Table 1.

PGLS models estimate the relationships between morphological links (input, output, and coupler) and kinematic transmission (KT) in the four-bar linkage system. For each regression, the maximum-likelihood (ML) estimate of phylogenetic signal (λ), the model coefficient (±1 s.e.), and the phylogenetic residual standard error (RSE) are presented.

predictor	ML estimate of λ	coeff. ± 1 s.e.	RSE	p-values
input	0.856	0.202 ± 0.316	0.009	0.527
output	0.912	−0.765 ± 0.079	0.005	2.24 × 10−11
coupler	0.878	0.025 ± 0.389	0.009	0.948