In this potent 1 1/2 minute video, psychiatrist (and rabbi) Dr. Abraham Twerski shows a new view of stress, using lobsters as a perfect metaphor.(Video link here.)

We looked up how the lobster grows to make sure Rabbi Twerski had it right. It IS right, and the details are quite astonishing: when a lobster  leaves its shell in the process of growth (and change), it becomes very vulnerable (as do we)…

Because the shell of a lobster is hard and inelastic it must shed its shell in order to grow. Ecdysis, commonly called shedding, occurs when a lobster extrudes itself from its old shell. The overall process of preparing for, performing, and recovering from ecdysis is known as molting.  Unlike animals that are soft-bodied and have skin, a lobster’s shell, once hard, will not grow much more.  Lobsters show intermediate growth; that is, they grow throughout their lives and therefore spend much of that time preparing for, or undergoing ecdysis. 

Between molts a lobster’s flesh becomes densely packed within its shell, and a new shell, soft and flexible, is laid down inside the old.  Shortly before molting several things take place.  Calcium is moved from the old shell and deposited in special structures called gastroliths that are located on the stomach wall.  As blood leaves the appendages the flesh of the claws shrivels to about a quarter of their normal size to make it easier for them to be withdrawn.  Just prior to molting, a lobster absorbs lots of water, which causes the new shell to swell, eventually pushing away the old one.

During the molting process a lobster throws itself into a V-shape, lies on its side and begins to withdraw from its old shell.  The withdrawal begins when the large flexible membrane that joins the carapace and abdomen stretches and splits.  At the beginning of the molt the membranes holding the gastroliths break and the calcium is thrown into the stomach.  From there it is re-absorbed so that it may help in the immediate re-hardening of the new shell.  Escaping from its old shell may take the lobster anywhere from several minutes to a half hour, depending on environmental conditions and the size of the animal.  Once free of the old shell the lobster flips itself into its normal position.

Over the next few hours the lobster, who resembles a black rubber toy, will absorb water and will swell to reach its new size.  By gaining this sea water it may gain about 15% in size and 40-50% in weight.  The new shell has everything the old shell had, including all the same appendages, gills, mouthparts, antennae, antennules, eyestalks, and pleopods, as well as every hair, spine and bristle!  Amazingly a lobster even has the ability to regenerate lost appendages.  For example, a lobster may “throw” a claw to escape a dangerous situation, such as a fight with another lobster.  After its next molt the claw will begin to regenerate, and eventually a new claw will replace the lost one.

Molting takes place within the safety of the lobsters burrow.  Because of its new soft shell the lobster is easy prey and must remain in hiding for at least a week or two.  A newly molted lobster will begin to eat its old shell and other material high in calcium in order to strengthen its new shell.  During the months that a lobster shell takes to fully harden, tissue replaces the water that was gained prior to molting.  In effect, the lobster fully grows into its shell and the cycle of molting and growing begins again.

 Many factors control when a lobster will molt; water temperature, food supply, salinity, type of bottom, depth of water and availability of shelter are some examples.  Although lobsters molt quite frequently at first, five or six times in the first season, as they grow the length of time between molts increases.  An adult lobster will molt only once or twice a year...  — The American Lobster

Lobster image via Vintage Printable

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