Humans have bred dogs for specific characteristics such as appearance, intelligence, herding instinct, and hunting instinct for well over 10,000 years. For the first time, scientists show that breeding not only changes the way the animals look, but also drives major changes in the dogs’ brains.

No other animal has been impacted by humans in the same way as dogs, and while it is well know that selective breeding from a small gene pool affects dogs’ physical health, for example through breed specific disorders, most haven’t considered just how much their bodies have adapted.

Researches from University of New South Wales and University of Sydney have found a dramatic reorganization in the brain of certain dog breeds. The brains in many short-snouted breeds have rotated forward as much as 15 degrees and relocated entire brain regions, for example the region controlling smell.

In pug-like breeds with a flat skull shape, the smell centre has drifted down to the lowest position in the skull. The next step will be to investigate just how much this impacts the dogs’ behavior.