Muscular movement is the correct answer
That most supports what scientists call the impact theory
Although the answer to this question remains uncertain, one theory is that an ancient land bridge may have allowed fauna from what is now China to reach Java. The theory is that the present-day Philippine Islands once formed part of a land bridge between mainland China and present day Java. This allowed vertebrates from the Chinese mainland to colonise Java. Supposedly, this occurred around the Pleistocene.
Egg proteins are necessary for an embryonic development
