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The Vampire Squid (Vampyroteuthis infernalis, lit. Carl Chun ( October 1, 1852 – April 11, 1914) was a German marine Biologist. In Scientific nomenclature, synonyms are different Scientific names used for a single Taxon. "vampire squid from hell") is a small, deep-sea cirrate cephalopod found throughout the temperate and tropical oceans of the world. Vampires are mythological or folkloric revenants who subsist by feeding on the blood of the living Squid are marine Cephalopods of the order Teuthida, which comprises around 300 species Hell, according to many Religious beliefs, is a location in the Afterlife, which may be described as a place of suffering The cephalopods ( Greek plural (kephalópoda "head-feet" are the Mollusc class Cephalopoda characterized by Unique retractile sensory filaments justify the Vampire Squid's placement in its own order: Vampyromorphida (formerly Vampyromorpha), though it shares similarities with both squid and octopuses. This article is about the taxonomic rank for the sequence of species in a taxonomic list see Taxonomic order In scientific classification used Vampyromorphida is an order of Cephalopods comprising one extant species ( Vampyroteuthis infernalis) and several extinct The As a phylogenetic relict it is the only known surviving member of its order, first described and mistakenly identified as an octopus in 1903 by German teuthologist Carl Chun. The term relict is used to refer to surviving remnants of natural phenomena Year 1903 ( MCMIII) was a Common year starting on Thursday (link will display calendar of the Gregorian calendar or a Common year starting Germany, officially the Federal Republic of Germany ( ˈbʊndəsʁepuˌbliːk ˈdɔʏtʃlant is a Country in Central Europe. The cephalopods ( Greek plural (kephalópoda "head-feet" are the Mollusc class Cephalopoda characterized by Carl Chun ( October 1, 1852 – April 11, 1914) was a German marine Biologist.
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Physical description
At a maximum 30 cm (1 foot) in total length, the Vampire Squid is no threat to humans. Its 15 cm (6 inch) gelatinous body varies in color between velvety jet-black and pale reddish, depending on location and lighting conditions. A webbing of skin connects its eight arms, each lined with rows of fleshy spines or cirri; the inside of this "cloak" is black. Only the distal half (farthest from the body) of the arms have suckers. Its limpid, globular eyes—which appear red or blue, also depending on lighting—are proportionately the largest in the animal kingdom at 2. 5 cm (1 inch) in diameter.
Mature adults have a pair of ear-like fins projecting from the lateral sides of the mantle. The mantle is an important part of the anatomy of Molluscs It is the dorsal body wall which covers the visceral mass These fins serve as the adult's primary means of propulsion: Vampire Squid are said to "fly" through the water by flapping their fins. Their powerful beak-like jaws are as white as ivory. Within the webbing are two pouches wherein the tactile velar filaments are concealed. The filaments are analogous to a true squid's tentacles, extending well past the arms; however, they are a different arm pair than the squid's tentacles. Instead, the filaments are the same pair that were lost by the ancestral octopuses.
The Vampire Squid is covered entirely in light-producing organs called photophores. A photophore is a light-emitting organ which appears as luminous spots on various marine animals including Fish and Cephalopods. The animal has great control over the organs, capable of producing disorienting flashes of light for fractions of a second to several minutes in duration. The intensity and size of the photophores can also be modulated. Appearing as small white discs, the photophores are larger and more complex at the tips of the arms and at the base of the two fins, but are absent from the underside of the caped arms. Two larger white areas on top of the head were initially believed to be photophores too, but have turned out to be photoreceptors. Photoreceptor can refer to In anatomy/cell biology Photoreceptor cell: a photosensitive cell most commonly referring to a specialized type of neuron
The chromatophores (pigment organs) common to most cephalopods are poorly developed in Vampire Squid. Chromatophores are pigment -containing and light-reflecting cells found in Amphibians Fish, Reptiles Crustaceans and While this means the animal is not capable of changing its skin colour in the dramatic fashion of shallow-dwelling cephalopods, such trickery is not needed at the pitch-black depths in which it lives. The cephalopods ( Greek plural (kephalópoda "head-feet" are the Mollusc class Cephalopoda characterized by
Habitat and adaptations
The Vampire Squid is an extreme example of a deep-sea cephalopod, thought to reside at aphotic (lightless) depths from 600-900 metres (2,000-3,000 feet) or more. Within this region of the world's oceans is a discrete habitat known as the oxygen minimum zone (OMZ). A habitat (which is Latin for "it inhabits" is an Ecological or environmental area that is inhabited by a particular Species. The Oxygen minimum zone (sometime referred to as the shadow zone) is the zone in which Oxygen saturation in seawater in the Ocean is at its lowest Within the OMZ oxygen saturation is too low to support aerobic metabolism in most higher organisms. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the In Chemistry, saturation has five different meanings In Physical chemistry, saturation is the point at which a Solution of a substance Metabolism is the set of Chemical reactions that occur in living Organisms in order to maintain Life. Nonetheless, the Vampire Squid is able to live and breathe normally in the OMZ at oxygen saturations as low as 3%; a feat no other cephalopod, and few other animals, can claim.
In order to cope with life in the suffocating depths, vampire squid have developed several radical adaptations. Of all deep-sea cephalopods, their mass-specific metabolic rate is the lowest. Their blue blood's hemocyanin binds and transports oxygen more efficiently than in other cephalopods (Seibel et al. Hemocyanins (also spelled haemocyanins) are respiratory Proteins in the form of Metalloproteins containing two Copper atoms that reversibly 1999), aided by gills with especially large surface area. A gill is an anatomical structure found in many aquatic organisms The animals have weak musculature but maintain agility and buoyancy with little effort thanks to sophisticated statocysts (balancing organs akin to a human's inner ear) and ammonium-rich gelatinous tissues closely matching the density of the surrounding seawater. The statocyst is a balance organ present in some aquatic Invertebrates ( Cnidarians Ctenophores Bilaterians) The ear is the sense organ that detects Sounds The Vertebrate ear shows a common biology from Fish to Humans with variations Ammonium is also an old name for the Siwa Oasis in western Egypt. The density of a material is defined as its Mass per unit Volume: \rho = \frac{m}{V} Different materials usually have different
At the shallower end of the Vampire Squid's vertical range, the view from below is like the sky at twilight: The highly sensitive eyes of deepwater denizens are able to distinguish the silhouettes of other animals moving overhead. To combat this, the vampire squid generates its own bluish light (bioluminescence) in a strategy called counterillumination: The light diffuses the animal's silhouette, effectively "cloaking" its presence from the watchful eyes below. Bioluminescence' is the production and emission of Light by a living Organism as the result of a chemical reaction during which chemical energy is converted Its own large eyes detect even the faintest of gleams. A pair of photoreceptors are located on top of its head, perhaps alerting the animal to movements above.
Like many deep-sea cephalopods, Vampire Squid lack ink sacs. An ink is a Liquid containing various Pigments and/or Dyes used for coloring a surface to produce an Image, text, or If threatened, instead of ink, a sticky cloud of bioluminescent mucus containing innumerable orbs of blue light is ejected from the arm tips. This luminous barrage, which may last nearly 10 minutes, is presumably meant to daze would-be predators and allow the Vampire Squid to disappear into the blackness without the need to swim far. The display is made only if the animal is very agitated; regenerating the mucus is costly from a metabolic point of view.
Development
Few specifics are known regarding the ontogeny of the Vampire Squid. Ontogeny, as opposed to Phylogeny, refers to the history of an organism from birth as opposed to its genetic makeup Their development progresses through three morphologic forms: the very young animals have a single pair of fins, an intermediate form has two pairs, and the mature form again has one. At their earliest and intermediate phases of development, there is a pair of fins located near the eyes; as the animal develops, this pair gradually disappears as the other pair develops (Pickford 1949). As the animals grow and their surface area to volume ratio drops, the fins are resized and repositioned in order to maximize gait efficiency. Whereas the young propel themselves primarily by jet propulsion, mature adults find flapping their fins to be the most efficient means (Seibel et al. 1998). This unique ontogeny caused confusion in the past, with the varying forms identified as several species in distinct families (Young 2002).
If hypotheses may be drawn from knowledge of other deep-sea cephalopods, the Vampire Squid likely reproduces slowly by way of a small number of large eggs. Growth is slow as nutrients are not abundant at depths frequented by the animals. The vastness of their habitat and its sparse population make procreative encounters a fortuitous event. The female may store a male's hydraulically implanted spermatophore (a sort of tapered, cylindrical satchel of sperm) for long periods before she is ready to fertilize her eggs. A spermatophore is a capsule or mass created by males of various Animal species containing Spermatozoa and transferred in entirety to the female's Ovipore The term sperm is derived from the Greek word (σπέρμα sperma (meaning "seed" and refers to the male reproductive cells. Once she does, she may need to brood over them for up to 400 days before they hatch. The female will not eat towards this culmination and dies shortly thereafter.
Hatchlings are c. 8 mm in length and are well-developed miniatures of the adults, with some differences. Their arms lack webbing, their eyes are smaller and their velar filaments are not fully formed. The hatchlings are transparent and survive on a generous internal yolk for an unknown period before they begin to actively feed. An egg yolk is the part of an egg which serves as the Food source for the developing Embryo inside The smaller animals frequent much deeper waters, perhaps feeding on marine snow (falling organic detritus). In the deep ocean marine snow is a continuous shower of mostly organic Detritus falling from the upper layers of the water column
Behaviour
What behavioural data known has been gleaned from ephemeral encounters with ROVs; animals are often damaged during capture and survive for no more than about two months in aquaria. Remotely operated underwater vehicles (ROVs is the common accepted name for tethered underwater Robots in the offshore industry An artificial environment makes reliable observation of non-defensive behaviour difficult.
With their long velar filaments deployed, Vampire Squid have been observed drifting along in the deep, black ocean currents. If the filaments contact an entity, or if vibrations impinge upon them, the animals investigate with rapid acrobatic movements. They are capable of swimming at speeds equivalent to two body lengths per second, with an acceleration time of five seconds. However, their weak muscles limit stamina considerably.
Unlike their relatives living in more hospitable climes, deep-sea cephalopods cannot afford to expend energy in protracted flight. Given their low metabolic rate and the low density of prey at such depths, Vampire Squid must use innovative predator avoidance tactics in order to conserve energy. Their aforementioned bioluminescent "fireworks" are combined with the writhing of glowing arms, erratic movements and escape trajectories, making it difficult for a predator to home in.
In a threat response called "pumpkin" or "pineapple posture", the Vampire Squid inverts its caped arms back over the body, presenting an ostensibly larger form covered in fearsome-looking though harmless spines (called cirri). The underside of the cape is heavily pigmented, masking most of the body's photophores. The glowing arm tips are clustered together far above the animal's head, diverting attack away from critical areas. If a predator were to bite off an arm tip, the Vampire Squid can regenerate it.
Copepods, prawns and cnidarians have all been reported as prey of Vampire Squid. Copepods are a group of small Crustaceans found in the sea and nearly every freshwater habitat and they constitute the biggest source of protein in the oceans Prawns are Crustaceans belonging to the sub-order Dendrobranchiata Cnidaria (naɪˈdɛəriə is a phylum containing some 9000 Species of Animals found exclusively in aquatic mostly marine, environments Little else is known regarding their feeding habits, but considering their environment, a fussy palate is unlikely. Vampire Squid have been found among the stomach contents of large deepwater fish, deep diving whales and pinnipeds such as sea lions. Whales are marine mammals which are neither Dolphins (ie members of the families Delphinidae or Platanistoidae) nor Porpoises Orcas Pinnipeds ("fin-feet" lit "winged feet" or fin-footed mammals are a widely distributed and diverse group of semi-aquatic marine Mammals comprising For other uses of the term "sea lion" see Sea lion (disambiguation.
Relationships
The Vampyromorphida are characterized by such apomorphies as the possession of photophores, a peculiar type of uncalcified endoskeleton called "gladius", 8 webbed arms and the 2 velar filaments. Cladistics is the hierarchical classification of Species based on evolutionary ancestry An endoskeleton is an internal support structure of an Animal. Until fairly recently known only from the modern species and some fossil remains tentatively allocated to this group, a batch of Middle Jurassic (Lower Callovian, c. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. The Jurassic is a geologic period and system that extends from about Ma (million years ago to Ma that is from the end of the Triassic to the beginning The Callovian is a stage on the Geologic time scale occurring 164 165-164 mya) specimens found at La Voulte-sur-Rhône demonstrated that clearly vampyromorphid cephalopods were in existence for far longer than has been hitherto believed. In Astronomy, Geology, and Paleontology, mya or " mya " is an abbreviation for "million years ago". La Voulte-sur-Rhône is a commune in the Ardèche department in southeastern France.
These were described as Vampyronassa rhodanica. Vampyronassa rhodanica is an extinct vampyromorph Cephalopod known from around 20 fossils from the Lower Callovian (165–164 The supposed vampyromorphids from the Kimmeridgian-Tithonian (156-146 mya) of Solnhofen, Plesioteuthis prisca, Leptoteuthis gigas, and Trachyteuthis hastiformis, cannot be positively assigned to this group; they are large species (from 35 cm in P. The Kimmeridgian is a stage of the Late Jurassic Epoch. It spans the time between 155 The Tithonian is the final stage of the Late Jurassic Epoch. It spans the time between 150 Solnhofen is a municipality in the district of Weißenburg-Gunzenhausen in the region of Franconia in the Land of Bavaria in Trachyteuthis hastiformis is an extinct species of Cephalopod, currently the only member of its Genus. prisca to > 1 meter in L. gigas) and show features not found in vampyromorphids, being somewhat similar to the true squids, Teuthida (Fischer & Riou 2002). Squid are marine Cephalopods of the order Teuthida, which comprises around 300 species
References
- Bolstad, Kat (2003): Deep-Sea Cephalopods: An Introduction and Overview. Version of 5/6/03, retrieved 2006-DEC-06.
- Ellis, Richard (1996): Introducing Vampyroteuthis infernalis. In: The Deep Atlantic: Life, Death, and Exploration in the Abyss. Alfred A. Knopf, New York. ISBN 0679433244. Online version retrieved 2007-APR-30.
- Fischer, Jean-Claude & Riou, Bernard (2002): Vampyronassa rhodanica nov. gen. nov sp. , vampyromorphe (Cephalopoda, Coleoidea) du Callovien inférieur de la Voulte-sur-Rhône (Ardèche, France). Annales de Paléontologie 88(1) 1−17. [French with English abstract] doi:10.1016/S0753-3969(02)01037-6 (HTML abstract)
- Pickford, Grace E. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. (1949): Vampyroteuthis infernalis Chun an archaic dibranchiate cephalopod. II. External anatomy. Dana Report ""32"":1–132.
- Robison, Bruce H. ; Reisenbichler, Kim R. ; Hunt, James C. & Haddock, Steven H. D. (2003): Light Production by the Arm Tips of the Deep-Sea Cephalopod Vampyroteuthis infernalis. Biological Bulletin 205(2): 102-109. PDF fulltext
- Seibel, Brad A. (2001): Vampyroteuthis infernalis. Retrieved 2006-DEC-06.
- Seibel, Brad A. , Thuesen, Erik V. & Childress, James J. (1998): Flight of the vampire: ontogenetic gait-transition in Vampyroteuthis infernalis (Cephalopoda: Vampyromorpha). Journal of Experimental Biology 201: 2413-2424. PDF fulltext
- Seibel, Brad A. ; Chausson, Fabienne; Lallier, Francois H. ; Zal, Franck & Childress, James J. (1999): Vampire blood: respiratory physiology of the vampire squid (Cephalopoda:Vampyromorpha) in relation to the oxygen minimum layer. Experimental Biology Online 4(1): 1-10. doi: 10.1007/s00898-999-0001-2 10.1007/s00898-999-0001-2 (HTML abstract)
- Young, Richard E. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. (2002): Taxa Associated with the Family Vampyroteuthidae. Version of June 2002, retrieved 2006-DEC-06.
External links
- CephBase: Vampire Squid
- Tree of Life: Vampyroteuthis infernalis. The Tree of Life Web Project is an ongoing Internet project providing information about the diversity and Phylogeny of Life on Earth
- National Geographic video of a Vampire Squid
Images
- Image with velar filament in view, detailed caption
- The vampire squid's photophores and photoreceptors
- Diagram and images of a Vampyroteuthis hatchling
- Photomicrograph of arm tip fluorescence
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