IS THAT A PLASTER CAST OF WHAT WAS FOUND, WITH PLASTER ADDED TO MAKE THE SKULL APPEAR COMPLETE?
The normal practice is to fill in missing pieces of a skull with a different color material. This shows pretty clearly in the picture I posted in #227.
When casts are made--most are now plastics rather than plaster--the areas missing in the original are also color coded in the same way. Usually no attempt is made to fill in detail in these missing areas--just blank plaster or plastic.
This shows pretty clearly in the specimen below; the gray areas are missing.
Fossil: KNM-ER 3733 Site: Koobi Fora (Upper KBS tuff, area 104), Lake Turkana, Kenya (4, 1)Discovered By: B. Ngeneo, 1975 (1)
Estimated Age of Fossil: 1.75 mya * determined by Stratigraphic, faunal, paleomagnetic & radiometric data (1, 4)
Species Name: Homo ergaster (1, 7, 8), Homo erectus (3, 4, 7), Homo erectus ergaster (25)
Gender: Female (species presumed to be sexually dimorphic) (1, 8)
Cranial Capacity: 850 cc (1, 3, 4)
Information: Tools found in same layer (8, 9). Found with KNM-ER 406- A. boisei (effectively eliminating single species hypothesis) (1)
Interpretation: Adult (based on cranial sutures, molar eruption and dental wear) (1)
See original source for notes:
Source: http://www.mos.org/evolution/fossils/fossilview.php?fid=33