[Avodah] Birds vs waterfowl - daf yomi 56b

[Micha Berger]

On Mon, Aug 22, 2011 at 03:59:09PM -0400, Hankman wrote:
: In the daf yomi at the top of 56b, Rav Shizvi says "hani avzi didan
: ke'oif shel mayim damyan." Rashi explains, "ho'yil vetomid hain bamayim,"
: meaning and therefore their krum is rach as well - just like waterfowl.

Just thinking out loud...

Wouldn't skull structure be largely determined by beak, and thus by
diet? In which case, I could see why birds that fill similar niches
would have similar skulls, regardless of taxonomy. See also the first
Rashi on 56b, which appears to be saying the difference is in the
placement and size of the hole of the skull.

Admittedly, that doesn't necessarily translate to differences in
the meninges, but it would explain the differences in din.

Tir'u baTov!
-Micha