1)
Why does the Torah write "Bas ha'Ya'anah"?
1.
Chulin 64b: In order to incorporate in the Isur the eggs of a Tamei bird.
2.
Da'as Zekenim, Hadar Zekenim and Rosh and Riva (in Vayikra 11:15): Because when the ostrich is mature, its flesh is hard [like iron (since it eats iron - Riva), and it is only its young that are edible.
