We don’t know why this happened, but Kulathinal has an interesting theory.

“In research labs you have to transfer your flies into a different container every two weeks. When you flip the flies, the fast ones escape and the dumb ones remain. So over generations you end up selecting for slow, dumb-witted flies as opposed to faster ones that can escape.”

So what unites the dog, chicken, fox, mouse and fly? Whether they have chosen to or not, each have become inextricably linked with people. In sharing our lives and scavenging our leftovers, each of these species has had to overcome a fear of humans to survive.

“When you start thinking about the initial phases of domestication going back thousands of years, the absolute first step must have been a reduced fear of humans, as fearful animals can’t thrive and reproduce,” explains Per Jenson.

What our hunter gatherer ancestors couldn’t have known, is that a host of other changes would piggyback on the ‘tameness’ ride for free.

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