Table 1 General Linear Models with one of the six metabolites (mmol/l) or VLDL as response variable, species as factor (European Robin ER, Pied Flycatcher PF, Garden Warbler GW), and body energy stores (percent above lean mass, see Methods), flight duration (percentage of nighttime elapsed between evening twilight and capture, see Methods), (body energy stores)², (flight duration)², time elapsed between capture and blood sampling (time after capture; min), (time after capture)² and interactions with species as fixed factors. Interactions and quadratic terms were removed stepwise backwards if they did not reach significance at the P < 0.05 level. Sample size per species (in parentheses), estimates ± SE and significance (* p < 0.05, ** p < 0.01, *** p < 0.001) are given

Intercept

3.863 ± 0.387***

2.912 ± 0.394***

1.439 ± 0.264***

0.558 ± 0.104***

0.794 ± 0.116***

17.379 ± 0.731***

4.217 ± 4.557

Species

ER

(92)

-1.453 ± 0.165***

(78)

-0.451 ± 0.152**

(69)

-0.598 ± 0.132***

(62)

-0.310 ± 0.045***

(95)

0.463 ± 0.106***

(83)

3.492 ± 0.442***

(76)

9.383 ± 1.553***

PF

(119)

-1.122 ± 0.158***

(89)

-0.400 ± 0.147**

(79)

-0.134 ± 0.129

(71)

-0.141 ± 0.044**

(117)

0.251 ± 0.098*

(105)

2.524 ± 0.417***

(42)

0

GW

(58)

0

(51)

0

(31)

0

(32)

0

(56)

0

(57)

0

Energy stores

0.021 ± 0.006***

0.006 ± 0.006

-0.014 ± 0.005**

0.006 ± 0.002**

0.007 ± 0.004

0.006 ± 0.015

0.201 ± 0.090*

Energy stores*species

ER

-0.017 ± 0.007*

PF

-0.003 ± 0.005

GW

0

Flight duration

2.761 ± 1.212*

3.221 ± 1.103**

0.297 ± 0.226

1.458 ± 0.330***

-0.178 ± 0.109

-2.694 ± 0.683***

60.449 ± 15.443***

(Flight duration)²

-3.022 ± 1.107**

-3.005 ± 0.997**

-0.973 ± 0.307**

0

-68.539 ± 12.773***

Time after capture

-0.021 ± 0.017

-0.392 ± 0.066***

0.202 ± 0.048***

-0.011 ± 0.004*

0.005 ± 0.007

-0.087 ± 0.049

0.518 ± 0.187**

(Time after capture)²

0.22 ± 0.004***

-0.009 ± 0.003**