If you give a design problem to ten different engineers to solve, chances are you will not get ten different solutions. In fact, you are likely to end up with ten solutions that look very much alike.
Now suppose 10,000 years from now someone found your ten sheets of problems, each with the design solutions offered by the ten engineers. Since they are practically the same, this person might conclude that each of the solutions was offered by the same person. He would account for their differences by saying that as each solution was tried, better ideas were developed. He would conclude that the solution most familiar to his own day was the final and most advanced solution.
When evolutionists compare creatures like humans with apes, noting the similarities, they are falling into the same trap as our theoretical researcher from the future. Certainly there are some similarities between humans and apes. However, the structure of the human eye is most similar to the eye of the octopus! The general pattern of the functional structure of hemoglobin in human blood differs by only one atom from the chlorophyll found in plants. And the protein in human milk is most like the juice of the soybean plant.
None of these comparisons offers any evidence for evolution. What they illustrate is that any good designer will solve similar problems with similar designs – they offer evidence that the creation is the work of a wise and powerful Designer!