It is really funny to see people of unsound logic make hasty and anti-scientific conclusion.

C'mon, con-substance at the DNA level is a must for any designer to create a biosphere of vast diversity, since it is essential for carnivores to share the fundamental material and inf0rmational commonality to permit a food chain.

Just think about eating rocks and mud, that is not going to work for life.

A rich diversity of biosphere will unavoidably mean that some life f0rms are very similar. How similar?

Let's presume that the dis-similarity between the highest and lowest f0rms of life is 99%. Let's further assume that the gap between species and genius has to be at least 1%, then, we end up with only 99 incremental grades of life f0rms. But we have tens of millions, not counting the majority that became extinct in geological history. Why the discrepancy?

It follows logically that the 99 incremental nodes of life must each have a great multitude within and between them.

Thus, the minor difference should be of no surprise at all.