I think this means basically that they're all sharks and they've come from a common ancestry. If you look at nucleotide diversity, which is more genetics that are passed on through parents, was an order of magnitude less diversity than other shark species.
私が思うにこれは それらはどれもサメで共通の祖先から 派生しているのではないでしょうか 両親から伝えられる遺伝子の ヌクレオチドの多様性を見れば ウバザメは 他の種類のサメと比べて