Template creation
The template consists of 900 landmarks: 101 fixed landmarks, 93 curves
(271 semilandmarks), and 18 surfaces (528 semilandmarks) (Supplementary
Figure 1). For the anatomical definitions of landmarks, please refer to
Supplementary Table 1. The number of curve or surface semilandmarks was
determined by the complexity of the curves or area covered. High density
landmark and semilandmark configurations, ranging from 800 to more than
1000 landmarks, have been demonstrated empirically to successfully
capture genuine biological signal (Cornette et al., 2013; Dumont et al.,
2016; Goswami et al., 2019; Gunz & Mitteroecker, 2013; Segall et al.,
2016; Watanabe et al., 2019; Weisbecker et al., 2019)
To ensure the repeatability of landmarking of the manually placed fixed
landmarks, three morphologically close specimens were digitised at ten
repetitions. Inter-repetition variation was much lower than
inter-individual variation, confirming the good repeatability of the
template used in this study (Supplementary Figure 2).