Although modern humans must now rely on dogs to sniff out drugs and other contraband at airports, our early ancestors may have been capable of the job themselves!
When we looked at gene expression, we found fairly small changes in 65 million years of the macaque, orangutan, and chimpanzee evolution.
The big question is why are humans so different. What sort of changes in the environment or lifestyle would drive such a rapid shift in the expression of genes - in this case in the liver- in humans and in no other primate?
The big question is why are humans so different?
It involves very little effort to create a huge effect.
No other animal relies on cooked food. Perhaps something in the cooking process altered the biochemical requirements for maximal access to nutrients as well as the need to process the natural toxins found in plant and animal foods.
