Chicken
Chickens include easily adapted animals in places, provided the availability of food is abundant. Chickens that have been domesticated today are easy to tame so as to facilitate the maintenance. The unique feature of chickens is in their gynecological system regulated by the hormonal system. If there is a disturbance in the physiological function of the body, the hens can change sex into males because adult chickens still have a dormant ovotestis (immobile) and at any time can be active again.