Starfish by the starfish in an escape response. The loss of parts of the body is achieved by the rapid softening of a special type of connective tissue in response to nervous signals. This type of tissue is called catch connective tissue and is found in most echinoderms. An autotomy-promoting factor has been identified which, when injected into another starfish, causes rapid shedding of arms. The lifespan of a starfish varies considerably between species, generally being longer in larger forms and in those with planktonic larvae. For example, "Leptasterias hexactis" broods a small number of large-yolked eggs. It has an adult
Spiny lobster lobster's antennae against a "file". The noise is produced by frictional vibrations - sticking and slipping, similar to rubber materials sliding against hard surfaces. While a number of insects use frictional vibration mechanisms to generate sound, this particular acoustic mechanism is unique in the animal kingdom. Significantly, the system does not rely on the hardness of the exoskeleton, as many other arthropod sounds do, meaning that the spiny lobsters can continue to produce the deterrent noises even in the period following a moult when they are most vulnerable. The stridulating organ is present in all but three genera in the