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?
Biogenetic law
Haeckel’s biogenetic law states that “Ontogeny repeats phylogeny”. Ontogeny is the life history of an organism while phylogeny is the evolutionary history of the race of that organism. In other words, an organism repeats its ancestral history during development.
Therefore, during embryonic development, the mammalian heart first takes the form of fish, then frog and finally mammal.