title: WGS of four Parus major females
design: Library preparation and sequencing of the four samples used in this study was performed by Novogene Company Limited (UK). The genomic DNA was randomly fragmented by sonication, after which DNA fragments were end polished, A-tailed, ligated with the full-length Illumina adapters, and followed by further PCR amplification with P5 and indexed P7 oligos. These PCR products as the final construction of the libraries were purified with AMPure XP system. Libraries were then checked for size distribution by Agilent 2100 Bioanalyzer (Agilent Technologies, CA, USA) and quantified by real-time PCR (to meet the criteria of 3 nM). Libraries were sequenced on one lane from both ends of the 150bp fragments (i.e. paired-end) using a NovaSeq 6000. See Table S1 for unique read counts per sample.