Table 2. Spearman rank correlation and partials correlation coefficients between the number of codons (FD_n) and the levels of neutral polymorphism (θ_neu) or the normalized neutral polymorphism (P_neu = θ_neu/d_neu), and between the number of conserved noncoding sites (FD_x) and the levels of neutral polymorphism (θ_neu) or normalized neutral polymorphism (P_neu = θ_neu/d_neu).

FDn vs θneu	FDn vs Pneu	FDx vs θneu	FDx vs Pneu	RR, GC, RD	Dn, Dx	FDn (FDx§)	dneu
−0.321 **	−0.236 **	−0.309 **	−0.216 **	○	○	○	○
−0.126 **	−0.060 **	−0.130 **	−0.059 **	•	○	○	○
−0.096 **	—†	−0.099 **	—†	•	○	○	•
−0.036*	−0.025* †	−0.042*	−0.021† *	•	○	•§	•(○)†
(6.67e-8)	(1.94e-4)	(2.34e-10)	(1.35e-3)
0.010NS	0.027† *	−0.025*	0.007† NS	•	•	•§	•(○)†
(1.51e-1)	(4.80e-5)	(1.42e-4)	(3.16e-1)

§: Correlation coefficients for FD_n versus θ_neu or P_neu was calculated here controlling for FD_x and the correlation coefficients for FD_x versus θ_neu or P_neu was calculated here controlling for FD_n.

†: Correlation coefficients for FD_n or FD_x versus P_neu were not calculated or were calculated without controlling for d_neu, as P_neu ( = θ_neu /d_neu) is not independent from d_neu.

**: P<1e-10.

*: 1e-10≤P<1e-3.

^NS P> = 1e-3.

Closed circles (•) indicate the controlled variables. Highly significant values (P<1e-10) are in bold. P-values are given in parentheses for marginally significant (1e-10≤P<1e-3) and nonsignificant (NS, P> = 1e-3) values.