IE linguistic gender and the number 0

[Adela or Alain Sandness Leblanc]

Dear list members,

Could someone please recommend to me sources which would detail current
understandings regarding the following:

1.    What is the process by which, and the context within which, the
indo-european linguistic genders "animate" and "inanimate" evolved to become
the three linguistic genders we have in Vedic?  I am particularly interested
in the movement from "inanimate" to "neuter".

2.    What is the historical context within which Indian philosophers first
developed the concept of the number zero?

I thank you in advance for your assistance.

Adela Sandness

Associate Researcher
Faculty of Religious Studies
McGill University