The image shows the evolution of the sign SAG "head" (Borger nr. 115, U+12295). 

the pictogram as it was drawn around 3000 BC.
the rotated pictogram as written around 2800 BC.
the abstracted glyph in archaic monumental inscriptions, from ca. 2600 BC
the sign as written in clay, contemporary to stage 3.
late 3rd millennium (Neo-Sumerian)
Old Assyrian, early 2nd millennium, as adopted into Hittite.
simplified sign as written by Assyrian scribes in the early 1st millennium
This file was derived from: SAG.png:
Original: Dbachmann Vector:  Rehua (talk)