The first type of evidence that strongly supports Darwin's first hypothesis:

Common Genetic Codes (Arbitrary Similarity)

   All organisms (with some minor exceptions) use the same genetic code. Genes cause amino acids to form. The total sequence of genes in a human’s body is different from the sequence in a frog. But the striking fact is that the gene that codes for a particular amino acid in a frog codes for that very same amino acid in humans. The code is arbitrary and there is no functional reason why it has to be the way it is.

   If species arose independently of each other, we would expect them to use different genetic codes. But if these species all trace back to a common ancestor (common cause), it is to be expected that they will share the same genetic codes.

   The common cause hypothesis is more plausible according to the >>> The Surprise Principle.