5. cranium

The cranium is part of the skull that holds the brain in a large cell, which is called the cranial vault. As the brain grew the head had to grow as well, so evolution now made it that most brain growth was done outside the womb. The only problem with this was that now humans were dependent on their mothers for the first six years of their life.

Information from: Dataface: [1] Manual: pg. 20, 23