title: SHfxSDm F2  fast-growing
design: F2 hybrid clutches  were hatched together in petri dishes, and individuals scored for date of  metamorphosis into copepodid stage, and each frozen separately. After ~3000  individuals were scored, the 10% fastest were pooled for library prep and  sequencing. Library was prepared using the Illumina Nextera kit, with gel  size-selection in the range 350-500bp.