The caridoid escape reaction, also known as lobstering or tail-flipping, refers to an innate escape mechanism in marine and freshwater crustaceans such as lobsters, krill, shrimp and crayfish. The reaction, most extensively researched in crayfish, allows crustaceans to escape predators through rapid abdominal flexions that produce powerful swimming strokes—thrusting the crustacean backwards through the water and away from danger. The type of response depends on the part of the crustacean stimulated, but this behavior is complex and is regulated both spatially and temporally through the interactions of several neurons. Discovery of the first command neuron-mediated behavior In 1946, C. A. G. Wiersma first described the tail-flip escape in the crayfish Procambarus clarkii and noted that the giant interneurons present in the tail were responsible for the reaction. The aforementioned neuronal fibres consist of a pair of lateral giant interneurons and a pair of medial giant interneurons, and Wiersma found that stimulating just one lateral giant interneuron (LG or LGI) or one medial giant interneuron (MG or MGI) would result in the execution of a tail flip. Wiersma and K. Ikeda then proposed the term "command neuron" in their 1964 publication, and applied it to the giant interneuron's ability to command the expression of the escape response. This was the first description of a command neuron-mediated behavior and it indicated that the depolarization of a neuron could precipitate complex innate behaviors in some organisms. This concept was further fleshed out with more specific and stringent conditions in 1972 when Kupfermann and Weiss published The Command Neuron Concept. The paper stated that command neurons were neurons (or small sets of neurons) carrying the entire command signal for a natural behavioral response. According to the authors, command neurons were both necessary and sufficient in the production of a behavioral response. The concept of command neuron-mediated behaviors was both ground breaking and controversial, since determining command neuron-mediated behaviors was a problematic process due to difficulties in understanding and interpreting anatomical and behavioral data. Research with crayfish Behavioral neurobiologists in the field of neuroethology have researched this behavior extensively for over fifty years in the crayfish species Procambarus clarkii. Based on studies of P. clarkii it was discovered that the tail- flip mechanism is characterized by a decisive, all-or-nothing quality that inhibits all unnecessary behaviors while generating a fixed action pattern for escape swimming. The type of escape response depends on the region of the