Fig. 7
From: Hybridisation has shaped a recent radiation of grass-feeding aphids
Topology weighting reveals massive introgressed blocks. a SplitsTree [65] network of phased haplotypes based on 73,903 genome-wide SNPs for Chinese GBS samples (Additional File 7: Table S6) plus the whole genome sequences of S. avenae JIC1 from the UK and S. miscanthi LF1 from the LF_MY population. Tips are coloured by population/lineage as per Fig. 5. Three focal S. miscanthi-like lineages (WH, QD_TA and KM) and one outgroup S. avenae lineage (UK) are highlighted. b Phylogenetic trees were estimated in 50 SNP windows across all S. avenae chromosomes for all samples included in a. The bar chart summarises the average genome-wide weighting (determined by Twisst [75], see main text) of the three possible topologies between WH, KM, QD_TA and UK focal lineages. The tree with the highest weighting (topo2) corresponds to the species tree estimated with SNAPP (Fig. 5c). Alternative topologies are also highly weighted. c The distribution of topology weightings across all nine S. avenae chromosomes reveals large blocks with a different evolutionary history to the species tree. Example regions on chromosome (scaffold) 2 are highlighted with purple (predominantly weighted towards the species tree (topo2)) and pink (predominantly weighted towards topo3). d, e show SplitsTree networks of phased haplotypes for the example regions of chromosome 2 highlighted in c. For each network, the focal lineages are indicated