 The patterns of diversity found in its mitochondrial DNA are consistent with the repeated splitting and merging of its populations as geographical barriers were alternately formed and inundated.The most recent of these barriers was a land bridge across the Torres Strait that reopened only some 6,000 years ago; as a result, significant genetic separation exists between the sharks found off Western Australia and the Northern Territory and those found off Queensland.The pigeye shark is a very robust-bodied species with a short, broad, and rounded snout.