Angry Birds becomes a lot less fun when that bird is in real life, and it's dive-bombing your head. This aggressive blackbird was caught on camera unleashing volleys of sky-terror on unsuspecting passers-by in San Francisco’s Golden Gate Park. The reactions are priceless: people shriek. People get mad. A little boy cries. Universally the look on their faces is "What the hell was that?!"
But why was this blackbird so angry? It could all be in her head. In 2012 researchers reported that levels of a brain chemical, called VIP, could predict how aggressive certain species of birds were. VIP is secreted in the hypothalamus, a region of the brain that controls basic functions like hunger, sleep and aggression. By using a small piece of DNA that specifically matched to waxbills' — notoriously aggressive birds — brand of VIP, scientists created an injection that stopped the birds' neurons from producing the anger-inducing chemical. The waxbills' reactions to intruders went from instant brawling to more sedate warning chirps. In birds that were less aggressive, like zebra finches, the injection made them even more peaceable. Perhaps this bird has got sky-high VIP levels — or perhaps there's another explanation. You'll have to watch to the end to find out.