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| Lamprey
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The mouth of a Sea Lamprey, showing teeth and tongue | ||||||||||
| Scientific classification | ||||||||||
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Geotriinae Mordaciinae Petromyzontinae
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A lamprey is a type of fish with a toothed, funnel-like, jawless sucking mouth with which it bores into the flesh of other fishes to suck their blood. In Zoology, Lampreys are not reckoned to be true fish because of the vastly different build of their body.
Lampreys live mostly in coastal and freshwaters, although at least one species, Geotria australis probably travels significant distances in the open ocean, as is evidenced by the lack of reproductive isolation between Australian and New Zealand populations, and the capture a specimen in the Southern Ocean between Australia and Antartica. They are found in most temperate regions except Africa. Their larvae have a low tolerance for high water temperatures, which is probably the reason that they are not found in the tropics. Outwardly resembling eels in that they have no scales, an adult lamprey can range anywhere from 5 to 40 inches (13 to 100 centimetres) long. Lampreys have one or two dorsal fins, large eyes, one nostril on the top of their head, and seven gills on each side. A lamprey has cartilage instead of bones and is on the borderline between vertebrates and invertebrates.
Lampreys begin life as burrowing, freshwater larvae (ammocoetes). At this stage, they are toothless, have rudimentary eyes, and feed on microorganisms. This larval stage can last five to seven years, and hence, was originally thought to be an independent organismIn biology and ecology, an organism is a living being. The origin of life and the relationships between its major lineages are controversial. Two main grades may be distinguished, the prokaryotes and eukaryotes. The prokaryotes are generally considered to. After these five to seven years, they transform into adults in a metamorphosis which is at least as radical as that seen in amphibians, and which involves a radical rearangement of internal organs, development of eyes and transformation from a mud-dwelling filter feeder into an efficient swimming predator, which typically moves into the sea to begin a predatory/ parasiticA parasite is an organism that lives in or on the living tissue of a host organism at the expense of it. The biological interaction between the host and the parasite is called parasitism. Parasitism is a type of symbiosis, by one definition, although anot life, attaching to a fish by their mouths and feeding on the blood and tissues of the host. Whether lampreys are predators or parasites is a blurred question.
To reproduce, lampreys return to freshwater, build a nest, then spawn, that is, lay their eggs, and die. In Geotria australis, the time between ceasing to feed at sea and spawning can be up to 18 months long - surely one of the most remarkable endurance events in the animal kingdom. Not all lampreys can be found in the sea. Some lampreys are landlocked and remain in freshwater, and some of these stop feeding altogether as soon as they have left the larval stage.
Lampreys have long been used as foodFood is any substance normally eaten or drunk by living organisms. The term food also includes liquid drinks. Food is the main source of energy and of nutrition for animals, and is usually of animal or plant origin. The study of food is called food scienc for humans.
Recent studies reported in NatureNature is one of the oldest and most reputable general-purpose scientific journals, first published on November 4, 1869. Although most scientific journals are now highly specialized, Nature still publishes articles across a wide range of scientific fields suggest that lampreys have evolved a unique type of immune systemThe immune system is any system present in an organism to prevent predation by biological agents. All living organisms have these protective measures, although they vary radically in scope and mechanism. In humans and domesticated animals, the immune syst with parts that are unrelated to the antibodies found in mammalSubclass Monotremata Monotremata Subclass Marsupialia Didelphimorphia Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemorphia Diprotodontia Subclass Placentalia Xenarthra Dermoptera Desmostylia Scandentia Primates Rodentia Lagomorps.
They also have a very high tolerance to iron overload, and have evolved biochemical defenses to detoxify this metal.
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