Gaps in the geographic range of the species may have been caused by earthquake uplift events such as the 1855 Wairarapa earthquake. However, historic uplift (800 - 1400 years before present) in the Akatore fault zone does not seem to have caused any long term disruption in the genetic diversity of "D. willana", in that region. This result suggests that the subtidal "D. willana" may not die-off completely due to earthquake uplift events.