Power point on The Goblin shark , the retractable jaw, shape and colour of body as well as the electro-sensitive organs for finding prey - PowerPoint Presentation Example

Slide This presentation is about the physiology and adaptations of the goblin shark, Mitsukurina owstoni, as well as its feeding habits, prey, and distribution patterns in the world’s oceans. Slide 2 For the overview, the following shall be the content of the presentation. The taxonomic classification of the species, its habitat and distribution, prey and feeding habits, as well as its unique morphological adaptations. The descriptions regarding the goblin shark shall be summarized at the end of this presentation.

Slide 3 The goblin shark was named by David Jordan in 1898, after the Japanese researcher Kakichi Mitsukuri, who discovered it in the catch of fishermen around the bay of Tokyo. The shark was considered to be the sole living species from its own family of Mitsukuridinae, which are mostly found as fossils. The goblin shark’s classification is as follows: it is from the kingdom Animalia, under the phylum chordata, class chondrichthyes, the cartilagenous fishes, subclass elasmobranchii, order lamniformes, family mitsukurinidae, genus mitsukurina, and species owstoni.

The English common name is goblin shark, and its Japanese name is Ten-gu za-me, which is literally translated as goblin shark, due to the protruding snout. Slide 4 The goblin shark is mostly seen in the coastal areas of Tosa Bay and Boso Peninsula in Japan, where it was first seen. They are demersal, meso-pelagic to benthic, and are mostly found in the bottom of the ocean floor, as evidenced by fishermen catching them in nets that are dragged on the bottom of the ocean. They can be found as deep as 2000m.

They are mostly found in temperate areas, but are also found around the tropics, as shown in the succeeding slide. Slide 5 As seen from the distribution pattern, in yellow, these are the areas where sightings of the goblin shark are recorded from mostly sparse literature available. Because of the inability of the shark to live in aquariums, presumably due to its adaption in living at great depths, other parts of its life cycle such as reproduction and growth are remained in obscurity. However, examining the bowels of dead goblin sharks have made their feeding habits and prey known.

Slide 6 As apex predators of the ocean, goblin sharks are just like other sharks that have electro-sensitive organs called the ampullae of Lorenzini, which detect the motions of prey near the ocean floor. Their retractable jaws suck in prey, and with the combination of their blade-like teeth prevent the prey from escaping. They are also known to be nocturnal, due to some sightings of them surfacing the waters at night. Slide 7 The prey most found in the stomachs of the goblin sharks that were caught were small, mesopelagic teleosts such as lantern fish, myodocopid ostracods, much like zooplankton, small or juvenile squids, as well as crabs and other crustaceans.

Slide 8 The goblin shark has body structures similar to other sharks like having a fusiform or tapered body shape, fins, sharp teeth, eyes, etcetera. However, what makes the goblin shark unique are its thresher or heterocercal tail, small eyes that have adapted to living at great ocean depths, pink or lightly-colored skin that is rather flabby but becomes turgid at great pressures under the sea, and its protruding snout called a rostrum, as well as its notable retractable jaws lined with flat, blade-like teeth.

Slide 9 This is the typical body shape of a goblin shark. As seen from the photograph, it has a protruding rostrum, a thresher-like tail, retractable jaws, pink, flabby skin, and rounded dorsal, ventral and caudal fins. Slide 10 This is the zoomed-in strong features of the goblin shark’s head, showing its unique characteristics of slender teeth, pink skin, retractable jaws, and the notable rostrum. Slide 11 This following video from youtube shows a diver that is being attacked by the goblin shark.

Note the retractable action of its jaws, as well as its overall shape when swimming. Because of its shape, it is more suited to skimming or swimming at the bottom, as opposed to other sharks such as the great white or mako, whose body features are much more tapered for rapid movements in the water. The video is in Japanese, but most of the descriptions in the video were already discussed in the previous slides.Slide 12 To summarize, the goblin shark is a prehistoric fish, from the group where sharks also belong, and a sole member of its family, Mitsukurinidae.

Its unique adaptive features are its retractable jaws, elongated snout or rostrum, pink and flabby skin, as well as its small eyes, which are all suitable to its environment in the bottom of the ocean floor, where there is a high pressure exerted by the water. Its prey are mostly bottom-dwelling animals such as lantern fish, crustaceans and young squid. The goblin shark can be found mostly in Japan, as well as other coastal areas around the tropical and temperate latitudes. While the feeding habits and areas of distribution are known, due to the goblin shark’s tendency to die when being held in aquariums make its other life cycle aspects obscured, as well as few literature available to explain other aspects of its life cycle.

Slide 13 The following are references for the facts as well as pictures presented in this slideshow.