Chromosome 2: Two Chromosomes
Possibly one of my favorite examples of why evolution is practically an unquestionable fact lies in a genetic novelty. As a large proportion of you will know, humans have 23 pairs of chromosomes. What less of you will probably know is that chimpanzees, gorillas and other members of family Hominidae (to which we also belong) all have 24 pairs of chromosomes. So where did that extra chromosome go? The answer lies in a quick glance at chromosome 2 which is the second largest human chromosome, storing 8% of all our genes. Chromosome 2 has several odd features such as the existence of the remnants of a second centromere along with extra telomeres (the regions at the end of a chromosome). The sequence of base pairs on chromosome 2 also corresponds almost exactly with two other chromosomes found in other members of hominidae which is fairly strong evidence for the fusion of two chromosomes at some point in our past. Chromosome 2 has also been linked to increased intelligence along with also being the chromosome that carries the genes for autism, synesthesia and amyotrophic lateral sclerosis (ALS) which is better known as the motor-neuron disease that Stephen Hawking has.