Question

are birds in evolutionary specialized for reproduction? Compare them to mammals and reptiles to make an argument for you Answer.

2 paragraphs needes. so, I need details please.

Answer 1

Both birds and reptiles have a common opening called cloaca which is required for digestion, excretion and reproduction but in mammals there are separate openings for excretion and reproduction. Mammals have uterus which are absent in reptiles and birds. Species producing large number of offsprings have two uterus while species producing few offspring have one uterus. Also there are difference in sperm transfer mechanism. For transfer of sperms the cloaca of the birds are positioned opposite to each other while in mammals it is through the penis. Reproduction of birds is similar to theropod dinosaurs like Oviraptors and Troodontids. All modern birds have a single functional ovary and they incubate their eggs through direct contact. Except birds, in all vertebrate classes oviparity and viviparity exist in a genus or species. Transition from oviparity to viviparity is related to changes in oviduct structure, placental connection and glandular activity.