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Friday, April 16, 2010












Goblin Shark:


--Of all the sharks that are found in the deep trenches of the ocean, the goblin shark is probably the scariest looking.

· Goblin sharks can grow to be 11 ft in length and possess what may be the most alien trait in the entire ocean: protrusible jaws.

· Goblin sharks have flabby, pinkish grey bodies with large anal fins.

· Because goblin sharks are so rare there is not much information about their reproduction habits. It is widely believed that goblin sharks are ovoviviparous, meaning that they produce eggs with embryos and their young hatch outside of the female.

· There is even less knowledge about what a goblin shark eats, though it is believed that they feed mainly on soft body prey as suggested by their long, thin teeth which meant for ripping and tearing, not crushing.

· Goblin sharks have been found mainly off the coast of Japan, South Africa and New Zealand and are usually brought up by deep sea fishing trawlers.

· They are not thought to be endangered as they rarely come into contact with humans.

Anglers:







· There are more than 200 species of anglerfish, most of which live in the murky depths of the Atlantic and Antarctic oceans.

· Some angler fish can be quite large, reaching 3.3 feet (1 meter) in length. Most however are significantly smaller, often less than a foot.

· Their most distinctive feature, worn only by females, is a piece of dorsal spine that protrudes above their mouths like a fishing pole. Tipped with a lure of luminous flesh this built-in rod baits prey close enough to be snatched. Their mouths are so big and their bodies so pliable, they can actually swallow prey up to twice their own size.

· In lieu of continually seeking the vast abyss for a female, it has evolved into a permanent parasitic mate. When a young, free-swimming male angler encounters a female, he latches onto her with his sharp teeth. Over time, the male physically fuses with the female, connecting to her skin and bloodstream and losing his eyes and all his internal organs except the testes. A female will carry six or more males on her body.

Shark’s Liver:

· Compared with other animals, the liver of sharks is very large – typically accounting for 15 to 25% of the total body weight

· The liver banks vitamins for release in times of low supply, manufactures a starch-like compound that is used as a fuel supply by white muscle and can be used by other tissues in an emergency, stabilizes the body's blood-sugar level, detoxifies poisons, builds enzymes, processes digested fats, manufactures bile and cholesterol, and constitutes a major source of metabolic heat.

In sharks, the liver is perfused with low-density oils and hydrocarbons. One of the most important of these hydrocarbons is squalene (C30H50), which is much less dense than seawater. Because sharks lack a swim bladder, sharks are heavier than water. The collective effect of the low-density compounds in the shark liver is to provide lift by reducing its overall density. As a result, a shark is only very slightly more dense than sea water, making a 'typical' shark only slightly heavier than the medium through which it swims.



· Biobliography:

· http://www.elasmo-research.org/education/white_shark/digestion.htm

· http://animals.nationalgeographic.com/animals/fish/anglerfish.html

· http://www.elasmodiver.com/Sharkive%20images/AtlanticSharpnoseSharkLiver001.jpg

· http://img.allposters.com/6/LRG/21/2142/VBQED00Z.jpg

· http://whyevolutionistrue.files.wordpress.com/2009/02/p5249wmu.jpg\

· http://www.flmnh.ufl.edu/FISH/Gallery/Descript/GoblinShark/GoblinShark.html

· www.teara.govt.nz/en/sharks-and-rays/4

· http://www.elasmo-research.org/education/shark_profiles/m_owstoni.htm

Thursday, April 8, 2010

Bioluminescense

Bioluminescence is defined as the light produced by a chemical reaction which originates in an organism. This feature can occur at any depth or any sea, but it is essentially absent from fresh water environments. Bioluminescence is the predominant source of light in the deep sea. The majority of organisms that inhabit the upper 6500 feet of the ocean waters are capable of producing some kind of light. The most common occurrence for the human eye is when sailor is in the bow wave or wake of a surface ship. This bioluminescence is due to the dinoflagellates, single-celled algae. This happens due to the algae being mechanically excited to produce light by the ships passage and movement of other fish. The chemistry behind the interesting feature is that the firefly enzyme luciferase catalyzes the formation of a luciferin (light emitting biological pigments) and an ATP complex known as luciferyl adenylate. This complex is oxidized by oxygen, leading to the production of a cyclic peroxide that eventually becomes high-energy oxyluciferin (which is originally in an excited state). Once the oxyluciferin releases energy, light is emitted. The lantern nerves of the organism triggers the release of octopamine, a neurotransmitter that causes the firefly lantern to initiate the luciferin reaction. This ultimately produces light. There are many theories to prove this including: the NOS Model, the Osmotic Control Model, and the Hydrogen Peroxide Model. It is important to note that Bioluminescence is effective only if other organisms can see it. Bioluminescent organisms primarily use their special features in order to find and attract prey, defend against predators, and communicate to other organisms. For instance, bioluminescence is used to startle, misdirect, alarm, stun or confuse, lure, or simply just to attract mates. Many of the organism in the deep ocean can produce anywhere from 440 nm and 479 nm of light. There are a few organisms that produce light continuously, but most emit light of durations from about 0.1 second to a long10 seconds. Examples of bioluminescent marine life: Coral, comb jellies, some clams, sea pens, anglerfish, cookie-cutter shark, gulper eel, vampire squid, colossal squid just to name a few.

Videos:
http://www.youtube.com/watch?v=UXl8F-eIoiM

http://www.youtube.com/watch?v=_QUt-Rrs6Co

-Chase Davis & Jake Turrin

Hydrothermal Vents; How Do Organisms Survive?

Hydrothermal Vents are located on the deep sea floor and are formed when tectonic plates are moving apart from each other. After the separation of these plates, cold ocean water permeates through the sea floor. The cold water “undergoes a series of chemical reactions with subsurface rocks at various temperatures to create hot hydrothermal fluid that eventually vents at the seafloor.”[1] Along with the hydrothermal fluid that is produced, these vents also release deadly toxins, which ironically are essential for life near these vents. One of the most important gases that the vent produces is hydrogen sulfide. While hydrogen sulfide is usually a harmful gas, the microbes and organisms on the deep sea floor near these vents, thrive on it. When the hydrothermal vent produces hydrogen sulfide, it reacts with the oxygen in the water. This reaction releases energy, which the microbes use to then create organic compounds.
The larger organisms near these vents then use the organic compounds in different ways depending on their anatomies. Tubeworms, for example, use the plume from the hydrothermal vent to take up sulfide and oxygen. The worms take in the nutrients through their tips. These nutrients are then relayed through their bloodstream to the microbes located in the worm’s tissue. These microbes then convert the nutrients into organic compounds which the worms then use as energy to make food for themselves. Another organism found on the deep sea floor near hydrothermal vents is the Yeti crab. The crab was first discovered in an expedition in the southeast Pacific Ocean lead by MBARI scientist Bob Vrijenhoek. The group of scientists observed that the Yeti crab chose to reside under and behind rocks much like their distant relatives, hermit crabs. These crabs, like the tube worms, have found ways to “incorporate the sulfur-loving bacteria within their bodies, so that they too can obtain nutrition from the chemicals flowing up out of the sea floor.”[2]



To learn more about hydrothermal vents and listen to Bill Nye talk about the discovery of such vents, click this link.


[1] Humphris, Susan E. & McCollom, Thomas. The Cauldron Beneath the Seafloor. Oceanus, The Mid Ocean Ridge, Part 2. Vol. 41. No 2. 1998. pp 19

[2] Fulton-Bennett, Kim. Monterey Bay Aquarium Research Institution. March 2006. Discovery of the “Yeti Crab”. April 2010. http://www.mbari.org/news/homepage/2006/yeti-crab.html

The Bathysphere is basically a sphere that was attached with a steel cable to the main ship. Maneuverability of the Bathysphere was very limited, only moving up and down. If this cable snapped, the Bathysphere would plummet down to the depths of the abyss of the deep blue ocean. The Bathysphere was the first time humans were able to explore the deep ocean, setting a record for the deepest dive during that time – 3,200 ft (992 meters) .


In 1937, Auguste Piccard had designs for a Bathyscaphe which was essentially an improved version of the Bathysphere. It was in the shape of a small gondola made of steel, and there was a large compartment attached to the gondola that was filled with gasoline. The gasoline was used as buoyancy since it was lighter than water. There was also tons of ballast in the compartments used to weigh down the Bathyscaphe. The Bathyscaphe was a huge improvement from the Bathysphere because it was not attached to a steel cable and the submarine was able to explore at its own will. This submarine could dive up to 10,000 ft (3,048 meters) . On January 23rd 1960, Jacques Piccard, Auguste’s son, and Donald Walsh, a US Navy Lieutenant, piloted the Trieste to the bottom of Challengers Deep, the deepest part of the Marianas Trench. It took the vessel 4 hours and 48 minutes to reach the bottom of the trench at about 35,800 ft. The expedition of the Trieste allowed scientists to learn about the geology of the Marianas Trench, and they realized that the ocean bed was able to sustain marine life as their mercury lamps reflected small, red shrimp like creatures. After sitting at the bottom for 20 minutes, they released the ballast and started their ascent journey which was shorter than the descent trip – 3 hours and 17 minutes.

Symbiosis Around Deep Sea Tube Worms!


Adult tube worms, close relatives to the earthworm, are tall red and white tubelike structures. They maintain their rigid structure from a thick outer layer of chitin, the same material found in the shells of shrimps. Although tube worms do not have mouths or stomachs, they are able to grow nearly a meter per year, making them the fastest growing marine invertebrates. They do this by growing only around hydrothermal vents, the places on the deep sea ocean floor with the most abundant supply of the nutrients they need to survive. In this environment, they are able to work alongside a specific group of creatures to ensure all of their survival. On the smallest side of the spectrum, microbes that live inside the tube worm's organ called the trophosome take in all of the tube's nuturients for them. They do this by using the chemicals, such as hydrogen sulfide, oxygen, and carbon dioxide, that tube worms take in to perform chemeosymbiosis and produce sugars. In return, the tube's provide very effective shelters to the microbes, and, as an added bonus, to many other small creatures who find solace weaving inbetween entire forests of these worms that cover hydrothermal vents. In fact, large populations of crabs have been found to be living amongst these worms occasionally feeding on their red plumes. Along with clams and mussels, these crabs are known to obtain hydrogen sulfide from the hydrothermal cracks for the microbes that live in their gills. The microbes are also known to be foodsource for invertabrates like the blind Atlantic vent shrimp. Others, such as eel pouts, Vulcan octopi, Brachyruan crabs, are opportunistic feeders that eat both living and dead organisms.Although the sybiosis apparent in the communities around tube worms is the most widely understood, marine biologists believe that similar relationships exist in more than 100 species of marine invertebrates.


image source:
http://www.amnh.org/learn/courses/ocean_resource17.php

i.livescience.com/images/ig29_spider_crabs_09.jpg

The Vampire Squid from Hell














The vampire squid, which is not technically a true squid, is named for its blue eyes, reddish-brown skin and webbing between the arms. It is relatively small measuring up to 28cm long. A unique character of the vampire squid are its photophores. These photophores are organs all over the body which produce luminescent clouds of glowing particles. The body composition of the vampire squid is similar to that of a jellyfish. It has very large eyes; proportionally it has the largest eye to body ratio of any animal in the world. The vampire squid has weak muscles, however it can swing quickly using its fins for a short period of time. It swims at an estimated 2 body lengths per second. The squid is found in temperate and tropical parts of the ocean. It is a carnivore and eats copepods, prawns, and cnidarians. The female vampire squid is larger than the male. Not much is known of the reproductive functions of the squid. It is thought that they reproduce slowly by laying eggs. The squid is found as shallow as 300 ft and as deep as 3000 ft. The vampire squid is an incredibly mysterious creature that has yet to be thoroughly investigated, because as is the case with many deep sea creatures, they observed in the wild.

Here are three great videos on the Vampire Squid:

Vampyroteuthis "vampire squid from hell" - Planet Earth

Sources:
http://marinebio.org/species.asp?id=179
http://www.seasky.org/deep-sea/vampire-squid.html
http://www.dfg.ca.gov/QandA/images/20081023/vampire_squid.jpg

By James And Gustavo