Gut microbiota in two recently diverged passerine species: evaluating the effects of species identity, habitat use and geographic distance

Table 2 Db-RDA analyses testing the effects of species identity (common nightingale vs. thrush nightingale), geographical region (sympatry vs. allopatry) and their interaction on the gut microbial composition

	Dataset	Explanatory variable	p-value	Adjusted – R²
Bray–Curtis distance	Complete	Species	0.085	0.139
		Region	0.087
		Species × region	0.034
	Sympatry	Species	0.055	0.088
	Allopatry	Species	0.071	0.090
	CN	Region	0.098	0.158
	TN	Region	0.014	0.049
Jaccard distance	Complete	Species	0.076	0.106
		Region	0.096
		Species × region	0.043
	Sympatry	Species	0.078	0.077
	Allopatry	Species	0.051	0.061
	CN	Region	0.096	0.101
	TN	Region	0.069	0.056

Analyses were performed on both Bray-Curtis and Jaccard distance matrices, which were the response variables. We also ran the db-RDA analyses to test for the effect of species separately in sympatric and allopatric regions and to test for the effect of region separately in each species. The significance of the models was assessed by a permutation-based ANOVA, where individual identity variation was taken into account during the permutation procedure. Significant p-values are marked in bold. CN stands for common nightingale and TN for thrush nightingale

ISSN: 2730-7182