Human Chromosome 2: a strong case for Evolution and a common ancestor

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Humans have 23 pairs of chromosomes. According to Evolution our closet common ancestor is the Chimpanzee. At the molecular level, we know our DNA sequence is 96% identical to chimpanzees Ref. However, all great apes (Chimpanzees, Gorillas and Orangutans) have 24 pairs of chromosomes. So, if we share a common ancestor how is it that we humans have 23 pairs of chromosomes and Chimpanzees and the other great apes have 24 pairs?

The answer is that somewhere during our human evolution two of our ancestral chromosomes fused to form a single chromosome. Scientist have discovered that this chromosome is human chromosome 2.

The evidence is very compelling.

Human Chromosome 2 is the second-largest chromosome (Chromosome 1 being the largest). If you look at the sequences of human chromosome 2 it has almost identical sequences in the Chimpanzee genome, but the sequences are found in two separate chromosomes (2A and 2B)

Chromosomes have a structure in the center called a centromere and normally chromosomes have only 1, but human chromosome 2 there are 2 sets of centromere sequences.

Another hallmark of chromosomes are sequences found at the ends of chromosomes are called telomeres. Normally there are only 2 telomeres sequences at the ends of chromosomes. However, in human chromosome 2 there are telomere sequences at the ends, but also near the center as a result of an ancient telomere to telomere chromosome fusion.

I feel this is one of the strongest pieces of evidence for humans and chimpanzees having a common ancestor.

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link to PNAS paper