In that complex record of fossils, there were times when lots of stuff seemed to be dying out very quickly, and the father/mother geologists called these "mass extinctions."
在化石的复杂历史记录中， 确实有些时候很多东西 看起来很快要灭绝了， 于是，地质学家之父或之母 把这种现象叫作“物种大灭绝”。