How does the reproductive system of avian and mammalian female differ from each other?

The reproductive system of avian females primarily consists of a single functional ovary and oviduct, where eggs are formed and laid in a shell, allowing for external fertilization and development. In contrast, mammalian females typically have two ovaries and a more complex reproductive system, including a uterus where fertilized eggs implant and develop internally, leading to live births. Additionally, mammals often have a menstrual or estrous cycle, while birds have a more seasonal reproductive cycle. These fundamental differences reflect adaptations to their respective reproductive strategies and environments.