Fig. 2

The measured signed difference values between the left and right angles (bars) follow the normal distribution (black curve) suggesting a lack of antisymmetry. A theoretical antisymmetry distribution would follow a bimodal distribution (orange line). The mean (the peak of the black curve) signed difference did not deviate from zero, indicating any directional asymmetry. However, a significant population had a considerable deviation from zero indicating fluctuating asymmetry