Monday, April 26, 2010
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
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?
[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
Wednesday, April 7, 2010
SIPHONOPHORES
In siphonophores, zooids take on specific responsibilities. For example, the medusae, which are responsible for allowing siphonophores to swim through water, aren’t helping in eating.
This is a sweet vid of a siphonophore. Check it out
http://siphonophores.org/index.php
Symbiosis Around Deep Sea Tube Worms!
image source:
http://www.amnh.org/learn/courses/ocean_resource17.php
i.livescience.com/images/ig29_spider_crabs_09.jpg