The all the inhabitants of earth suffered a wide spread epidemic known as narcisexualvapitism, a nocuous virus that loomed all over the world like a tarantula hugging a ping pong ball, was the cause of the extinction of the human-race. It's important to realize that it was not like Ebola, influenza, rotavirus, or an antenatal cult, but happen to be the act of taking a photo of your own beak.
Started sometime in the 21st century