AO3

• Tinbergen (1951) an experiment with male sticklebacks. This species of fish is very territorial and aggressive. In the mating season they develop a red spot on their underside. Tinbergen observed that at this time male sticklebacks will attack another male stickleback that enters their territory. He theorised that the red spot on their underside was acting as an innate releasing mechanism and when one stickleback observed another stickleback with this red spot they would initiate the aggressive attack behaviour which is an example of a fixed action pattern.
• Tinbergen (1951) an experiment with male sticklebacks. This species of fish is very territorial and aggressive.

  • To test this out he presented male sticklebacks with a wooden model; if the wooden model had a red spot, then the male stickleback would attack. However, without the red spot the male stickleback would not react, and there was no aggression displayed. The fact that animals such as sticklebacks can demonstrate complex aggressive behaviour due to primarily nature-based factors supports the idea that genetic information plays a role in expressed aggressive behaviour.
• There is evidence from the animal kingdom that aggression is not always ritualistic, Goodall (2010) studied chimpanzee behaviour for over 50yrs. She observed groups of chimpanzees that waged a brutal war against neighbouring groups of chimpanzees, slaughtering all members of the group. Goodall (2010) referred to this type of gang behaviour as the systematic slaughtering of one group by another stronger group. This aggression is hard to explain from an ethological standpoint as the risk of injury to the attacking group is high and thus does not appear to be an adaptive behaviour.