TABLE 5.

Analysis of correlated character evolution during the diversification of temperature range by Synechococcus^a

Characterb	Group II	Group III	Group IV	Clone SH-94-5	Clone C9	Correlation coefficientsc
						Maximum parsimony			Neighbor joining			Maximum likelihood
						Tmax	Ratemax	Range	Tmax	Ratemax	Range	Tmax	Ratemax	Range
Topt	57	57	65	40	45	0.80	−0.52	−0.73	0.81	−0.56	−0.75	0.79	−0.53	−0.73
Tmax	61	63	70	55	55		−0.87	−0.96*		−0.89*	−0.97*		−0.88	−0.97*
Ratemax	1.65	1.60	0.72	1.20	1.43			0.96*			0.96*			0.96*
Range	21	18	15	25	25

^aPhenotypic data for the five sequence groups were transformed into four independent contrasts as described by Felsenstein (9). Branch length data from the three phylogenies in Fig. 1 were used in separate transformations, and correlations were determined for contrast pairs. 

^bOptimal temperature (T_opt), maximum temperature (T_max), and temperature range (Range) are expressed in degrees Centigrade. The units for maximum growth rate (Rate_max) are number of doublings per day. Character values were estimated from Table 4 as described in the text. 

^cAn asterisk indicates that the correlation coefficient is significantly different from zero at the α = 0.05 level as determined by a t test with df = 2.