Table 2 Results of ANOVA tests using factor scores from the first three principal components of a PCA to test for differences in passerine uropgyial gland microbiota depending on season, migration distance, taxonomic family, and species (see Table S3 for factor loadings)
| Â | df | Sum of squares | Mean sum of squares | F | P |
|---|---|---|---|---|---|
PC1 | |||||
Season (fall, spring) | 1 | 857 | 857 | 21.6 |  < 0.0001 |
Migration (inter, intra) | 1 | 707 | 707 | 17.8 |  < 0.0001 |
Family | 10 | 1265 | 127 | 3.2 | 0.0006 |
Species | 6 | 352 | 59 | 1.5 | 0.183 |
Residuals | 454 | 18,013 | 40 | – | – |
PC2 | |||||
Season (fall, spring) | 1 | 1921 | 1921 | 143.9 |  < 0.0001 |
Migration (inter, intra) | 1 | 47 | 47 | 3.5 | 0.062 |
Family | 10 | 1217 | 122 | 9.1 | 0.0009 |
Species | 6 | 102 | 17 | 1.3 | 0.268 |
Residuals | 454 | 6062 | 13 | – | – |
PC3 | |||||
Season (fall, spring) | 1 | 186 | 186 | 13.6 | 0.0002 |
Migration (inter, intra) | 1 | 57 | 57 | 4.2 | 0.042 |
Family | 10 | 2006 | 201 | 14.7 |  < 0.0001 |
Species | 6 | 291 | 48 | 3.6 | 0.002 |
Residuals | 454 | 6175 | 1 | – | – |