Vasanas

In Srimad Bhagavatam, we see that Jadabharata was born as a deer because in his earlier birth, he had so much love to the deer that he petted.
Madhava Swami was an attendant of Bhagavan Ramana. He was born as peacock in his next birth. He lived his life devoid of lust. He was a true celibate (‘uthama brahmachari). Amongst birds, it is only peacock that has least lust.
‘Keerai paatti’, yet another devotee of Bhagavan Ramana was reborn as a cow. She possessed the ‘vasana’ of giving ‘keerai’ (greens) to all. It is only the cow that has a mother’s heart, that is, ‘vãtsalya’ (compassion). So, she acquired that sort of a birth. The cow gives milk to so many children.
It is ‘vasanas’ that is the reason for rebirth and the kind of birth.