Another step of our pretty girl who will live a hundred miles an hour this long moment towards another "substance" by the unsuspected force of a young female in heat. "Estrus is the phase when copulation occurs and the female is fertile. It is noted that the female will 'stand' for the male with her tail averted. This change in behavior is a sign that the female has come into the estrus phase. If inattentive, she will paw, rub, straddle or even mount the male."