TABLE 2

Directional positive or negative selection does not affect codon volatility

dN/dSMean starting
 volatility ±SEMaMean ending
 volatility ±SEMaIncreasebDecreasecRatiod
8.00.74647 ± 0.000850.74678 ± 0.00085777177401.004
4.00.74650 ± 0.000850.74690 ± 0.00085783776941.019
2.00.74610 ± 0.000850.74650 ± 0.00085778077691.001
1.00.74737 ± 0.000850.74676 ± 0.00085772277011.003
0.50.74768 ± 0.000850.74577 ± 0.00085770078680.979
0.20.74620 ± 0.000850.74702 ± 0.00085756075271.004
0.10.74734 ± 0.000850.74792 ± 0.00085687569070.995
  • a Under none of the conditions examined is the mean ending volatility significantly different from the mean starting volatility (P > 0.05, Z-test).

  • b Number of cases (in 20,000 simulations) in which the ending codon volatility exceeds the starting volatility.

  • c Number of cases (in 20,000 simulations) in which the starting codon volatility exceeds the ending volatility.

  • d Ratio of the number of increase cases to the number of decrease cases. Under none of the conditions examined is the ratio significantly different from 0 (P > 0.05, binomial test).