Table 2.

Detection of the nine previously studied SNP60 hybrid individuals at a structure assignment threshold of 0.25 (see Table1)

	Individual	Level	Type
Detected	7	1st	Recent
	2	2nd	Recent
	5	3rd	Recent
	1	4th	Recent
	3	2nd	Recent
Not detected	9	3rd	Advanced
(type II error)	6	2nd	Advanced
	8	2nd	Advanced
	4	5th	Advanced

Individual numbering corresponds to Goedbloed et al. [21]. The level of introgression is based on the number of introgressed domestic alleles per individual and expressed as being equivalent to the number of generations since hybridization according to simulations [21]. The type of hybrid (recent versus advanced generation) is distinguished based on the genomic distribution of introgressed alleles (clustered or spread out respectively) [21].