The jararaca is a venomous pit viper commonly found in South America. Its venom packs a deadly mix of toxins that causes excruciating pain, life-threatening bleeding, and kidney failure. What makes this snake particularly scary even among vipers is its particularly aggressive nature. This snake will bite first and ask questions later whenever it considers itself threatened. So, what is the threshold that triggers the jararaca’s defensive behavior? Or maybe an even better question is why some snakes bite while others are chill. Biologist João Miguel Alves-Nunes reasoned there’s only one way to …