Re: Questions about endocasts of fossil hominid brains

GRMorton@aol.com
Thu, 4 Jan 1996 00:18:52 -0500

Bill Hamilton wrote:
>>I presume an endocast is a cast of the inside of the skull (which leaves
the question: how do the extract the cast after making it? Maybe they use a
layer of flexible material which when it solidifies can be withdrawn
through an opening? Surely they don't break the skull. Or maybe they use
partial skulls?)

My (main) questions are: What do endocasts show? Do they actually show the
shape of the brain? Down to what level of detail? Or do they simply show
the shape of the skull which contained the brain, in which case some details
about brain structure are lost. If they show the shape of the brain, how can
this be? I thought soft parts generaly just decayed,
leaving only hard parts like bones to fossilize.<<

I am not expert on this, I presume Jim Foley is a better source of info but I
don't see that he has answered. You can pour liquid latex into an object,
let it harden and then pull it out. From that you can make a better, more
solid molding of the interior of an object.

There may be better chemicals than latex nowadays.

As to the soft parts of the brain being shown, the interior of the skull
molded itself around part of the brain. I don't know quite how this works
but that is the observation. And I am sure that some details are lost.

Jim Foley, any corrections?

glenn