Artificial selection reveals the energetic expense of producing larger eggs

Table 3 Difference between the selection lines in body mass (BM), metabolic rate (RMR) and oxidative damage (ROMs) according to breeding status

Trait	Model	Line		Status		Line x Status		Replicate		Age		Tarsus Length		Body Mass		RMR
		χ ²	P	χ ²	P	χ ²	P	χ ²	P	χ ²	P	χ ²	P	χ ²	P	χ ²	P
BM	a	-	-	-	-	5.29	0.021	0.19	0.665	0.88	0.347	10.73	0.001	-	-	-	-
RMR	a	-	-	-	-	4.82	0.028	0.21	0.646	0.00	0.947	2.17	0.141	-	-	-	-
	b	0.16	0.688	30.57	<0.001	1.10	0.294	0.12	0.734	0.45	0.503	-	-	30.01	<0.001	-	-
ROMs	a	0.06	0.802	1.85	0.174	3.08	0.079	3.08	0.079	2.00	0.158	1.07	0.300	-	-	-	-
	b	0.28	0.596	1.87	0.172	3.20	0.074	3.44	0.064	1.69	0.193	-	-	0.02	0.880	-	-
	c	0.55	0.459	0.27	0.607	3.19	0.074	3.67	0.056	1.68	0.195	-	-	-	-	1.14	0.287

Significant results are displayed in bold. For metabolic rate and oxidative damage, several models were run, including a) tarsus length, b) body mass and c) metabolic rate as covariates. In all models df = 1

ISSN: 1742-9994