showed significant differences (p-value <0.05). The other parameters were not statistically significant.

The descriptive statistics of all the parameters of females with their comparison of the right and left sides using the Mann-Whitney test (non-normally distributed data) and independent T Test (normally distributed data) are shown in Table 2.

Table 2. Descriptive statistics of female parameters with their right and left comparison using Mann whitney test (non-normally distributed data) and independent T Test (normally distributed data).

Parameters	Mean± SD
Parameters	Left	Right	P value
Ear length	68.4±2.26	69.5± 2.11	0.096
Ear width	30.9±2.67	31.2± 2.49	0.737
Lobe height	24.8± 2.39	25.2± 1.74	0.291
Lobe width	25.2±2.14	25.7± 1.99	0.515
Concha length	16.0± 1.79	16.3± 1.77	0.569
Concha width	14.5±2.04	15.1± 1.75	0.285
Morphological ear length	33.4±1.35	34.8± 1.36	0.002 *
Concha bowl depth	12.6±1.05	12.9±1.06	0.368
Helical mastoid distal length	15.2±1.48	15.8±1.72	0.236
Tragus length	15.5±1.57	16.0±1.78	0.357
Thickness of ear lobe	7.47±0.898	7.88± 0.878	0.152
Auricular index	45.2± 3.10	44.8± 3.00	0.718
Lobular index	103± 13.9	102±11.1	0.738
Concha index	90.7± 7.00	93.1±6.25	0.259
Ear attachment length	48.8 ±2.48	50.1± 2.86	0.326
Ear inclination angle	14.8± 0.927	15.4 ± 0.886	0.060
Anti helical take of angle	25.2± 0.834	25.8± 0.912	0.055
Concha mastoid angle	88.3± 1.45	88.8± 1.56	0.158
Ear length	68.4±2.26	69.5± 2.11	0.096
Ear width	30.9±2.67	31.2± 2.49	0.737
Lobe height	24.8± 2.39	25.2± 1.74	0.291
Lobe width	25.2±2.14	25.7± 1.99	0.515
Concha length	16.0± 1.79	16.3± 1.77	0.569
Concha width	14.5±2.04	15.1± 1.75	0.285
Morphological ear length	33.4±1.35	34.8± 1.36	0.002 *
Concha bowl depth	12.6±1.05	12.9±1.06	0.368
Helical mastoid distal length	15.2±1.48	15.8±1.72	0.236
Tragus length	15.5±1.57	16.0±1.78	0.357
Thickness of ear lobe	7.47±0.898	7.88± 0.878	0.152
Auricular index	45.2± 3.10	44.8± 3.00	0.718
Lobular index	103± 13.9	102±11.1	0.738
Concha index	90.7± 7.00	93.1±6.25	0.259
Ear attachment length	48.8 ±2.48	50.1± 2.86	0.326
Ear inclination angle	14.8± 0.927	15.4 ± 0.886	0.060
Anti helical take of angle	25.2± 0.834	25.8± 0.912	0.055
Concha mastoid angle	88.3± 1.45	88.8± 1.56	0.158

P value < 0.05-Significant.

When comparing the parameters of females on the right and left sides, it was noticed that only the morphological ear length (p = 0.002) showed significant differences (p <0.05). The other parameters were not statistically significant.

The descriptive statistics of all the parameters of males with their comparison of the right and left sides using the Mann-Whitney test (non-normally distributed data) and independent T Test (normally distributed data) are shown in Table 3.

Table 3. Descriptive statistics of male parameters with their right and left comparison using Mann whitney test (non-normally distributed data) and independent T Test (normally distributed data).

Parameters	Mean± SD Median (Min-Max)
Parameters	Left	Right	P value
Ear length	56.2±6.43	56.9 ± 6.13	0.758
Ear width	28.0 ±2.70	28.8± 2.72	0.348
Lobe height	23.7 ±2.28	25.2 ± 2.63	0.065
Lobe width	18.0±1.54	18.0± 1.19	0.933
Concha length	13.0±1.15	12.8 ± 1.17	0.787
Concha width	13.5±1.43	12.9± 0.938	0.190
Morphological ear length	30.3± 1.72	30.0± 1.49	0.617
Concha bowl depth	9.48± 1.04	9.62± 1.14	0.626
Helical mastoid distal length	16.3±1.01	16.8± 0.875	0.083
Tragus length	14.7± 2.96	14.8± 2.83	0.850
Thickness of ear lobe	6.41±0.575	6.41± 0.656	0.992
Auricular index	49.7±6.82	51.1± 6.77	0.253
Lobular index	76.6±8.17	72.1±8.17	0.093
Concha index	104± 11.1	102± 10.3	0.482
Ear attachment length	54.5± 6.82	53.4 ±6.53	0.626
Ear inclination angle	14.3± 0.615	14.9± 0.572	0.004 *
Anti helical take of angle	23.2± 1.01	23.9± 1.25	0.077
Concha mastoid angle	87.6± 1.82	88.6± 1.73	0.033 *

P value < 0.05-Significant.

When comparing the parameters of males on the right and left sides, it was noticed that only the ear inclination angle (p = 0.004) and concha mastoid angle (p = 0.033) showed significant differences (p <0.05). The other parameters were not statistically significant.

A comparison of parameters between males and females is shown in Table 4. When comparing parameters between males and females, it can be noticed that lobe height right (p-value-0.970) and left (p-value-0.162), concha width left (p-value-0.071), tragus length right (p-value-0.135) and left (p-value-0.316), ear attachment length right (p-value-0.318) and left (p-value-0.335), ear inclination angle right (p-value-0.053) and left (p-value-0.059), concha mastoid angle right (p-value-0.753), and left (p-value-0.218) were not significantly different, and the rest of the parameters were significantly different (p-value <0.05).

Table 4. Comparison of male and female parameters using independent T-Test.

Parameters	P value
Ear length right	<.001 *
Ear length left	<.001 *
Ear width right	0.005 *
Ear width left	.001 *
Lobe height right	0.970
Lobe height left	0.162
Lobe width right	<.001 *
Lobe width left	<.001 *
Concha length right	<.001 *
Concha length left	<.001 *
Concha width right	<.001 *
Concha width left	0.071
Morphological ear length right	<.001 *
Morphological ear length left	<.001 *
Concha bowl depth right	<.001 *
Concha bowl depth left	<.001 *
Helical mastoid distal length right	0.028 *
Helical mastoid distal length left	0.006 *
Tragus length right	0.135
Tragus length left	0.316
Thickness of ear lobe right	<.001 *
Thickness of ear lobe left	<.001 *
Auricular index right	<.001 *
Auricular index left	0.010 *
Lobular index right	<.001 *
Lobular index left	<.001 *
Concha index right	0.003 *
Concha index left	<.001 *
Ear attachment length right	0.318
Ear attachment length left	0.335
Ear inclination angle right	0.053
Ear inclination angle left	0.059
Anti helical take of angle right	<.001 *
Anti helical take of angle left	<.001 *
Concha mastoid angle right	0.753
Concha mastoid angle left	0.218

P value < 0.05-Significant.

Gender and ear dimension

Binomial logistic regression analyses were conducted to examine the correlations between various ear measurements and sex.

Multiple ear measurements were significant predictors of sex, as shown in Table 5. 1.

Right ear length: (sex) = -59.889 + 0.916 × (right ear length)

Left ear length: (sex) = -45.564 + 0.710 × (left ear length)

Right lobe width: This predictor showed perfect separation, indicating extremely high predictive power

Right concha bowl depth: (gender) = -40.82 + 3.67 * (right concha bowl depth)

Left concha bowl depth: (gender) = -47.90 + 4.38 * (left concha bowl depth)

Table 5. Showing logistic regression analysis of ear morphometric predictors for gender.

Predictor	p value	Odds Ratio (95% CI)	Accuracy	AUC
Right ear length	<.001	2.50 (1.12-5.57)	0.925	0.988
Left ear length	<.001	2.03 (1.28-3.22)	0.925	0.978
Right lobe width	<.001	7.11e+11 (0.00 – Inf )	1.000	1.000
Right concha bowl depth	<.001	39.1 (1.49-1023)	0.975	0.985
Left concha bowl depth	<.001	80.2 (1.86-3464)	0.950	0.990

CI = confidence interval; AUC = area under the curve.

These results suggest that various ear measurements, particularly ear length, lobe width, and concha bowl depth, are strong predictors of sex. Right lobe width showed perfect separation, indicating its potential as an extremely reliable predictor.

Stature and gender specific ear dimension

Female

Looking through the correlation matrices, the strongest correlation with height is with the ear inclination angle of both sides, with •

Right ear inclination angle: Pearson’s r = 0.489, (p-value-0.029)

•

Left ear inclination angle: Pearson’s r = 0.599 (p-value-0.005)

Linear regression analyses were conducted to examine the correlation between the height and ear inclination angle.

There was a substantial positive correlation between height and the right and left ear inclination angles. The regression equations were as follows: Right Ear Inclination Angle ( in degrees ) = 7.72 + 1.40 × ( Height in feet ) Left Ear Inclination Angle ( in degrees ) = 5.02 + 1.80 × ( Height in feet )

The consistent finding of a significant positive correlation between height and ear inclination angle provides strong evidence of a solid association between these variables. The findings indicate that for every one-foot increase in height, the ear inclination angle increases by approximately 1.40 to 1.80 °.

Male

In males, there was no statistically significant correlation between height and any of the ear measurements. This suggests that in males ear dimensions may not be reliable for predicting a person’s height.

Discussion

The pinna shape and dimensions are influenced by age, sex, and racial origin. ² Some of the features of the external ear are unique and peculiar in that they resemble the fingerprint of a person. ²⁰ Since the inclination, shape, and dimensions of the human external ear are very specific, they have been recognized as valuable anthropological variables for studying racial differences. ²¹

Rai et al. found that approximately 38.8% of male and 36.9% of females had attached earlobes. The most common shape of the external ear was oval in both male and females. The ear index was higher in the male ears, whereas the lobule index was higher in the female ears. In their study, there were substantial differences between males and females in the following parameters: ear length right and left, ear width right and left, concha width, length of right ear lobule, and lobule index. ²² In our study also most common ear shape was oval in both males and females. Fifteen% of male and 30% of females had attached ear lobes. The ear index in our study was higher in females while the lobule index was higher in males. This difference might be due to ethnic origin, as they conducted the study in North India and we conducted the study in South India. In our study, there were substantial differences between males and females in the following parameters: ear length right and left, ear width right and left, concha width, and lobule index, except right lobule length.

Kumari et al. found that in males the ear length, width, and lobule width of both ears were higher as compared to females. They also found by linear regression coefficient analysis that there was a strong association between right and left ear length and stature in females was. ²³ In our study, all these parameters were greater in females than in males. A strong association between the right and left ear inclination angles and stature was observed in females using linear regression coefficient analysis. These differences in findings could be ethnic, as they have conducted research in North India, and we have conducted research in South India.

Hiware et al. found that statistically significant differences were observed between males and females in right ear height, left ear width, and width of the right and left ear lobe. ²⁴ In our study, we also found statistically significant differences between these parameters in males and females.

Laxmi et al. found that the shape of the ear was oval in most specimens. The ear height and width were greater in males than females. The left auricular and lobular indices were higher in females than in males. Females had a longer right lobe than males. Tragus length was found to be greater in males than in females. ²⁵ In our study, ear height and width were greater in females than in males. The left auricular index was higher in females than in males, but the lobular index was higher in males than in females. Right lobe length was the same in both sexes. Tragus length was found to be greater in females than in males. These differences in findings might be ethnic, as they have conducted research in the northwestern region of India, and we have conducted the study in South India.

Verma et al. found that free and attached ear lobes were noted in 35% and 65% of the cases, respectively. The oval ear shape was the most common, followed by triangular, rectangular, and round shapes. No statistical differences were noted in the ear and lobular indices between males and females. ²⁶ In our study, 45% of free and 55% of attached ear lobes were observed. The oval ear shape was the most evident, followed by triangular, round, and rectangular. In our study, statistical differences were observed in the ear and lobular indices between males and females. These differences in findings can be ethnic, as they have conducted research in the northwestern and northeastern regions of India, and we have conducted the study in South India.

Farhan et al. found significant differences were noticed regarding gender in lobule height with respect to sex. Free lobules were noted in 66% of males compared to 54% of females. The most common ear shape was triangular in males and rectangular in females. ²⁷ In our study, there was no significant difference noted regarding gender in lobule height between the sexes. In our study, 50% of male free lobules were noted compared to 40% of female free lobules. The most common shape was oval in both males and females. These differences in findings can be racial, as they have conducted research in Iraq, and we have conducted research in South India.

Bozkır et al. observed that all parameters were higher in males than in females. While in our study most parameters were higher in females as compared to males. ²⁸ These differences in findings can be racial as they have conducted the research in Turkey, and we have conducted the research in South India.

Rani D et al. found that ear length, ear breadth, exhibited significant sex differences on both sides (p<0.05). Significant bilateral differences (p<0.05) were reported for all the measurements of the ear in males except for lobule height, whereas significant side differences (p<0.05) were shown for lobule width among females. ²⁹ In our study also significant sex differences was noted on both sides in ear length (p<0.001 in each) and ear breadth (Right- p-0.005, left- p-.001). But there was no significant side differences noted in any of the parameters of the ear among males and females.

Khobkhun P et al. found that there was no significant difference in any of the auricular dimensions between the right and the left sides. They also found that the auricular length, auricular width, and conchal length were larger in male than in female participants. ³⁰ While in our study we also found that that there was no significant difference in any of the auricular dimensions between the right and the left sides except lobe height (p-0.038). In our study all parameters related to auricle were larger in males as compared to females.

Boesoirie SF et al. found that auricle length, width, as well as concha length of men tended to be greater than women. However, the women’s lobule length was longer compared to men’s, while the lobule and concha width tended to be the same. ³¹ In our study in our study all parameters related to auricle were larger in males as compared to females. This might be due to racial differences as they have conducted the study in Sudanese population and the present study was conducted in Indian population.

Fakorede et al. found that oval ears were more common, followed by round ears. Arch-shaped lobules were the most frequently seen. Free earlobe attachment was the most common among the Nigerian populations, followed by partial attachment, while the attached earlobe was the least expressed. They also found that a knob-shaped tragus was the most prevalent. The wide form of the helix was the most evident. The nodosity-shaped Darwin tubercle appears to be the most prevalent. When comparing the right and left ear parameters, it was noted that all parameters were statistically significant, except for ear width. They also found that ear length, lobule height, lobule width, and concha length mainly contribute to sex classification. ¹¹ In our study, the most common ear shape was oval and arch-shaped. Even earlobe attachment was free in our study, followed by partial and full attachment. In our study, round-shaped tragus and concave marginal form of the helix were mostly observed. An enlarged Darwin’s tubercle was mostly observed. Comparing the parameters on the right and left sides, it was noticed that lobe height (p-value- 0.038), ear inclination angle (p-value- 0.002), antihelical takeoff angle (p-value- 0.045), and concha mastoid angle (p-value- 0.011) showed significant differences (p-value <0.05). The other parameters were not statistically significant. In our study, ear length, lobe width, and concha bowl depth were strong predictors of gender. Some differences in findings can be racial, as they have conducted research in Nigeria, and we have conducted research in South India.

Morphological changes and morphometric parameters of the human ear can be utilized jointly with forensic DNA evaluation to solve complicated incidents, principally where fingerprints or facial recognition tools are not accessible. ¹¹ The results of this study will help in identification of stature and sex from various ear parameters.

Limitations of the study

•

Small sample size.

•

To predict male sex, no ear parameters were significant.

This study aimed to predict sex and stature based on ear dimensions. In both males and females, the common shape was oval, and the ear lobe was free. The most common shape of the ear lobe in males was arched, while in females, it was triangular. In males and females, the most common form of the helix was the concave marginal. In males, the most common shape of the tragus was round, whereas in females, it was long. In males and females, the most common shape of Darwin’s tubercle was enlarged.

Comparing the parameters on the right and left sides, it was noticed that lobe height, ear inclination angle, antihelical takeoff angle, and concha mastoid angle showed significant differences (p-value <0.05).

When comparing the parameters of females on the right and left sides, it was noticed that only the morphological ear length showed significant differences (p <0.05). When comparing the parameters of males on the right and left sides, it was noticed that only the ear inclination angle and concha mastoid angle showed significant differences (p <0.05).

When comparing parameters between males and females, it can be noticed that lobe height right and left, concha width left, tragus length right and left, ear attachment length right (and left, ear inclination angle right and left, concha mastoid angle right, and left were not significantly different (p-value >0.05).

It was seen that the right lobe width showed perfect separation, indicating its potential as an extremely reliable predictor. It was noted that in females, the strongest correlation with height was with the ear inclination angle on both sides.

Ethical considerations

Data availability

Morphology And Morphometry of Human External Ear with Its Significance in Sex Determination and Stature Estimation - An Observational Study. https://figshare.com/articles/dataset/Data_Excel_sheet/28120586?file=51439520. doi: 10.6084/m9.figshare.28120586. ¹⁹

The project contains the following underlying data: Data sheet of all 40 cases.

Extended data

The study contains the following extended data.

Morphology And Morphometry of Human External Ear with Its Significance in Sex Determination and Stature Estimation - An Observational Study. https://doi.org/10.6084/m9.figshare.28137164.v5. ³²

Data are available under the terms of the Creative Commons Zero “No rights reserved” data waiver (CC0 1.0 Public domain dedication).

Reporting guidelines

We used STROBE checklist for “Morphology And Morphometry of Human External Ear with Its Significance in Sex Determination and Stature Estimation - An Observational Study.” https://figshare.com/articles/online_resource/Strobe_checklist/28120598?file=51564029 doi: 10.6084/m9.figshare.28120598. ¹⁷

Data are available under the terms of the Creative Commons Zero “No rights reserved” data waiver (CC0 1.0 Public domain dedication).

Acknowledgements

Nil

References 1

Deopa

Thakkar

Prakash

: Anthropometric measurements of the external ear in medical students in the Uttarakhand region. J. Anat. Soc. India. 2013;62(1):79–83. 10.1016/S0003-2778(13)80018-4

Alexander

Stott

Sivakumar

: Morphometric study of human ear. J. Plast. Reconstr. Aesthet. Surg. 2011;64:41–47. 10.1016/j.bjps.2010.04.005

Gibelli

Mapelli

Obertovà

: Age changes of facial measurements in European young adult males: Implications for the identification of the living. Homo. 2012;63(6):451–458. 22990009

10.1016/j.jchb.2012.08.002

Kumar

Singla

: Ear biometric: sex, bilateral, and ethnic differences among Brahmin and Yadav communities of Bundelkhand region using PCA technique. Int. J. Sci. Eng. Res. 2013;4:799–805.

Krishan

Kanchan

: Identification: Prints-ear. Payne-James

Byard

, editors. Encyclopedia of forensic and legal medicine. 2nd edn. Oxford: Elsevier Ltd.;2015; pp.74–80. 10.1016/B978-0-12-800034-2.00210-X

Chang

Bowyer

Barnabas

: Comparison and combination of ear and face images in appearance-based biometrics. IEEE Trans. Pattern Anal. Mach. Intell. 2003;25:1160–1165. 10.1109/TPAMI.2003.1227990

Rahman

Islam

Bhuiyan

: Person identification using ear biometrics. Int. J. Comput. Internet Manag. 2007;15(2):1–8.

Daramola

Oluwaninyo. : Automatic ear-recognition system using back-propagation neural network. Int. J. Video Image Process Netw. Secur. 2011;11(1):28–32.

Murgod

Angadi

Hallikerimath

: Anthropometric study of the external ear and its applicability in sex identification: assessed in an Indian sample. Aust. J. Forensic Sci. 2013;45(4):431–444. 10.1080/00450618.2013.767374

Meijerman

: Inter- and intra-individual variation in earprints. Netherlands: Leiden University;2006. Doctoral Thesis. Accessed 9 Apr 2020. Reference Source

Fakorede

Adekoya

: Ear morphology and morphometry are potential forensic tools for the identification of the Hausa, Igbo, and Yoruba populations in Nigeria. Bull. Natl. Res. Cent. 2021;45:205. 10.1186/s42269-021-00665-0

Victor

Bowyer

Sarkar

: Evaluation of facial and ear biometrics. Proc. Int. Conf. Pattern Recog. 2002;1:429–432.

Amirthalingam

Radhamani

: Multimodal approach to face and ear biometric systems. Int. J. Comput. Sci. Issues. 2013;10(5):234–241.

Muntasa

Sirajudin

: Global and local structure fusion for face image recognition. Telkomnika. 2011;9(1):125–132. 10.12928/Telko mnika.v9i1.678

Natekar

De Souza

: Demarking and identifying points-reliable criteria for determining sex from the external ear. Indian J. Otolaryngol. 2012;18(1):24. 10.4103/0971-7749.98292

Laxman

: Determination of stature in the hybrid population using external ear morphometry. Medico Legal Update. 2019;19(1):164–168. 10.5958/0974-1283.2019.00033.1

Gupta

: Morphology And Morphometry of Human External Ear with Its Significance in Sex Determination and Stature Estimation - An Observational Study. Strobe checklist. figshare. [Online resources]. 2025. 10.6084/m9.figshare.28120598

Reference Source

Jamovi software 2.4. Reference Source

Gupta

: Morphology And Morphometry of Human External Ear with Its Significance in Sex Determination and Stature Estimation - An Observational Study. Data excel.[Dataset]. figshare. 2025. 10.6084/m9.figshare.28120586

Reference Source

Dhanda

Badhan

Garg

: Studies on the development of latent ear prints and their significance in personal identification. Prob. Forensic Sci. 2011;88:285–295.

Akpa

Ibiam

Ugwu

: Anthropometric study of the pinna among southeast Nigerians. J. Expt. Res. 2013;1:47–50.

Rai

Diwakar

Kumar

: Morphometrical variation in the structure of the external ear: A comparative study in males and females of North India. Afr.J.Bio.Sc. 2024;6(SI1):217–226.

Kumari

Devadas

Patel

: Morphometric Analysis of External Ear to Estimate the Stature and Sexual Dimorphism in North Indians: A Cross-sectional Study. J. Clin. Diagn. Res. 2022;16(5):MC10–MC14. 10.7860/JCDR/2022/50599.16398

Hiware

AlFaqeeh

Alattallah

: Morphometric Parameters of the Ear and Their Sexual Dimorphism in the Eastern Province of Saudi Arabia. Cureus. 2024;16(1):e51625. 38196990

10.7759/cureus.51625

Laxmi

Palak

Kullar

: External Ear: morphological and morphometric study in North Indian males and females. Int. J. Anat. Res. 2017;5(2.2):3866–3869. 10.16965/ijar.2017.206

Verma

Sandhu

Verma

: Morphological Variations and Biometrics of Ear: An Aid to Personal Identification. J. Clin. Diagn. Res. 2016;10(5):ZC138–ZC142. 27437349

10.7860/JCDR/2016/18265.7876

Farhan

Al-Jewari

Al-Maathidy

AQA

: Morphological assessment of Ear auricle in a group of Iraqi subjects and its possible role in personal identification. IJAE. 2019;124(3):432–442.

Bozkır

Karakas

Yavuz

: Morphometry of the External Ear in Our Adult Population. Aesth. Plast. Surg. 2006;30:81–85. 16418881

10.1007/s00266-005-6095-1

Rani

Krishan

Sahani

: Variability in human external ear anthropometry-Anthropological and forensic applications. Clin. Ter. 2021;172(6):531–541. 34821348

10.7417/CT.2021.2374

Khobkhun

Pungrasmi

Suwajo

: An anthropometric study of the external ear in the Thai population. JPRAS. 2022;75:1417–1423. 10.1016/j.bjps.2021.11.065

Boesoirie

Handayani

Gatera

: Determination of the Difference Between Men and Women Anthropometry Auricles Using Photogrammetric Method in Sundanese Ethnic Group. Clin. Cosmet. Investig. Dermatol. 2022;15:2133–2141. 36217409

10.2147/CCID.S380115

PMC9547621

Gupta

: Morphology And Morphometry of Human External Ear with Its Significance in Sex Determination and Stature Estimation - An Observational Study. PIS and IC forms.[Dataset]. figshare. 2025. 10.6084/m9.figshare.28137164

Reference Source

10.5256/f1000research.179146.r371387

Reviewer response for version 2

Sezgin

Nurdan

1 Referee 1Kütahya Health Sciences University, Kütahya, Turkey

Competing interests: No competing interests were disclosed.

29 4 2025

2025

This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

recommendation

approve-with-reservations

There are some points that need attention in the study:

1. The number of current publications in the references can be increased. Ear morphology studies have attracted more attention in recent years. Therefore, the number of publications after 2020 can be increased.

2. It may be more meaningful to express measurements with anthropometric points (landmarks) when defining them. In fact, this marking can be done in the images.

3. Working with 40 ear samples can be considered sufficient in terms of descriptive statistics. However, when comparing between sexes, the number is insufficient.

4. A table is given regarding the statistical significance of ear measurements, but it is not given which measurement has which value in female and male. Including this information is important in the following respect: if the sex difference in ear measurements seems large, a sample group of 40 people can be considered sufficient. However, if the difference is small or at an average level, the number of samples are small (I am evaluating it for 40 people).

5. Therefore increasing the sample size of the study and making a new statistical calculation will both take time and reduce the motivation of the researchers. So, the title of this study can be updated as follows: If the study will continue with a larger sample, "pilot study" should be added. If this study will remain with 40 people and a new, larger database will not be used, it is recommended to update it by adding "preliminary observational study".

Is the work clearly and accurately presented and does it cite the current literature?

Partly

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Partly

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

Forensic anthropology, identification, age and sex estimation from facial images and ear images

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.

Gupta

Chandni

Anatomy, Kasturba Medical college, Manipal, Manipal, Karnataka, India

Competing interests: No competing interests were disclosed.

5 5 2025

Response: Done added.

2. It may be more meaningful to express measurements with anthropometric points (landmarks) when defining them. In fact, this marking can be done in the images.

Response- Added the landmarks in the images.

3. Working with 40 ear samples can be considered sufficient in terms of descriptive statistics. However, when comparing between sexes, the number is insufficient.

Response- This sample size we got from our statistics department by seeing from previous studies as we were doing both morphometric and morphological study.

Response- Added the values of measurement in table 4. And Sex difference is seen in all parameters except lobe height (right: p-value = 0.970, left: p-value = 0.162), concha width (left: p-value = 0.071), tragus length (right: p-value = 0.135, left: p-value = 0.316), ear attachment length (right: p-value = 0.318, left: p-value = 0.335), ear inclination angle (right: p-value = 0.053, left: p-value = 0.059), and concha mastoid angle (right: p-value = 0.753, left: p-value = 0.218). All other parameters were found to be significantly different, with p-values less than 0.05.

Response: Added in title “Morphological And Morphometric analysis of Human External Ear with Its Implications in Sex and Stature Estimation -– A Preliminary Observational Study”

10.5256/f1000research.179146.r374367

Reviewer response for version 2

Emeka

Anyanwu Godson

1 Referee https://orcid.org/0000-0002-7367-807X 1Kampala International University, Ishaka, Uganda

Competing interests: No competing interests were disclosed.

29 4 2025

2025

recommendation

reject

The focus of this observational study was the morphology and morphometry of the human external ear studied in 40 young adults (20 males, 20 females) aged 18–25. Also studied was the reliability of generated data for sex determination and stature estimation in the scope of forensic purposes. The study used standardized measurements and morphological assessment of different ear features (lobe type, tragus shape, helix form, Darwin’s tubercle) and revealed significant sexual dimorphism and correlations to height, as well as the right ear lobe width and ear inclination angle as potential reliable predictors. The results indicate the forensic significance of external ear characteristics in personal identification.

Title as it is looks a bit clumsy, I suggest: Morphological and Morphometric Analysis of the Human External Ear: Implications for Sex and Stature Estimation

The two sentences in the background of the abstract are awkwardly phrased with some redundancy . The word “Therefore” is used twice in consecutive sentences, which is redundant , and this disrupts the flow. The awkward phrasing of the sentence … “. this study aimed to evaluate the stature and sexual dimorphism of the external ear” is slightly misinforming because the ear is not attributed with stature and sexual dimophism, rather the stature and gender of individuals can be estimated from its features.

i have problem with method part of the abstract, i feel the study design [eg cross sectional , longitudinal etc] and recruiting process [ eg simple random, purposive etc] would have been captured very briefly here. Suggestion “This was a cross-sectional observational study involving ……. recruited from ………… using purposive sampling/ simple random technique.

The statement where you used the word “like” as captured in this sentence “18 measurements were taken like ear length and width, lobule height and width …..’ does not clearly connote you measured these parameters, you are indirectly saying you measured parameters that are similar to …. Pls recast sentence

In this sentence “A digital Vernier caliper was used to measure all parameters. The angles were measured using a goniometer. “ you said that a digital caliper was used to measure all parameters, when this is not correct, because the angles are part of the parameters studied and you measured them with goniometers. Pls recast sentence

I have concerns with the current results paragraph because it lacks quantitative depth and clarity in highlighting statistical significance, distribution patterns, and key findings that strengthen forensic value.

Your conclusion is vague and lacks scope and specificity. In your revision summarize which specific measurements were most useful (e.g., right earlobe width, ear inclination angle), as identified in your results.

The two sentences below are from your introduction, while one is in the present tense, the other is in the past. Pls recast to maintain consistency

This statement is an over-statement pls recast: “To date, no study has been conducted on human ear morphometry and morphology in the South Indian Population’

Methods section lacks coherence and feels more like a list of procedures than a well-structured narrative. The section reads like disconnected bullet points rather than a continuous, organized description of the research process. Also the narrative jumps between ethical clearance, reporting guidelines, study period, and sampling criteria without transition or thematic grouping.

The same observation made in 11 above is also noted in the discussion sections of this work

Is the work clearly and accurately presented and does it cite the current literature?

If applicable, is the statistical analysis and its interpretation appropriate?

Partly

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Are the conclusions drawn adequately supported by the results?

Partly

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

My study encompasses spine biomechanics, obesity-associated musculoskeletal problems, and anatomical risk determinants in orthopedics and neurodegenerative diseases. I am recognized for promoting forensic morphometry and anatomical teaching through creative tools, including the award-winning Anatomy Adventure board game.

I confirm that I have read this submission and believe that I have an appropriate level of expertise to state that I do not consider it to be of an acceptable scientific standard, for reasons outlined above.

Gupta

Chandni

Anatomy, Kasturba Medical college, Manipal, Manipal, Karnataka, India

Competing interests: No competing interests were disclosed.

5 5 2025

Title as it is looks a bit clumsy, I suggest: Morphological and Morphometric Analysis of the Human External Ear: Implications for Sex and Stature Estimation- Changed the title

The two sentences below are from your introduction, while one is in the present tense, the other is in the past. Pls recast to maintain consistency- Changed

This statement is an over-statement pls recast: “To date, no study has been conducted on human ear morphometry and morphology in the South Indian Population’- Changed

The same observation made in 11 above is also noted in the discussion sections of this work- Corrected the discussion and I have discussed the previous results with our study and added why they are similar or different from our study and added few more studies.

10.5256/f1000research.179146.r374370

Reviewer response for version 2

Asghar

Adil

1 Referee 1All India Institute of Medical Sciences, Patna, India

Competing interests: No competing interests were disclosed.

25 4 2025

2025

recommendation

approve-with-reservations

Clarify Limitation Regarding Generalizability

Issue: Although “population” was removed from the title, the findings are still generalized in the text.

Required Action: Re-emphasize that results are applicable only to young South Indian adults (18–25 years) and may not generalize across age, region, or ethnicity.

Address Small Sample Size in Interpretation

Issue: With just 40 participants, some results—like "perfect separation" in logistic regression—might be artifacts of overfitting.

Required Action: Clearly state that results are preliminary and exploratory, and that larger studies are needed to validate these regression models and confirm predictors.

Include AUC Curves or Graphs for Sex Prediction

Issue: AUC values are reported, but no visual ROC curve or regression diagnostics are shown.

Required Action: Include graphical output of logistic regression model (e.g., ROC curve, classification plot) to visually support claims of predictive strength.

�� Minor Revisions Suggested

Language and Grammar

Rephrase awkward phrases:

“Subjects who do not having ear deformity” → “Subjects without any ear deformities.”

“Measurement was performed twice by two people” → “Each measurement was independently performed twice by two observers.”

Perform a light grammar and clarity check across the manuscript.

Duplicate or Misplaced Text

Table headers or descriptions appear to repeat on some pages (possibly due to PDF formatting).

Check for repetitive statistical table text and ensure clean formatting before indexing.

Improve Figure Captions and Labels

Figures 1–4 could use more descriptive captions to be interpretable on their own.

Include scale markers where appropriate.

Is the work clearly and accurately presented and does it cite the current literature?

Yes

If applicable, is the statistical analysis and its interpretation appropriate?

Partly

Are all the source data underlying the results available to ensure full reproducibility?

Partly

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Partly

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

Gupta

Chandni

Anatomy, Kasturba Medical college, Manipal, Manipal, Karnataka, India

Competing interests: No competing interests were disclosed.

26 4 2025

Clarify Limitation Regarding Generalizability

Issue: Although “population” was removed from the title, the findings are still generalized in the text.

Required Action: Re-emphasize that results are applicable only to young South Indian adults (18–25 years) and may not generalize across age, region, or ethnicity- Added in the abstract, discussion and conclusion

Address Small Sample Size in Interpretation

Issue: With just 40 participants, some results—like "perfect separation" in logistic regression—might be artifacts of overfitting.

Required Action: Clearly state that results are preliminary and exploratory, and that larger studies are needed to validate these regression models and confirm predictors.- Added in limitations

Include AUC Curves or Graphs for Sex Prediction

Issue: AUC values are reported, but no visual ROC curve or regression diagnostics are shown.

Required Action: Include graphical output of logistic regression model (e.g., ROC curve, classification plot) to visually support claims of predictive strength.- ROC curves are added as Figure 5

�� Minor Revisions Suggested

Language and Grammar

Rephrase awkward phrases:

“Subjects who do not having ear deformity” → “Subjects without any ear deformities.”- Changed

“Measurement was performed twice by two people” → “Each measurement was independently performed twice by two observers.”- Changed

Perform a light grammar and clarity check across the manuscript.- Done all grammatical mistakes are corrected throughout the manuscript.

Duplicate or Misplaced Text

Table headers or descriptions appear to repeat on some pages (possibly due to PDF formatting).- Removed

Check for repetitive statistical table text and ensure clean formatting before indexing.- Done

Improve Figure Captions and Labels

Figures 1–4 could use more descriptive captions to be interpretable on their own.- Added more description to all the figures legends.

Include scale markers where appropriate.- As measurements were not taken on images we can’t show the scale markers. In images we have shown from where-to-where measurements has been taken.

10.5256/f1000research.179146.r371386

Reviewer response for version 2

Agarwal

Jolly

1 Referee https://orcid.org/0000-0002-0379-1296 1ANATOMY, Government doon medical college, Dehradun, Uttarakhand, India

Competing interests: No competing interests were disclosed.

21 3 2025

2025

recommendation

approve

no comments

Is the work clearly and accurately presented and does it cite the current literature?

Partly

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Yes

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

Anatomist, Osteology, Medical Education, Histology and Radiology

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

10.5256/f1000research.176552.r363729

Reviewer response for version 1

Sezgin

Nurdan

1 Referee 1Kütahya Health Sciences University, Kütahya, Turkey

Competing interests: No competing interests were disclosed.

4 3 2025

2025

recommendation

approve-with-reservations

A current issue has been addressed. I suggest updates on a few issues:

- Not enough current publications have been included

- Conclusion is not satisfactory enough. I attribute this to the small number of subjects.

- If the term "population" is in the title, 40 people is an unacceptable number. In this case, I do not see it possible to rewrite the study with new participants. Therefore, the word "population" should be removed from the study title.

Is the work clearly and accurately presented and does it cite the current literature?

Partly

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Partly

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

Forensic anthropology, identification, age and sex estimation from facial images and ear images

Gupta

Chandni

Anatomy, Kasturba Medical college, Manipal, Manipal, Karnataka, India

Competing interests: No competing interests were disclosed.

8 3 2025

A current issue has been addressed. I suggest updates on a few issues:

- Not enough current publications have been included

Response:- Added 3 more new references and compared with the present study.

- Conclusion is not satisfactory enough. I attribute this to the small number of subjects

Response:- I have added few more points in conclusion to make it more informative.

Response:- I had removed the word population from the study title.

10.5256/f1000research.176552.r363735

Reviewer response for version 1

Agarwal

Jolly

1 Referee https://orcid.org/0000-0002-0379-1296 Agrawal

Anurag

2 Co-referee 1ANATOMY, Government doon medical college, Dehradun, Uttarakhand, India 2Pulmonary Medicine, Government Doon Medical College, Dehradun, Uttarakhand, India

Competing interests: No competing interests were disclosed.

13 2 2025

2025

recommendation

approve

Summary – The present observational study focuses on evolution of stature and sexual dimorphism of external ear using various morphometric parameters and morphological features for forensic identification. The external ear can be used to evaluate sex and stature of person from various ear measurements which is very useful for forensic anthropologist.

Major points – The total 40 individuals were taken for the study in which 20 were male and 20 were female. The age of individual was 18-25 years. Linear and angular measurements of external ear were taken, various morphological parameters of ear were also noted.

The most common shape in both male and female was oval. The free ear lobe was most common in both male and female. The most common shape of ear lobe in male was arched while in female triangular. In both male and female, the helix was concave marginal. The most common shape of ear tragus in male is round while in females it was long. Darwin’s tubercle was enlarged in both male and female.

The various morphometric parameters of right and left side like lobe height, ear inclination angle, anti-helical take off angle, concha mastoid angle was statistically significant.

The morphological ear length in females of right and left side showed statistically significant difference.

In males, the ear inclination angle, concha mastoid angle of right and left side showed statistically significant difference.

Gender wises most of the morphometric parameters of ear were statistically significant, therefore sexual dimorphism can be determined.

In females significant positive correlation between height and ear inclination angle were found therefore ear parameter can be used as predictor of stature of female.

Minor points – Height and any of ear measurements were not statistically significant in males.

The sample size of the study is less which is mentioned in limitation of study.

Is the work clearly and accurately presented and does it cite the current literature?

Partly

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Yes

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

Anatomist, Osteology, Medical Education, Histology and Radiology

We confirm that we have read this submission and believe that we have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.