Scallop

Scallop
Scallop
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Bivalvia
Order: Ostreoida
Suborder: Pectinina
Superfamily: Pectinoidea
Family: Pectinidae
Rafinesque, 1815
Genera

See Pectinidae

A scallop (play /ˈskɒləp/ or /ˈskæləp/) is a marine bivalve mollusk of the family Pectinidae. Scallops are a cosmopolitan family, found in all of the world's oceans. Many scallops are highly prized as a food source. The brightly colored, fan-shaped shells of some scallops, with their radiating fluted pattern, are valued by shell collectors.

The name "scallop" is derived from the Old French escalope, which means "shell".[1]

Contents

Anatomy

Scallops have up to 100 simple eyes

Like the true oysters (family Ostreidae), scallops have a central adductor muscle, and thus the inside of their shells has a characteristic central scar, marking the point of attachment for this muscle. The adductor muscle of scallops is larger and more developed than that of oysters, because they are active swimmers; scallops are in fact the only migratory bivalve. Their shell shape tends to be highly regular, recalling one archetypal form of a seashell, and because of this pleasing geometric shape, the scallop shell is a common decorative motif.

Scallops have up to 100 simple eyes strung around the edges of their mantles like a string of beads. They are reflector eyes, about one mm in diameter, with a retina that is more complex than those of other bivalves. Their eyes contain two retina types, one responding to light and the other to abrupt darkness, such as the shadow of a nearby predator. They cannot resolve shapes, but can detect changing patterns of light and motion.[2][3]

Reflector eyes are an alternative to a lens where the inside of the eye is lined with mirrors which reflect the image to focus at a central point.[4] The nature of these eyes means that if one were to peer into the pupil of an eye, one would see the same image that the organism would see, reflected back out.[4] The scallop Pecten has up to 100 millimeter-scale reflector eyes fringing the edge of its shell. It detects moving objects as they pass successive lenses.[4]

Food and digestion

Most scallops are filter feeders, and eat plankton. Coincidentally, the plankton can include scallop larvae. Siphons bring water over a filtering structure, where food becomes trapped in mucus. Next, the cilia on the structure move the food toward the mouth. Then, the food is digested in the stomach and digestive gland. Waste is passed on through the intestine and exits via the anus.

Life habits

Most scallops are free-living, but some species can attach to a substrate by a structure called a byssus, or even be cemented to their substrate as adults (e.g. Hinnites spp.). Other scallops can extend a "foot" from between their valves (shell). By then contracting the foot, they can burrow themselves deeper into sand. A free-living scallop can swim by rapidly opening and closing its shell. This method of locomotion is also a defensive technique, protecting it from threatening predators. So-called Singing Scallops can make an audible soft popping sound as they flap their shells underwater.

Reproductive cycle

The scallop family is unusual in that some members of the family are dioecious (males and females are separate), while other are simultaneous hermaphrodites (both sexes in the same individual) and a few are protoandrous hermaphrodites (males when young then switching to female). Red roe is that of a female, and white, that of a male. Spermatozoa and ova are released freely into the water during mating season and fertilized ova sink to the bottom. After several weeks, the immature scallop hatches and the larvae drift in the plankton until settling to the bottom again to grow, usually attaching by means of byssal threads. Some scallops, such as the Atlantic bay scallop Argopecten irradians are short lived, while others can live 20 years or more. Age can often be inferred from annuli, the concentric rings of their shells.

Seafood industry

Scallop and pecten catch in 2005

Wild fisheries

By far the largest wild scallop fishery is for the Atlantic sea scallop (Placopecten magellanicus) found off northeastern United States and eastern Canada. Most of the rest of the world's production of scallops is from Japan (wild, enhanced, and aquaculture), and China (mostly cultured Atlantic bay scallops).

Scallops are most commonly harvested using scallop dredges or bottom trawls. Recently, scallops harvested by divers, hand-caught on the ocean floor, have entered the marketplace. In contrast to scallops captured by a dredge across the sea floor, diver scallops tend to be less gritty. They may also be more ecologically friendly, as the harvesting method does not cause damage to undersea flora or fauna. In addition, dredge-harvesting methods often result in delays of up to two weeks before the scallops arrive at market, which can cause the flesh to break down, and results in a much shorter shelf life.

Aquaculture

In 2005, China accounted for 80 percent of the global scallop and pecten catch, according to an FAO study.[5] Within Europe, Russia remained the industry leader.

Sustainability

New Zealand

The Tasman Bay area has been closed to commercial scallop harvesting for the past two years due to a decline in the numbers. Industry-funded research is currently being conducted into scallop harvesting patterns. Forest and Bird list scallops as "Worst Choice" in their Best Fish Guide for sustainable seafood species.[6]

United States

On the east coast of the United States, over the last 100 years, the populations of bay scallops have greatly diminished. This decrease is due to several factors, but probably is mostly due to reduction in sea grasses (to which bay scallop spat attach) due to increased coastal development and concomitant nutrient runoff. Another possible factor is reduction of sharks from overfishing. A variety of sharks used to feed on rays, which are a main predator of bay scallops. With the shark population reduced—in some places almost eliminated—the rays have been free to dine on scallops to the point of greatly decreasing their numbers. By contrast, the Atlantic sea scallop (Placopecten magellanicus) is at historically high levels of abundance after recovery from overfishing.

As food

Scallops are a popular type of shellfish in both Eastern and Western cooking. They are characterized by having two types of meat in one shell: the adductor muscle, called "scallop" which is white and meaty, and the roe, called "coral", which is red or white and soft.

In Western cuisine, scallops are commonly sautéed in butter, or else breaded and deep fried. When a scallop is prepared, the byssus, also called the beard,[7] which tends to be tough, is usually discarded or used later on for stock.[8] Sometimes, markets sell scallops already prepared in the shell, with only the adductor muscle intact. Outside the U.S. the scallop is often sold whole.

Scallops that are without any additives are called "dry packed", while scallops that are treated with sodium tripolyphosphate (STPP) are called "wet packed". STPP causes the scallops to absorb moisture prior to the freezing process, thereby getting a better price per unit of weight. The freezing process takes about two days.

In Japanese cuisine, scallops may be served in soup or prepared as sashimi or sushi. Dried scallop is known in Cantonese Chinese cuisine as conpoy (乾瑤柱, 乾貝, 干貝).

In a sushi bar, hotategai (帆立貝, 海扇) is the traditional scallop on rice, and while kaibashira (貝柱) may be called scallops, it is actually the adductor muscle of any kind of shellfish, e.g. mussels, oysters, or clams.

Scallops have lent their name to the culinary term scalloped, which originally referred to seafood creamed and served hot in the shell (Rombauer 1964). Today it means a creamed casserole dish such as scalloped potatoes, which contains no seafood at all.

Symbolism

Portrait by Carlo Crivelli, c. 1480

Shell of Saint James

The scallop shell is the traditional emblem of James, son of Zebedee and is popular with pilgrims on the Way of St James to the apostle's shrine at Santiago de Compostela in Spain. Medieval Christians making the pilgrimage to his shrine often wore a scallop shell symbol on their hat or clothes. The pilgrim also carried a scallop shell with him, and would present himself at churches, castles, abbeys etc., where he could expect to be given as much sustenance as he could pick up with one scoop. Probably he would be given oats, barley, and perhaps beer or wine. Thus even the poorest household could give charity without being overburdened. The association of Saint James with the scallop can most likely be traced to the legend that the apostle once rescued a knight covered in scallops. An alternative version of the legend holds that while St. James' remains were being transported to Spain from Jerusalem, the horse of a knight fell into the water, and emerged covered in the shells.[citation needed]

Fertility symbol

Aphrodite in a sea shell, from Amisos, now in the Louvre

Throughout antiquity, scallops and other hinged shells have symbolized the feminine principle.[9] Outwardly the shell can symbolize the protective and nurturing principle, and inwardly the "life-force slumbering within the Earth",[10] an emblem of the vulva.[11][12]

Many paintings of Venus, the Roman goddess of love and fertility, included a scallop shell in the painting to identify her. This is evident in Botticelli's classically inspired The Birth of Venus (also known as Venus on the half-shell[13]).

One legend of the Way of St. James holds that the route was seen as a sort of fertility pilgrimage, undertaken when a young couple desired to bear offspring. The scallop shell is believed to have originally been carried therefore by pagans as a symbol of fertility.[14][15]

Alternatively, the scallop resembles the setting sun, which was the focus of the pre-Christian Celtic rituals of the area. To wit, the pre-Christian roots of the Way of St. James was a Celtic death journey westwards towards the setting sun, terminating at the End of the World (Finisterra) on the "Coast of Death" (Costa da Morte) and the "Sea of Darkness" (i.e., the Abyss of Death, the Mare Tenebrosum, Latin for the Atlantic Ocean, itself named after the Dying Civilization of Atlantis).[16] The reference to St. James rescuing a "knight covered in scallops" is therefore a reference to St. James healing, or resurrecting, a dying (setting sun) knight. Similarly, the notion of the "Sea of Darkness" (Atlantic Ocean) disgorging St. James' body, so that his relics are (allegedly) buried at Santiago de Compostella on the coast, is itself a metaphor for "rising up out of Death", that is, resurrection.[17]

Heraldry

A scallop shell as a heraldic device on a German coat of arms

The scallop shell symbol found its way into heraldry as a badge of those who had been on the pilgrimage to Compostela, although later it became a symbol of pilgrimage in general. Winston Churchill's family coat of arms includes a scallop; another example is the surname Wilmot and also John Wesley's (which as a result the scallop shell is used as an emblem of Methodism). However, charges in heraldry do not always have an unvarying symbolic meaning, and there are cases of arms in which no family member went on a pilgrimage and the occurrence of the scallop is simply a pun on the name of the armiger, or for other reasons.

State shell of New York

The U.S. state of New York made the Atlantic bay scallop its state shell in 1988.

In design

In design, scalloped edges or ridges refers to a wavy pattern reminiscent of the edge of a scallop's shell.

References

  1. ^ www.etymonline.com Note: earlier versions of this article claim the word "scallop" originated from the ancient Canaanite sea port Ascalon (modern city of Ashkelon, Israel). This error is probably due to the close proximity of the words "scallion" and "scallop" in many dictionaries. The word "scallion" has origins in Ascalon (see the same link cited at the beginning of this reference). Unfortunately, as of August 2009, Google search results for "ascalon scallop" indicate over 3300 pages now cite the incorrect information from the earlier version of this article.
  2. ^ http://www.asknature.org/strategy/1e779a45a88aef5c45448073f1e77216
  3. ^ Land MF and Fernald RD (1992) "The evolution of eyes" Annual review of neuroscience, 15: 1–29.
  4. ^ a b c Land, M F; Fernald, R D (1992). "The Evolution of Eyes". Annual Review of Neuroscience 15: 1–29. doi:10.1146/annurev.ne.15.030192.000245. PMID 1575438. 
  5. ^ China catches 1m tonnes of scallops and pectens in 2005
  6. ^ http://www.forestandbird.org.nz/what-we-do/publications/-best-fish-guide-/scallops
  7. ^ http://www.epicurious.com/tools/fooddictionary/search?query=beard
  8. ^ Larousse Gastronomique, Clarkson Potter/Publishers, 2001, p. 1062
  9. ^ Salisbury JE (2001) Women in the ancient world, p. 11. ABC-CLIO, ISBN 9781576070925.
  10. ^ Fontana D (1994) The secret language of symbols: a visual key to symbols and their meanings, pp. 88, 103. Chronicle Books, ISBN 9780811804622.
  11. ^ Gutzwiller K (1992) "The Nautilus, the Halycon, and Selenaia: Callimachus's Epigram 5 Pf.= 14 G.-P.", Classical Antiquity, 11(2): 175-193.
  12. ^ Johnson B (1994) Lady of the beasts: the Goddess and her sacred animals, p. 230. Inner Traditions/Bear & Company, ISBN 9780892815234.
  13. ^ Porter D and Prince D (2009) Frommer's Italy 2010, p. 273. Frommer's, ISBN 9780470470695.
  14. ^ Slavin S (2003) "Walking as Spiritual Practice: The Pilgrimage to Santiago de Compostela" Body and Society 9(1):18. doi 10.1177/1357034X030093001
  15. ^ Gauding M (2009) The Signs and Symbols Bible: The Definitive Guide to Mysterious Markings, Page 169. Sterling Publishing Company. ISBN 9781402770043
  16. ^ Thomas, Isabella. "Pilgrim's Progress". Europe in the UK. European Commission.
  17. ^ Pinkham MA (2004) Guardians Of The Holy Grail: The Knights Templar, John The Baptist, And The Water Of Life Page 235. Adventures Unlimited Press. ISBN 9781931882286
  • Barucca M, Olmo E, Schiaparelli S, Canapa A (2004) Molecular phylogeny of the family Pectinidae (Mollusca: Bivalvia)
  • Rombauer, Irma S. and Marion Rombauer Becker (1931 [1964]) The Joy of Cooking, p 369. Indianapolis: Bobbs-Merrill. ISBN 0-452-25665-8.

External links


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Synonyms:

Look at other dictionaries:

  • Scallop — Scal lop (?; 277), n. [OF. escalope a shell, probably of German or Dutch origin, and akin to E. scale of a fish; cf. D. schelp shell. See {Scale} of a fish, and cf. {Escalop}.] [Written also {scollop}.] 1. (Zo[ o]l.) Any one of numerous species… …   The Collaborative International Dictionary of English

  • Scallop — Scal lop, v. t. [imp. & p. p. {Scalloped}; p. pr. & vb. n. {Scalloping}.] 1. To mark or cut the edge or border of into segments of circles, like the edge or surface of a scallop shell. See {Scallop}, n., 2. [1913 Webster] 2. (Cookery) To bake in… …   The Collaborative International Dictionary of English

  • scallop — (n.) bivalve mollusk, c.1400, from O.Fr. escalope shell, variant of eschalope, probably from a Germanic source (Cf. O.N. skalpr sheath, M.Du. schelpe shell ); see SCALE (Cf. scale) (n.1). Extended 17c. to objects shaped like scallop shells,… …   Etymology dictionary

  • scallop — pronounced skol ǝp, is the preferred spelling for the name of the mollusc, not scollop. The verb (meaning e.g. ‘to decorate with scallop designs’) has inflected forms scalloped, scalloping …   Modern English usage

  • scallop — ► NOUN 1) an edible bivalve mollusc with a ribbed fan shaped shell. 2) each of a series of small curves resembling the edge of a scallop shell, forming a decorative edging. ► VERB (scalloped, scalloping) 1) (scalloped) decorated with scallops. 2) …   English terms dictionary

  • scallop — [skäl′əp, skal′əp] n. [ME scalop < OFr escalope < escale: see SCALE2] 1. any of a family (Pectinidae) of bivalves with two deeply grooved, convex shells and an earlike wing on each side of the hinge, that swims by rapidly snapping its… …   English World dictionary

  • scallop — /skol euhp, skal /, n. 1. any of the bivalve mollusks of the genus Argopecten (Pecten) and related genera that swim by rapidly clapping the fluted shell valves together. 2. the adductor muscle of certain species of such mollusks, used as food. 3 …   Universalium

  • scallop — n. & v. (also scollop) 1 any of various bivalve molluscs of the family Pectinidae, esp. of the genus Chlamys or Pecten, much prized as food. 2 (in full scallop shell) a a single valve from the shell of a scallop, with grooves and ridges radiating …   Useful english dictionary

  • scallop — I. noun also scollop Etymology: Middle English scalop, from Anglo French escalope shell, of Germanic origin; akin to Middle Dutch schelpe shell Date: 15th century 1. a. any of numerous marine bivalve lamellibranch mollusks (family Pectinidae)… …   New Collegiate Dictionary

  • scallop — UK [ˈskɒləp] / UK [ˈskæləp] / US / US [ˈskɑləp] noun Word forms scallop : singular scallop plural scallops 1) a) [countable] a shellfish with two shells that fit together b) [uncountable] a scallop eaten as food 2) [countable, usually plural] one …   English dictionary

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