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Rhesus monkey

The first primate to get rocketed into space and to be cloned, the rhesus monkey, had its genome sequenced in 2007. The rhesus monkey genome has about 93 percent similarity with that of humans, which is important since it is often used in medical testing for human drugs and therapies.

The researchers identified roughly 200 genes that appear to be key players in what defines the differences between our species. These include genes involved in hair formation, sperm-egg fusion, immune response and changes to cell membrane proteins.

The rhesus monkey shows the same mysterious rearrangements that are seen in the human lineage's X chromosome following the branching off of the chimpanzee which gives us new evidence of the unusual role of this sex chromosome in primate evolution.