What is the strongest evidence for evolution?

What is the strongest evidence for evolution?

There are countless thousands of evidences for evolution which are equally powerful and equally undeniable.

Here is one of them, evidence from embryology:

Common traits in embryos. Humans, dogs, snakes, fish, monkeys, eels (and many more life forms) are all considered "chordates" because we belong to the phylum Chordata. One of the features of this phylum is that, as embryos, all these life forms have gill slits, tails, and specific anatomical structures involving the spine. For humans (and other non-fish) the gill slits reform into the bones of the ear and jaw at a later stage in development. But, initially, all chordate embryos strongly resemble each other.

In fact, pig embryos are often dissected in biology classes because of how similar they look to human embryos. These common characteristics could only be possible if all members of the phylum Chordata descended from a common ancestor.

http://evolutionfaq.com/articles/five-proofs-evolution