Table 1.

Comparisons of evolutionary rates of (a) length measures and (b) mass measures in ungulates. The model (a) compares length measures (i.e., horn/antler length, muzzle width and sperm head, midpiece and flagellum length), while model (b) compares mass measures (testes and body mass). Note that the two models assess different numbers of ungulate species. The observed (σ²_obs) and common evolutionary rate (σ²_common) are shown for each trait. Additionally, presented are the AIC values for the observed (AIC_obs) and common (AIC_common) model, log-likelihood values for the observed (Log(L_obs)) and common models (Log(L_common)), and the log-likelihood ratio tests (LRT) and associated p-values for comparisons between observed and constrained rate models. Log-likelihood values, LRTs, and p-values are further displayed for Post hoc pairwise comparisons.

Trait	σ2obs	σ2common	AICobs	AICcommon	Log (Lobs)	Log (Lcommon)	LRT	p
(a) Length Measure Comparisons (n = 38)
Horn/antler length	10.71 × 10−3	3.30 × 10−3	−245.97	−81.83	132.98	46.91	172.14	<0.001
Muzzle width	4.17 × 10−3
Sperm head length	0.56 × 10−3
Sperm midpiece length	0.87 × 10−3
Sperm flagellum length	0.20 × 10−3
Post hoc pairwise comparisons	Head length vs. Midpiece length				77.96	77.05	1.81	0.18
	Head length vs. Flagellum length				106.20	101.20	1.00	<0.01
	Head length vs. Muzzle width				48.09	31.47	33.25	<0.001
	Head length vs. Weapon length				30.15	−1.58	63.45	<0.001
	Midpiece length vs. Flagellum length				97.88	88.23	19.30	<0.001
	Midpiece length vs. Muzzle width				39.77	29.08	21.39	<0.001
	Midpiece length vs. Weapon length				21.82	−2.60	48.85	<0.001
	Flagellum length vs. Muzzle width				68.02	34.51	67.02	<0.001
	Flagellum length vs. Weapon length				50.07	−0.34	100.81	<0.001
	Muzzle width vs. Weapon length				−8.04	−12.13	8.18	<0.01
(b) Mass Measure Comparisons (n = 60)
Testes mass	0.019	0.017	118.56	117.42	−55.28	−55.71	0.87	0.35
Body mass	0.015