Falling coconuts are a major cause of death in Island countries (it's true, no bullshit)
Having said that, this phenomena has phased out all of the weak, so the strong that survive, that also go on to become fighters already have that thick bone/skull structure that makes them very durable.
By the way serious question... Do Filipino's count as Polynesian or Asian, or even both?
I ask this in regards to Filo fighters with awesome chins like Lawler, Yagin or Celeste (who I'm sure can take a great shot to the chin if u know what I mean, *wink, *wink) but not so much Vera or Munoz