Question About Creationists

[libalchris]

What exactly do you mean by "the DNA sequences are very similar"? Could you clarify? All living things made up of DNA only have 4 nucleotide bases to choose from...adenine, cytosine, guanine, thymine. I wouldn't be surprised if there were "similarities" in the sequencing all living things. But that does not explain how the function of chromosomes evolved amongst various organism.

Let me be more specific. First of all, I would like to mention that the fact that all life using the same 4 nucleotides is evidence for common descent, considering there are many more could be used. Along with that, all life uses the same 20 amino acids, when there are also many many more that could have been used, providing very strong support of evolution.

Now, the similarities in the chromosomes has to do with the proteins and where they are found on the genome. In this case, when we look at the human genome vs the chimpanzee genome, based on the correspondence of different proteins in different locations on different chromosomes, we can show that each human chromosome corresponds to 1 chimpanzee chromosome (because they have the same, or similar, genes coding for the same things at the same location on the protein.

Again, in summary, each human chromsome can be found to correspond to a chimp chromosome. Now we find that one of our chromosomes (chromosome 2) has fused, when we "take apart" this chromosome we find that each of the pieces corresponds to the pairs of chimp chromosomes we were missing.

I'm sure I'm not very good at explaining this, so let me show you a diagram of chimp and human chromosomes



the left ones are humans and the right ones are chimps. You can see how similar they are, and how each human chromosme has a corresponding chimp chromosme. You see how we can tell that the 2 parts of the human corresponds to the 2 separate chimp chromosomes.

Let me emphasize real quick that this need not be the case. If there were a creator he easily could have made the chromosomes in such a way that would render common descent impossible. For example if chromosome 2 existed not as the result of a fusion (ie if we found no extra centromeres and telomeres) then common descent would be destroyed.