Evolution Is Not Proven

Con argues that since fossilization is a rare occurrence, that “gives reason for the "underepresented" Precambrian life.” This does not refute my argument. In making this statement, Con has to assume that the supposed “underpresented [sic]” Precambrian life actually existed! The problem is the lack of evidence of transitionals between creatures like the mollusk and bacteria. Con has thus far only provided excuses for why they aren't found, instead of proving that they actually existed. It's one thing to excuse the lack of fossil evidence for these creatures, but to successfully refute my case, he's going to have to use a different type of evidence to prove that millions of transitionals between bacteria and mollusks actually existed. Pro is trying to use an argument from ignorance; assuming that the absence of evidence is evidence of absence. Basically, he argues that “there's evidence” that a geochemical change in ocean composition resulted in “A LOT” more calcium and mollusks had the genes for building a shell but until this geochemical change, they couldn't build a shell. So my opponent is trying to convince everybody reading this debate that mollusks went from having a shell, to not having a shell in a single generation. However, since he is careful to say that “there's evidence” for his claim, instead of saying that “it's proven” or “there's conclusive evidence”, his argument does not damage my case and I'm going to drop it. This is again simply semantics not a rebuttal. Con repeats an already-refuted argument, in an attempt to explain why no transitionals between mollusks, and sponges or worms or bacteria, have been found: “soft bodied creatures only fossilize in extremely unusual environmental conditions as in VERY RARE.” I've already pointed out how not only does this fail to explain why the millions of shelled transitionals haven't been found (if they ever existed), it's not sufficient to prove Evolution (as I defined it in the first round). Excusing the lack of evidence for something does not prove it, like I demonstrated with my little analogy. Con again tries to explain the sudden appearance of 10 major phylum without plausible links to mollusks, sponges, and worms by mentioning Punctuated Equilibrium. As I said in the previous round, this is a dead-end argument. Punctuated Equilibrium does not explain the sudden emergence of new phyla. I don't think Con understands what the term even means. Pro doesn't seem to understand punctuated equilibrium; punctuated equilibrium and although pro says he's refuted it, all pro has said about it is that it it doesn't explain the emergence of new phyla; pro has given no reason why it wouldn't work. As “proof” that all life descended from a common ancestor, he mentions another experiment involving bacteria that remained bacteria throughout many generations, although they gained the ability to survive higher temperatures. He seems to be aware that this isn't convincing: “Since many people claim those are not valid evidence because of the difference between a single cell and a multicellular organism here's an example with mice:” However, even his mouse experiment didn't “prove” that mollusks descended from bacteria, so this is another dead-end argument. Actually the long term E.coli Experiment IS proof of common descent; here's a quote about that: Lenski chose an E. coli strain that reproduces only asexually, without bacterial conjugation; this limits the study to evolution based on new mutations and also allows genetic markers to persist without spreading except by common descent. Pro's definition of evolution was common descent and the E. Coli experiment is proof of common descent. Therefore I have just proven my case.