HOME
        TheInfoList






  Sea urchin injuries are puncture wounds inflicted by the animal's brittle, fragile spines.[52] These are a common source of injury to ocean swimmers, especially along coastal surfaces where coral with stationary sea urchins are present. Their stings vary in severity depending on the species. Their spines can be venomous or cause infection. Granuloma and staining of the skin from the natural dye inside the sea urchin can also occur. Breathing problems may indicate a serious reaction to toxins in the sea urchin.[53] They inflict a painful wound when they penetrate human skin, but are not themselves dangerous if fully removed promptly; if left in the skin, further problems may occur.[54]

Science

Sea urchins are traditional model organisms in developmental biology. This use originated in the 1800s, when their embryonic development became easily viewed by microscopy. The transparency of the urchin's eggs enabled them to be used to observe that sperm cells actually fertilize ova.[55] They continue to be used for embryonic studies, as prenatal development continues to seek testing for fatal diseases. Sea urchins are being used in longevity studies for comparison between the young and old of the species, particularly for their ability to regenerate tissue as needed.[56] Scientists at the University of St Andrews have discovered a genetic sequence, the '2A' region, in sea urchins previously thought to have belonged only to viruses that afflict humans like foot-and-mouth disease virus.[57] More recently, Eric H. Davidson and Roy John Britten argued for the use of urchins as a model organism due to their easy availability, high fecundity, and long lifespan. Beyond embryology, urchins provide an opportunity to research cis-regulatory elements.[58] Oceanography has taken an interest in monitoring the health of urchins and their populations as a way to assess overall ocean acidification,[59] temperatures, and ecological impacts.

The organism's evolutionary placement and unique embryology with five-fold symmetry were the major arguments

Sea urchins are traditional model organisms in developmental biology. This use originated in the 1800s, when their embryonic development became easily viewed by microscopy. The transparency of the urchin's eggs enabled them to be used to observe that sperm cells actually fertilize ova.[55] They continue to be used for embryonic studies, as prenatal development continues to seek testing for fatal diseases. Sea urchins are being used in longevity studies for comparison between the young and old of the species, particularly for their ability to regenerate tissue as needed.[56] Scientists at the University of St Andrews have discovered a genetic sequence, the '2A' region, in sea urchins previously thought to have belonged only to viruses that afflict humans like foot-and-mouth disease virus.[57] More recently, Eric H. Davidson and Roy John Britten argued for the use of urchins as a model organism due to their easy availability, high fecundity, and long lifespan. Beyond embryology, urchins provide an opportunity to research cis-regulatory elements.[58] Oceanography has taken an interest in monitoring the health of urchins and their populations as a way to assess overall ocean acidification,[59] temperatures, and ecological impacts.

The organism's evolutionary placement and unique embryology with five-fold symmetry were the major arguments in the proposal to seek the sequencing of its genome. Importantly, urchins act as the closest living relative to chordates and thus are of intere

The organism's evolutionary placement and unique embryology with five-fold symmetry were the major arguments in the proposal to seek the sequencing of its genome. Importantly, urchins act as the closest living relative to chordates and thus are of interest for the light they can shed on the evolution of vertebrates.[60] The genome of Strongylocentrotus purpuratus, was completed in 2006 and established homology between sea urchin and vertebrate immune system-related genes. Sea urchins code for at least 222 Toll-like receptor genes and over 200 genes related to the Nod-like-receptor family found in vertebrates.[61] This increases its usefulness as a valuable model organism for studying the evolution of innate immunity. The sequencing also revealed that while some genes were thought to be limited to vertebrates, there were also innovations that have previously never been seen outside the chordate classification, such as immune transcription factors PU.1 and SPIB.[60]

The gonads of both male and female sea urchins, usually called sea urchin roe or corals,[62] are culinary delicacies in many parts of the world.[63][64][65] In Mediterranean cuisines, Paracentrotus lividus is often eaten raw, or with lemon,[66] and known as ricci on Italian menus where it is sometimes used in pasta sauces. It can also flavour omelettes, scrambled eggs, fish soup,[67] mayonnaise, béchamel sauce for tartlets,[68] the boullie for a soufflé,[69] or Hollandaise sauce to make a fish sauce.[70] In Chilean cuisine, it is served raw with lemon, onions, and olive oil. Though the edible Strongylocentrotus droebachiensis is found in the North Atlantic, it is not widely eaten. However, sea urchins (called uutuk in Alutiiq) are commonly eaten by the Alaska Native population around Kodiak Island. It is commonly exported, mostly to Japan.[71] In the West Indies, slate pencil urchins are eaten.[63] On the Pacific Coast of North America, Strongylocentrotus franciscanus was praised by Euell Gibbons; Strongylocentrotus purpuratus is also eaten.[63] In New Zealand, Evechinus chloroticus, known as kina in Maori, is a delicacy, traditionally eaten raw. Though New Zealand fishermen would like to export them to Japan, their quality is too variable.[72] In Japan, sea urchin is known as uni (うに), and its roe can retail for as much as ¥40,000 ($360) per kg;[73] it is served raw as sashimi or in sushi, with soy sauce and wasabi. Japan imports large quantities from the United States, South Korea, and other producers. Japan consumes 50,000 tons annually, amounting to over 80% of global production.[74] Japanese demand for sea urchins has raised concerns about overfishing.[75] Native Americans in California are also known to eat sea urchins.[76] The coast of Southern California is known as a source of high quality uni, with divers picking sea urchin from kelp beds in depths as deep as 24 m/80 ft.[77] As of 2013, the state was limiting the practice to 300 sea urchin diver licenses.[77]