Table 2. Analysis of the influence of age at first reproduction and relative testes mass on female median lifespan and aging rate.

			Median lifespan						Aging rate
	Independent variables	k	λ	R2	Deviance	AICc	ΔAICc	wi	λ	R2	Deviance	AICc	ΔAICc	wi
All species(n = 48 and 51)	Constant	3	0.86	0.00	103.22	105.32	27.97	0.00	0.50	0.00	174.68	176.77	10.98	0.00
	Age at first reproduction	4	0.57	0.51	72.04	77.35	0.00	0.88*	0.08	0.31	160.5	165.79	0.00	0.82*
	Body mass	4	0.63	0.34	85.48	90.78	13.43	0.00	0.38	0.05	171.34	176.64	10.85	0.00
	Testes mass+Body mass	5	0.63	0.34	84.50	93.15	15.80	0.00	0.38	0.03	171.34	179.95	14.16	0.00
	Age at first reproduction+Testes mass+Body mass	6	0.48	0.52	66.76	82.88	5.53	0.06	<0.001	0.37	157.38	169.43	3.64	0.13
	Age at first reproduction*Testes mass+Body mass	7	0.48	0.55	67.08	82.78	5.43	0.06	<0.001	0.37	156.32	171.91	6.12	0.04
All species(n = 50)	Constant	3							0.67	0.00	156.42	158.51	13.41	0.00
	Age at first reproduction	4							<0.001	0.39	139.8	145.10	0.00	0.87*
	Body mass	4							0.44	0.06	153.32	158.61	13.51	0.00
	Testes mass+Body mass	5							0.43	0.04	153.3	161.91	16.81	0.00
	Age at first reproduction+Testes mass+Body mass	6							<0.001	0.39	137.28	149.34	4.24	0.10
	Age at first reproduction*Testes mass+Body mass	7							<0.001	0.38	136.74	152.37	7.27	0.02
Carnivores(n = 14 and 15)	Constant	3	<0.001	0.00	17.90	20.27	0.00	0.43*	0.79	0.00	44.26	46.61	0.00	0.66*
	Age at first reproduction	4	<0.001	0.17	14.12	20.36	0.09	0.41	0.30	0.11	43.24	49.39	2.78	0.16
	Body mass	4	<0.001	0.03	16.36	22.61	2.34	0.13	0.80	0.00	44.26	50.41	3.80	0.10
	Testes mass+Body mass	5	<0.001	0.00	16.00	26.79	6.52	0.02	0.81	0.09	40.54	51.08	4.47	0.07
	Age at first reproduction+Testes mass+Body mass	6	<0.001	0.09	12.84	28.99	8.72	0.01	0.40	0.13	39.7	55.38	8.77	0.01
	Age at first reproduction*Testes mass+Body mass	7	<0.001	0.17	10.18	32.87	12.60	0.00	<0.001	0.31	38.18	59.92	13.31	0.00
Artiodactyles(n = 19)	Constant	3	0.65	0.00	29.86	32.12	9.54	0.01	<0.001	0.00	38.64	40.90	0.00	0.60*
	Age at first reproduction	4	0.83	0.49	16.72	22.58	0.00	0.73*	<0.001	0.04	36.76	42.63	1.73	0.25
	Body mass	4	0.75	0.14	26.04	31.91	9.33	0.01	<0.001	0.00	38.5	44.35	3.45	0.11
	Testes mass+Body mass	5	0.74	0.16	24.32	34.19	11.61	0.00	<0.001	0.00	37.16	47.03	6.13	0.03
	Age at first reproduction+Testes mass+Body mass	6	0.87	0.52	13.42	24.77	2.19	0.24	<0.001	0.00	35.52	49.86	8.96	0.01
	Age at first reproduction*Testes mass+Body mass	7	0.88	0.53	12.10	31.50	8.92	0.01	<0.001	0.00	34.48	53.89	12.99	0.00

We compared models based on AICc and w_i (see Material and methods section). K represents the number of parameters in the model, R² corresponds to the adjusted R² and Δ AICc represents the difference of corrected Akaike’s with that of the best models (*).

¹For the moose, Alces alces, the body mass extracted from the testes mass source was really high (789 kg, [81]). However, results were unchanged when we used body mass from another source (323 Kg, [82]).