Whole genome sequencing of the northern elephant seal: 6012
The extracted DNA was sheared into 50-800 bp fragments.  Fragments ranging from 150 bp to 500 bp were selected and treated with T4 DNA polymerase (Enzymatics, Beverly, USA) to obtain blunt ends. T-tailed adapters were then ligated to repair these blunt ends. PCR amplification was performed and AMPure XP beads (Agencourt, Beverly, USA) were used to purify the PCR products. We sequenced the samples with a pair-end read length of 100 bp.