Table 2.

Results for (A) phylogenetic tests, (B) generalized linear mixed-effects models (GLMM) for phylogeny×photosynthetic type, and (C) GLMM for phylogeny×habitat water availability (A) Estimated λ values for 40 indices of the 33 grass species (N). (B) GLMM with phylogeny (S, subfamily) and photosynthetic type (PT, PCK, and non-PCK) as two fixed factors, species as a random effect. (C) GLMM with phylogeny (S, subfamily) and habitat water availability (MAP, mean annual precipitation) as two fixed factors, species as a random effect. Sample size (n), λ values, P values for phylogenetic tests; Total number of individuals sampled (n), F values, d.f. (for each factor), and P values for GLMM are reported. Level of significance: * P<0.05; ** P<0.01; *** P<0.001; ns, not significant. Significant results are in bold.

Ecophysiological trait	N	(A) Phylogenetic test			n	(B) GLMM of C4 subtype			(C) GLMM of habitat water
		λ	P (λ=0)	P (λ=1)		S (1, 29)	PT (1, 29)	S×PT (1, 29)	S (1, 29)	MAP (1, 29)	S×MAP (1, 29)
Morphology and leaf longevity
Culm height	33	0.03	ns	**	165	3.12*	.05	.99	2.46	.01	.38
Leaf length	33	0.00	ns	***	224	4.65*	3.25	1.22	1.35*	.02	.71
Leaf width	33	0.28	*	***	224	10.22**	.20	.32	7.63*	.28	.46
Leaf area	33	0.00	ns	***	223	1.39	.04	2.16	.85	.36	.12
Leaf volume	33	0.00	ns	***	223	1.06	.03	4.81*	.49	.43	.62
Leaf dry weight	33	0.00	ns	***	223	.31	.25	4.38*	.14	1.23	1.56
Seed size	33	0.25	*	***	165	56.24***	2.75	1.12	58.85***	7.73**	8.17**
Leaf longevity (days)	33	0.00	ns	**	163	.24	.61	.82	.34	1.37	.25
Leaf structure
LDMC	33	0.00	ns	***	222	.00	.44	.16	.02	.63	4.67*
SLA	33	0.00	ns	***	214	1.27	2.02	2.88	.22	.40	4.96*
Leaf density	33	0.00	ns	***	217	.02	1.00	.66	.00	1.53	5.14*
Leaf thickness	33	0.00	ns	***	222	.92	.06	3.96	.31	.09	.30
Stomatal traits
Guard cell length	33	0.71	***	**	99	18.89***	1.63	.23	16.63***	1.09	1.64
Stomatal width	33	0.62	*	**	99	9.71**	3.37	1.13	7.29**	.31	.19
Stomatal pore length	33	0.58	**	***	99	15.14***	.69	.22	14.18***	.91	2.20
Abaxial SD	33	0.93	***	ns	92	13.17**	4.70*	3.89	14.01***	.26	3.10
Adaxial SD	33	0.00	ns	***	99	8.76*	1.27	2.07	3.00	.00	2.65
Abaxial SPI	33	0.08	ns	***	92	6.08*	1.30	8.33**	3.07*	.20	.23
Adaxial SPI	33	0.01	ns	***	99	1.07	.41	1.18	.68	.05	.23
g max	33	0.00	ns	ns	99	1.37	4.22*	.01	3.27	.02	7.38
Leaf curling
Leaf curling rate
Relative width loss	33	0.52	**	***	163	14.97***	.01	.15	13.12**	1.94	4.17
Absolute width loss	33	0.00	ns	***	163	.02	1.53	.00	.21	.12	1.32
Leaf weight loss rate
Relative weight loss	33	0.00	ns	**	163	.00	.32	2.48	.15	.00	.27
Leaf cuticular conductance	33	0.00	ns	*	163	1.42	.02	.04	.61	.28	.73
Relative width/weight ratio loss	33	0.36	ns	***	163	5.79*	.40	.01	3.21	1.58	1.53
Leaf hydraulic traits
Ψ sat	33	0.03	ns	***	162	3.46*	.01	.03	3.28	2.88	7.21*
Ψ osat	33	0.00	ns	**	162	1.10	1.03	4.81*	2.31	.62	3.48
TLP	33	0.00	ns	*	162	1.01	1.28	5.06*	2.48	.56	2.91
ε	33	0.00	ns	**	162	1.11	1.55	2.66*	2.74	.95	7.82**
Ψ	33	0.01	ns	**	196	3.08*	1.32	.76	2.29	.06	.62
K leaf	33	0.00	ns	***	165	1.37	.03	2.12*	.64	.33	1.36
Leaf gas exchange
A	33	0.00	ns	***	140	.13	.27	3.26	.31	.10	.29
g s	33	0.00	ns	***	140	.11	.15	1.48	.05	.02	.01
C i	33	0.00	ns	***	137	.34	.00	.09	.02	.01	.46
E	33	0.00	ns	***	140	.05	.06	2.94	.41	.20	.09
WUEi	33	0.00	ns	***	140	1.29	.01	.02	.23	.03	.33
Habitat traits
Water range	33	0.00	ns	***	33	.27	.00	.00	1.06	1.68	1.54
Water score	33	0.55	*	ns	33	17.28**	.82	.21	20.53***	20.66***	11.43**
MAT	28	0.90	*	ns	28	1.92	2.96	.08	.07	23.89***	10.13**
MAP	28	0.22	ns	***	28	6.71*	.47	.60	–	–	–