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Table 2 Egg rejection response and latency to rejection by thrushes

From: Host responses to interspecific brood parasitism: a by-product of adaptations to conspecific parasitism?

Type of parasitism Blackbird Song thrush
  ddf F P ddf F P
CONSPECIFIC       
(R)ejection       
Breeding density 105 5.31 0.02 41 3.01 0.09
Clutch 101 1.43 0.24 39 0.79 0.38
Nest stage 98 1.00 0.40 35 0.67 0.57
Laying date 97 0.92 0.34 38 0.63 0.43
Latency to (r)ejection       
Breeding density 48 2.94 0.09 11 1.22 0.29
Clutch 44 0.19 0.66 11 5.13 0.04
Nest stage 41 0.70 0.56 8 1.38 0.32
Laying date 47 0.64 0.43 7 0.05 0.82
INTERSPECIFIC       
Ejection       
Geography 455 7.30 0.0008 216 0.59 0.55
Egg model 455 29.57 <0.0001 216 20.40 <0.0001
G*E 446 1.11 0.33 206 0.24 0.79
Clutch 449 0.40 0.53 208 0.70 0.40
Nest stage 455 5.41 0.001 213 2.31 0.08
Laying date 448 0.04 0.85 212 1.63 0.20
Latency to ejection       
Geography 308 0.16 0.86 101 2.53 0.08
Egg model 308 29.87 <0.0001 101 0.33 0.57
G*E 300 2.53 0.08 95 1.33 0.27
Clutch 303 0.29 0.59 101 7.99 0.006
Nest stage 308 3.86 0.01 98 1.97 0.12
Laying date 302 0.05 0.82 97 0.40 0.53
  1. Response to conspecific egg in blackbirds includes nest desertion (i.e., abandoning the whole clutch), together with egg ejection (i.e., selective removal of a foreign egg), as rejection response to parasitism (see Results, and the Additional file 1: Appendices). All other responses (conspecific in song thrush, and interspecific in both thrushes) exclude desertion from analyses (for complete results, see Additional file 1: Appendix 2). Test statistics and P-values for non-significant terms are from backward elimination procedure just before the particular term (being the least significant) was removed from the model. Results of significant predictors from final models are in boldface. For effect sizes see Figures 2, 3 and Results. G = geography, E = egg model.