Does every human brain have the same shape?
No, not at all--or not necessarily; different sulci &amp; gyri may be different shapes--this is one of the reasons why individual brains are transformed or normalized into standard space in group analysis of MRI data (see here for a good basic explanation of how &amp; why this is done). In some cases canonical landmarks may be missing entirely--famously, an autopsy showed Albert Einstein to have quite anomalous anatomy in the area of the frontal operculum or Sylvian fissure.