My favorite research organism is the crayfish. This animal has a wide range of interesting behaviors, and their aggressive interactions are far more entertaining than anything seen on nature shows. Crayfish, and generally most crustaceans, seem to always be in a fighting mood. So, they are excellent models to study social and fighting behaviors. The reason I chose to start working on crayfish was the immense role that chemical signals play in crayfish behavior. These animals use chemicals to make just about every decision that an animal needs to make. Hunting, fighting, and avoiding predators all depend on a suite of chemicals put forward either by themselves, their opponents, predators, or prey. Mating and finding shelter are also heavily guided and influenced by subtle chemicals in the lakes and streams in which crayfish are found.