ikefalcon

ikefalcon t1_j508nej wrote

As the previous commenter said, human chromosome 2 has nearly identical sequences to chromosomes 2a and 2b in the other great apes. It’s believed that human ancestors like Neanderthals had 23 chromosome pairs like humans.

Also, chromosomes usually have 1 centromere (center link between pairs of chromatids) and 2 telomeres (basically end caps of the chromosome). Human chromosome 2 has a vestigial (unused due to no longer being needed) extra centromere and 2 vestigial telomeres found inside the chromosome sequence.

This is pretty good evidence that there used to be 2 chromosomes before they fused together.

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