A Curved Shofar

The Mishnah (Rosh Hashanah 26b) has a dispute between the Tanna Kamma (the first, anonymous opinion) and R. Yehudah regarding the shofar blown on Rosh Hashanah. According to the Tanna Kamma, the shofar used on Rosh Hashanah should be straight and from a ya'el. According to R. Yehudah, it should be from a male (and curved). The Gemara asks why the Tanna Kamma prefers a straight shofar and R. Yehudah a curved shofar and answers that according to the Tanna Kamma on Rosh Hashanah people need to straighten their minds and according to R. Yehudah they need to bend themselves in prayer.

Another Gemara (Rosh Hashanah 16a) states that we blow a ram's horn in order to remember the ram of Akedas Yitzchak. Based on this, the Rambam (Hilkhos Shofar 1:1) rules that a shofar must be from a ram and must be curved. But if that is the case, why does the Gemara answer that according to R. Yehudah we blow a curved shofar because people need to bend themselves in prayer. The Gemara should have answered that we need to remember the ram of Akedas Yitzchak.

R. Eli Shulman (Yesamach Av 1:1) answers based on a debate in Tosafos (Rosh Hashanah 26b sv. shel) over what a ya'el is. According to the Arukh, a ya'el is a female sheep while according to Rashi it is an ibex (=steinbuck). According to the Arukh a ya'el and an ayil -- a female and male sheep -- are of the same species as the ram of the Akedas Yitzchak and both are reminiscent of it (a ram is a kind of sheep -- link). However, a male usually has a curved horn while a female usually has a straight horn. Therefore, remembering the Akedas Yitzchak is not sufficient to explain why we need a curved or straight horn because both are sufficient to remember it. That is why the Gemara needs to arrive at a different answer to that question.