Reading an interesting article about DNA at the moment. As most people know DNA is organised in the nucleus of our cells in structures called Chromosomes (see picture above). Since DNA is encoded information about how to build brains and bodies then common sense might suggest that the smarter or more advanced you are as a species then the more chromosomes will be required? However, cell biology being what it is (slippery) this is not the case, and it's somewhat of a mystery why.
Here are some numbers around chromosomes, they're quite surprising..
Potato: 48 chromosomes
Chimps: 48 chromosomes
Rats: 21 chromosomes
Fruit fly: 8 chromosomes
Apple: 17 chromosomes
Giraffe: 62 chromosomes
Hermit crabs: 254 chromosomes
Using common sense Hermit crabs should rule the Earth but as we all know you're never more than 10ft away from a rat! Evolution is probably the explanation for these differences and the important facts that not all of a genome is actually used to build bodies and that sometimes chromosomes split (and join) for fairly random reasons like copying errors and viral infection etc. It is well documented that the explanation for Chimps having one more pair of chromosomes than Humans, even though we are so closely related, is that at some point in history something caused one pair of chromosomes to fuse. If you examine Human chromosome number 2 you can find the exact point this happened, which is an amazing discovery as well as an amazing piece of evidence for evolution itself.
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