Also known as warning colouration, this refers to how animals change colour or adapt physically to counter threats from various predators. Such features warn predators to refrain from attacking an animal as it is either poisonous or possesses other self-defence mechanisms to harm the predator. In contrast to other protective mechanisms, which usually try to hide the creature from potential predators, aposematic warning mechanisms try to grab the attention of predators by advertising their dangerous characteristics. The idea was first proposed in 1866 by British biologist Alfred Russell Wallace.
