Megabrain Project 
 Conjoined twins 
One possible way of getting a larger human cranium involves conjoined twins who are joined at the head.

A few pictures illustrate the phenomenon:

In most cases these represent severe developmental abnormalities. However it seems possible that embryological manipulations could increase the size of the human cranium dramatically - in a manner that is not possible with interventions after birth.


Tim Tyler | Contact | http://megabrain.timtyler.org/