Embryonic Signals and Maternal Recognition

摘要: In the first paper of this volume Professor Amoroso argues that viviparity is a reproductive stratagem has evolved many times in widely separated taxonomic groups animal kingdom. Retention embryos within body and birth living young occurs among representatives all classes vertebrates except birds, invertebrates. light wide distribution it not surprising solutions to problems posed by evolutionary innovation are numerous (Amoroso et al., 1979). eutherian marsupial mammals, which become preferred mode reproduction, prominent role emerged for corpus luteum. Progesterone secretion luteum essential establishment gestation eutherians so far studied, mechanisms have result converting female system from cyclic pattern, oscillations progesterone estrogen occur, noncyclic dominant. The time when transformation an early indication maternal recognition pregnancy (Short, 1969), recent studies focused on nature embryonic factors signal event (Heap Perry, 1977).