Fig. 1

Intergenomic Gene Transfer (IGT) among the three genomes in four cotton species surveyed. a A model of four directional IGT events among three genomes where the arrow width represents the abundance of transfers in that direction. b Length of four directional IGTs among the three genomic compartments in four cotton species. Cp: chloroplast; Mt: mitochondrion; Nu: nucleus. The left scale bar represents the length (kb) of sequences transferring into mitochondrial genomes from nuclear (the lightest grey bars) and chloroplast genomes (the lighter grey bars); while the right scale bar denotes the length (kb) of sequences transferring into nuclear genomes from mitochondrial (the dark grey lines) and chloroplast genomes (the black lines). The horizontal axis lists four cotton species, G. raimondii, G. arboreum, G. hirsutum, and G. barbadense