The Mom Factor
Instinctual behavior is something that human beings have to work to understand within ourselves to be able to use or avoid when fulfilling our Godly mission. The Torah teaches us how to interact properly with the world around us in light of instinctual behavior found in other species.
The Torah instructs us to send away a mother bird, time and time again if we happen to find her sitting on her young. The Torah is particular in telling us to send her away versus telling us not to take her along with her young.
A bird, whether a mother or not, avoids being caught by attempting to fly away. A convenient opportunity in which to capture a bird would be when a mother is sitting on her young. Her motherly instinct instructs her to remain with her young, overriding her instinct to flee from being caught. A sensitivity that can be taken away from this mitzvah is to not take advantage of a mother when she is sitting on her young.
"You shall not take the mother on the young." Deuteronomy 22:6, from this week's Torah portion, Ki Teitzei, Deuteronomy 21:10-25:19
* Based on Rashi, the Gur Aryeh and Rabbi Foreman