Table 1.

Summary statistics of mammalian clades. (Age is the age of the first split in the clade, S its number of extant species, m its average body size, %p the percentage zero-length branches, %m the percentage of extant species for which body size was observed and %g the percentage of interspecific body size variance explained by $s_{\text{a}}^2$.)

age	S	m	%p	%m	%g	λ	μ	$s_{\text{a}}^2$ ($s_{\text{c}}^2$=0)	$s_{\text{a}}^2$	$s_{\text{c}}^2$
63.6	258	0.42	26	55	31	0.075 (0.065–0.089)	0.008 (0.000–0.027)	0.046 (0.021–0.089)	0.035 (0.009–0.078)	0.095 (0.004–0.318)
90.2	67	0.56	39	54	90	0.049 (0.035–0.073)	0.016 (0.000–0.049)	0.157 (0.039–0.380)	0.140 (0.002–0.568)	3.904 (0.118–15.78)
54.5	152	0.02	34	64	593	0.106 (0.088–0.129)	0.013 (0.000–0.042)	0.159 (0.023–0.479)	0.144 (0.011–0.487)	1.069 (0.035–3.934)
62.3	275	6.38	22	64	23	0.106 (0.091–0.124)	0.013 (0.000–0.039)	0.028 (0.015–0.061)	0.017 (0.005–0.033)	0.038 (0.001–0.120)
48.5	307	111.44	39	61	25	0.107 (0.086–0.134)	0.037 (0.004–0.075)	0.044 (0.022–0.085)	0.020 (0.002–0.053)	0.103 (0.007–0.368)
73.5	254	1.82	30	53	34	0.130 (0.102–0.164)	0.066 (0.021–0.114)	0.023 (0.010–0.038)	0.016 (0.004–0.032)	0.033 (0.001–0.103)
56.4	272	0.24	28	51	144	0.129 (0.111–0.153)	0.017 (0.000–0.049)	0.093 (0.026–0.187)	0.067 (0.019–0.157)	0.147 (0.009–0.469)