Lobster

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Nephropidae
American lobster, Homarus americanus
American lobster, Homarus americanus
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Infraorder: Astacidea
Family: Nephropidae
Dana, 1852
Subfamilies and Genera

Clawed lobsters compose a family (Nephropidae, sometimes also Homaridae) of large marine crustaceans. Lobsters are economically important as seafood, forming the basis of a global industry that nets US$1.8 billion in trade annually.

Though several different groups of crustaceans are known as "lobsters," the clawed lobsters are most often associated with the name. Clawed lobsters are not closely related with spiny lobsters or slipper lobsters, which have no claws (chelae), or squat lobsters. The closest relatives of clawed lobsters are the reef lobster Enoplometopus and the three families of freshwater crayfish.

Biology

Lobsters are invertebrates and have a tough protective exoskeleton. Like most arthropods, lobsters must molt in order to grow, leaving them vulnerable during this time. During the molting process, several species may experience a change in color.

Lobsters live on rocky, sandy, or muddy bottoms from the shoreline to beyond the edge of the continental shelf. They generally live singly in crevices or in burrows under rocks.

Lobsters typically eat live food, consisting of fish, mollusks, other crustaceans, worms, and some plant life. Occasionally, they will scavenge if necessary, and may resort to cannibalism in captivity; however, this has not been observed in the wild. Lobster skin in the stomachs of lobsters has been found before, although this is because lobsters will eat their shed skin after molting [1]. Lobsters grow throughout their lives and it is not unusual for a lobster to live for more than 100 years [2]. They can thus reach impressive sizes. According to the Guinness World Records, the largest lobster was caught in Nova Scotia, Canada and weighed 20.14 kg (44.4 lb).

Being arthropods, lobsters are largely bilaterally symmetrical; clawed lobsters often possess unequal, specialized claws, like the king crab. A freshly caught lobster will have a claw that is full and fleshy, not atrophied. The anatomy of the lobster includes the cephalothorax which is the head fused with the thorax, both of which are covered by the carapace, of chitinous composition, and the abdomen. The lobster's head consists of antennae, antennules, mandibles, the first and second maxillae, and the first, second, and third maxillipeds. Because a lobster lives in a murky environment at the bottom of the ocean, its vision is poor and it mostly uses its antennae as sensors. Studies have shown that the lobster eye is formed with a reflective structure atop a convex retina. In contrast, most complex eyes use refractive ray concentrators (lenses) and a concave retina [3]. The abdomen of the lobster includes swimmerets and its tail is composed of uropods and the telson.

In general, lobsters move slowly by walking on the bottom of the sea floor. However, when they are in danger and need to flee, they swim backwards quickly by curling and uncurling their abdomen. A speed of 5 meters per second has been recorded [4].

Symbion

The genus Symbion, the only member of the phylum Cycliophora is only known from the gills of lobsters [5].

List of clawed lobster species

This list contains all known species in the family Nephropidae [6]:

Gastronomy

File:4 pound lobster.jpg
A 4–pound lobster ready to prepare

Lobster is a valued foodstuff; well-known recipes include Lobster Newberg and Lobster Thermidor. Lobster is best eaten fresh, and they are normally purchased live. Lobsters are usually shipped and sold with their claws banded to prevent them from injuring each other or the purchaser. Lobsters cannot open and close the claws when they are banded, which causes the claws to begin to atrophy inside the shell. Very fresh lobsters will not show this, and the claws will be full. Many restaurants that serve lobster keep a tank of the live creatures, often allowing patrons to pick their own.

If the lobster is to be boiled or steamed, most cooks place the live lobster into the pot. If the lobster is to be fried, grilled or baked it is best not to boil the lobster before further cooking. Freezing the lobster may toughen the meat.

When boiling a lobster, the general rule of thumb is to simmer the lobster for 7 minutes for the first pound and 3 minutes for each additional pound [7].

The shell of the lobster makes eating them a slow process for the unskilled or timid, who may require a number of implements including nutcrackers, a small fork, and a plastic bib. It is possible to shell a lobster by hand if one is careful to avoid the sharp points. The tail can be snapped open by first squeezing its sides inward, and then grabbing the edges of the shell, placing the thumbs on the dorsal side and pulling the sides apart. The claws usually open by hyper-extending the lobster's "thumb" and then pulling it out. Sometimes the claws can then be cracked by simply squeezing them. Otherwise, an ordinary fork is usually sufficient to snap open the side of the claw. Some restaurants will split the tail of the lobster and crack the claws in the kitchen. This is done to simplify their diner's meals and in some cases as a decorative step. (Especially when the lobster is to be served with a sauce poured over the tail.)

The majority of the meat is in the tail and the two front claws, but smaller quantities can be found in the legs and torso. The larger the lobster the greater the proportion of meat in the small legs and body. Lobster can be consumed simply, boiled or steamed, or used in a wide array of dishes and salads. It can be served as lobster soup or bisque or mixed with mayonnaise or salad dressing for lobster rolls. Lobster meat is often dipped in melted butter, resulting in a sweetened flavor.

History

The European wild lobster, among whom is the royal blue lobster of Audresselles, is more expensive and rare than the American lobster but was always appreciated chiefly among the royal and aristocratic families of France and the Netherlands. Such scenes were depicted in Dutch paintings of the sixteenth and seventeenth centuries.

In North America prior to the 20th century, local lobster was not a popular food. In the Maritimes, eating lobster was considered a mark of poverty. In some parts of the Maritime provinces of Canada, lobster was used as a fertilizer for farmers' fields, and a great deal of lobster was fed to slaves or the lower members of society. Outside of the rural outports lobster was sold canned, losing much of its flavour, which can be disguised if the lobster is dipped in drawn butter.

The reputation of lobster changed with the development of the modern transportation industry that allowed live lobsters to be shipped from the outports to large urban centres. Fresh lobster quickly became a luxury food and a tourist attraction for the Maritime provinces and Maine and an export to Europe and Japan where it is especially expensive.

The expense of eating lobster has led to supermarkets selling "faux lobster"; (which is clearly labeled as such), and it is made from fish (often pollock or other whitefish) that has been altered to look and taste similar to lobster. A few restaurants have gone so far as to sell "langostino lobster". Langostino translates into prawn, however the actual animal is, (more likely than not), a crab. Maine fishermen are upset that restaurants are passing off the fake as though is an actual lobster, (the spiny lobster is also called langouste). It is doubtful that the customers would be very happy to find out they are paying more for what is probably nothing more than a fancy-named crab. Rubio's Fresh Mexican Grill sold a "Lobster Burrito" which was made from squat lobster, another shellfish which is also very similar to the crab [8].

Catching

The usual method of catching lobsters has been to use baited, one-way traps located deep underwater with a coded marker buoy at the surface so that fishermen can find their cages and not pull up someone else's traps. Around the year 2000, due to overfishing and demand overwhelming supply, many countries began to try lobster farming, which is similar to fish farming.

Capacity for pain and suffering

The question of whether or not lobsters can experience pain is unresolved. Because of the ambiguous nature of suffering, most people who contend that lobsters do have this capacity approach the issue using 'argument by analogy' — that is, they hold that certain similarities between lobsters' and humans' biology or behavior warrants an assumption that lobsters can feel pain [9]. In February 2005, a review of the literature by the Norwegian Scientific Committee for Food Safety tentatively concluded that "it is unlikely that [lobsters] can feel pain," though they note that "there is apparently a paucity of exact knowledge on sentience in crustaceans, and more research is needed." This conclusion is based on the lobster's simple nervous system. The report assumes that the violent reaction of lobsters to boiling water is a reflex to noxious stimuli [10]. However, a Scottish review released in the same year reported that "scientific evidence ... strongly suggests that there is a potential for [lobsters] to experience pain and suffering," primarily because lobsters (and other decapod crustaceans) "have opioid receptors and respond to opioids (analgesics such as morphine) in a similar way to vertebrates," and because of similarities in lobsters' and vertebrates' stress systems and behavioral responses to pain [9].

Opioids

In vertebrates, endogenous opioids are neurochemicals that moderate pain by interacting with opiate receptors. Opioid peptides and opiate receptors occur naturally in crustaceans, and although "at present no certain conclusion can be drawn,"[10] some have interpreted their presence as an indication that lobsters may be able to experience pain [10][9]. The aforementioned Scottish paper holds that lobsters' opioids may "mediate pain in the same way" as in vertebrates [9].

Morphine, an analgesic, and naloxone, an opioid receptor antagonist, may affect a related species of crustacean (Chasmagnathus granulatus) in much the same way they affect vertebrates: injections of morphine into crabs produced a dose-dependent reduction of their defensive response to an electric shock [11]. (However, the attenuated defensive response could originate from either the analgesic or sedative properties of morphine, or both [12].) These findings have been replicated for other invertebrate species [12], but similar data is not yet available for lobsters.

Animal rights issues

The most common way of killing a lobster is by placing it, live, in boiling water. (This method is also used to kill crayfish and shrimp.) This is controversial because some people believe that the lobster suffers. The practice is illegal in some places, such as in Reggio Emilia, Italy, where offenders face fines of up to €495 [13]. The Norwegian study states that the lobster may be de-sensitized by placing it in a salt-solution 15 minutes before killing it. The quickest way to kill a lobster may be to insert a knife into its head and cleave the head in two, thereby destroying two of the most important nerve clusters of the lobster. Some feel that this is more humane than placing the live lobster into boiling water. Freezing the lobster for 15 minutes to 2 hours before boiling may de-sensitize the lobster.

Some stores will kill a lobster upon purchase by microwaving it. Whether or not death occurs more quickly than when the lobster is dropped in boiling water is not clear. There are, however, locations where the sale of a dead lobster to be eaten is illegal, including Massachusetts [14].

In 2006, British inventor Simon Buckhaven invented the CrustaStun, which electrocutes lobsters with a 110 V electric shock, killing them in about five seconds. This ensures a quicker death for the lobster. Seafood wholesalers in Britain already use a commercial version. A home version measuring about 46 cm width and depth came into the retail market in late 2006 for about GB£2000 [15][16].

Lobsters in culture

File:Mochelobster.jpg
Moche lobster, 200 A.D., Larco Museum Collection Lima, Peru

The Moche people of ancient Peru worshipped the sea and its animals. Lobsters were often depicted in their art [17].

References

  1. "Homarus americanus, Atlantic lobster". MarineBio.org. Retrieved 2006-12-27.
  2. David Foster Wallace (2005). Consider the Lobster and Other Essays. Little, Brown & Company. ISBN 0-31-615611-6.
  3. Land, M. F. (1976). "Superposition images are formed by reflection in the eyes of some oceanic decapod Crustacea". Nature. 263: 764–765. Unknown parameter |quotes= ignored (help)
  4. "The American lobster — frequently asked questions". St. Lawrence Observatory, Fisheries and Oceans Canada. 2005-10-19. Check date values in: |date= (help)
  5. M. Obst, P. Funch & G. Giribet (2005). "Hidden diversity and host specificity in cycliophorans: a phylogeographic analysis along my ta tas the North Atlantic and Mediterranean Sea". Molecular Ecology. 14: 4427–4440. doi:10.1111/j.1365-294X.2005.02752.x. Unknown parameter |quotes= ignored (help)
  6. Tshudy, D (2003). "Clawed lobster (Nephropidae) diversity through time". Journal of Crustacean Biology. 23: 178–186. Unknown parameter |quotes= ignored (help)
  7. "Cooking lobsters". Atwood Lobster Company. Retrieved 2007-06-30.
  8. Sarah Skidmore (2005-07-01). "The lobster in Rubio's burrito may be in hot water". The San Diego Union-Tribune. Check date values in: |date= (help)
  9. 9.0 9.1 9.2 9.3 Cephalopods and decapod crustaceans: their capacity to experience pain and suffering (PDF). Advocates for Animals. 2005.
  10. 10.0 10.1 10.2 L. Sømme (2005). "Sentience and pain in invertebrates: Report to Norwegian Scientific Committee for Food Safety". Norwegian University of Life Sciences, Oslo. Unknown parameter |quotes= ignored (help)
  11. M. Lozada, A. Romano & H. Maldonado (1988). "Effect of morphine and naloxone on a defensive response of the crab Chasmagnathus granulatus". Pharmacology Biochemistry and Behavior. 30 (3): 635–640. doi:10.1016/0091-3057(88)90076-7. Unknown parameter |quotes= ignored (help)
  12. 12.0 12.1 V. E. Dyakonova (2001). "Role of opioid peptides in behavior of invertebrates". Journal of Evolutionary Biochemistry and Physiology. 37: 335–347. Unknown parameter |quotes= ignored (help)
  13. Bruce Johnston (2004-03-06). "Italian animal rights law puts lobster off the menu". Daily Telegraph. Check date values in: |date= (help)
  14. "Chapter 94: Section 77G. Use of dead lobsters for food purposes; rapid freezing of live lobsters". Massachusetts General Court.
  15. "Lawyer invents lobster stun-gun". BBC News. 2006-06-18. Check date values in: |date= (help)
  16. Brendan I. Koerner (2006-06-25). "How a Lobster Leaves the Building". New York Times. Check date values in: |date= (help)
  17. Berrin, Katherine & Larco Museum. The Spirit of Ancient Peru:Treasures from the Museo Arqueológico Rafael Larco Herrera. New York: Thames and Hudson, 1997

External links

de:Hummerartige gd:Giomach id:Lobster la:Locusta marina ml:കൊഞ്ച് nl:Zeekreeften fi:Hummerit sv:Hummer ur:کَر کند


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