It is Convergent evolution
Genetic. And it allows for more fish to be created and living freely
A(n) chemical bond forms when two atoms share one or more pair of electrons.
This can be because of their genetics. The siblings may not have inherited their parents looks, but maybe they inherited their grandparents looks, or even their aunts looks. This is all due to genetics. It's sort of the same thing, when two caucasian parents have an african-american child. That would be because somewhere along the family tree someone was african-american.
Anyways, I hope this helps!
