Path followed:
- Is the fault in the components that perform any physical action?
Answer: Yes
- Is the fault in components that move?
Answer: Yes
- Is the fault in components that make the mechanism move?
Answer: Yes
- Is the faulty component designed to move the mechanism around?
Answer: Yes
- Is the faulty component needed for stability?
Answer: No
- Does the faulty component manipulate smaller objects?
Answer: Yes
- Is the faulty component rigid?
Answer: Yes
- Are there any external resources that can be used by the mechanism?
Answer: No
- Do the dimensions of the replaced component change after regeneration?
Answer: Yes
2) Snapping Shrimp or Pistol Shrimp, Alpheus heterochelis
The Snapping Shrimp can be found along the United States Atlantic Coast and in the Gulf of Mexico. It is characteristically seen with one large claw and another smaller pincer. It has the capability of growing out the smaller pincer if the big claw is detached and growing a smaller pincer in its place.
The Snapping Shrimp can detach its larger claw when in a fight or can get it amputated. The shrimp undergoes a molting process several times throughout its life to grow in size and to regrow its claws. The process includes 4 stages: postecdysis, intermoult, proecdysis, and ecdysis (“Moulting”). During the postecdysis stage the old exoskeleton has been shed and the new exoskeleton expands due to increased hemolymph volume from water influx (“Moulting”) and later the exoskeleton hardens from calcium deposition. During the intermoult stage the water in the skeleton is used to create tissues, which cause the shrimp to become larger in size. This allows the smaller pincer to grow into the larger pincer, if need be. The stage also allows primary cell division and differentiation that results in the formation of basal papillae (Mykles). The proecdysis stage happens just before molting and allows for the calcium to be reabsorbed into the epidermal cells. During this stage the limb can grow and form the smaller pincer, although it takes 3 or more molting stages to become a mature claw (Ariane et al.). This stage can also develop the smaller pincer into the larger claw if it was amputated. The ecdysis stage begins with the old exoskeleton opening and ends when the crustacean escapes.
“Moulting.” Moulting. Laboratory of Aquaculture & Artemia Reference Center, 2007. Web. 05 Nov. 2014.
http://www.aquaculture.ugent.be/Education/coursematerial/online%20courses/shrimp-cd/bio/moultb.htm
Ariane Pereira, Erica Tracey, Patricia C. Cooney, Christopher A. Korey, Melissa Hughes. Post-autotomy claw regrowth and functional recovery in the snapping shrimp Alpheus angulosus. Marine and Freshwater Behaviour and Physiology,
Vol. 47, Iss. 3, 2014. Taylor & Francis Online. Web. 05 Nov. 2014.
http://www.tandfonline.com/doi/full/10.1080/10236244.2014.928460#preview
Mykles, Donald L. “Interactions Between Limb Regeneration and Molting in Decapod Crustaceans1.” American Zoologist 41.3 (2001): 399-406.Integrative & Comparative Biology. Web. 5 Nov. 2014.