ancient email:

> I'm told that the Inuit usually have the shovel shaped incisors and
> that Christie Turner has done some work on that.  Apparently this
> type of tooth turns up in people whose ancestors were from NE Asia,
> and they are considered diagnostic of these human type by some.
>
> Anyone know more about this?

Syracuse Univ. physical anthro and human variation courses assert
that shovel shaped incisors are nearly universal in Asiatic humans.
This includes nearly all 'native' Americans.  Excepting probably poor
bedivviled Mr Kenniwick.

Anecdotally: a friend whose father is Japanese and mother
Anglo-American has them; a friend whose father is Polish-American and
mother is Korean has them.

It's a longitudinal groove in the back face of the incisors roughly
half the width of the tooth but somewhat variable.