In the developmental history of mammalian heart. It is observed that it passes through a two chambered fish like heart, three chambered frog like heart and finally four chambered stage. To which hypothesis can this above cited statement be approximated?
Answers
Answer:
Haeckel proposed biogenetic law which states that ontogeny repeats phylogeny. Here, ontogeny refers to life history of an individual and phylogeny is the history of evolution of the individual. Therefore, all organisms recapitulate evolutionary history of their race in abbreviated form during their development. Development of complex four chambered heart of mammals go through two chambered tube like heart of fishes, three chambered amphibian heart and then becomes four chambered structure. Presence of same basic plan during embryonic development of vertebrates proves their common ancestry and the evolutionary sequence. It is established that fishes served as progenitor or amphibian which in turn gave rise to reptiles. Reptiles diversified into birds and mammals. This makes option A correct.