Deep Sea Hydrothermal Vent Communities

1. Deep Sea Hydrothermal Vent Communities Mrs. Stahl

2. The Deep Sea • The ocean is defined by depth • All have different • Characteristics • Properties • Ecosystems • Our focus today: • > 1000 m

3. Ocean Conveyor Belt

4. Ocean Conveyor Belt • This is the interplay of water through the world’s oceans. • Takes 1600 years for one drop of water to go through the loop. • The drops of water get caught up in gyres (area of rotating currents) and seas. • Extremely important to the deep sea because it brings nutrients and allows upwelling to occur. • Upwelling= Winds blowing across the ocean surface push water away. Water then rises up from beneath the surface to replace the water that was pushed away (www.noaa.gov). The water is colder and full of rich nutrients.

6. http://www.youtube.com/watch?v=h6i16CrI8ss

7. Deep Sea Properties • Depth: >1000m • Pressure: high; may exceed 1000 atm (1 atm=10m) • Temperature- Thermocline (zone of rapid temperature change) • Deep Sea Temps-= 2 Celsius but can be much greater • Hydrothermal Temps= 400 Celsius • Chemosynthesis • Light amounts: dark- aphotic zone begins at ~ 1000m • Density: increases with depth • Live about 7-10 years • Rely on Hydrogen sulfide

8. Vent Chemistry Fallout of precipitated MnO2 and FeO(OH) Precipitation of FeS, CaSO4, CuFeS2 Basalt

10. Discovered in 1977 by Bob Ballard • Was in the Alvin and he saw a shimmery object. He put a probe in it and it melted.

11. How does a vent form? • Hot vent fluid mixes with cold seawater causing a series of chemical reactions to occur. • Example -sulfur in some vent fluid combines with the metals, forming sulfide minerals. When the mixing occurs as the fluid exits the seafloor, the minerals precipitate to form chimney-like structures that project (sometimes for several meters) into the surrounding ocean. • Bacteria covers the area attracting other small organisms such as amphipods and copepods.

12. Chemosynthetic Bacteria of the Vents • 6CO2 + 6H2O + 3H2S -> C6H12O6 + 3H2SO4 • Use energy contained in HS- to make organic material • Bacteria are the base of the vent food chain

13. Tube Worms Riftia worm Size: up to 6 ft- 10 ft. Thought they were clams Red plume acts like gill- exchanges CO2, O2, H2S with water Special organ filled with symbiotic bacteria that perform chemosynthesis which pass organic matter to worm. They actually don’t eat but house the bacteria in their guts.

14. Why are the vents important? • Oasis of life, about 300 species have been identified. A new organisms is discovered every 10 days. • Doesn’t depend on photosynthesis- perhaps life didn’t begin by photosynthesis, but through chemosynthesis. • May provide information on the formation of life. • Think there may be more biomass in our crust.

15. Deep Sea Adaptations • Small. Less than 10cm. Example- Ogre fish (Fang tooth) which is 4 cm. • Reduced or no swim bladder • Bioluminescence- 95% of all ocean animals • Large mouths- eat large things, they may not eat for a while • Hermaphroditic- need to change sexes • Dark coloration- red = can’t see me, many are flabby, some are clear

16. Why are they small? • Not a lot of food-> don’t spend their energy on being large, they need to move, reproduce, and conserve energy.

17. Dragonfish • Has red bioluminescence • Signals to others-> food, mates • Still researching

18. Deep sea Lizardfish Dragonfish Gulper Eel Hairy Anglerfish

19. Anglerfish Anglerfish

20. Pearleye Fish Dragonfish

21. Redmouth Whalefish

22. Lancetfish Hatchetfish

25. Uses density and pressure differences to suspend itself in the water. Giant Sea Spider Greenland Sleeper Shark

26. Ctenophore Jellyfish

27. Deep Sea Spider Deep Sea Squid

28. The Deep Seafloor

29. Deep sea sea urchin Deep sea seastar and sea spider Deep sea cucumber

30. Tripod fish Chimaera

31. Deep-sea amphipods • Found near baitfall (any carcass that dies). Always first to the dead stuff. • Well developed sense of smell • Expandable gut • Bring them to the surface they explode

32. Videos • http://www.youtube.com/watch?v=S3CJIKKSUpg • http://www.youtube.com/watch?v=UXl8F-eIoiM • http://www.youtube.com/watch?v=D69hGvCsWgA • http://www.youtube.com/watch?v=xQP5yV9yxFc • http://ocean.nationalgeographic.com/ocean/photos/deep-sea-creatures/#/deep-sea05-six-gill-shark_18165_600x450.jpg • http://www.discovery.com/tv-shows/curiosity/videos/first-video-of-a-giant-squid.htm

33. Bioluminescence Dinoflagellates Trinidad

34. Ocean Zones 100m dysphotic

35. Light penetration in the ocean The Electromagnetic Radiation Spectrum Only green and blue wavelengths pass through water -about 100 meters

36. Light Penetration in the Ocean

37. What organisms that you know of have bioluminescence? Bioluminescence evolved in several kingdoms. Evolution: In early evolution, O2 was toxic. Some organisms were able to convert it to a nontoxic substance, which had the tendency to produce photons of light. This may have had a selective advantage to some organisms. Not found in freshwater organisms.

38. Bioluminescence Chemical Reaction luciferase Luciferin + O2Oxyluciferin+ light

39. Photophore (bacterial / symbiotic) Light emitting organ that can’t be controlled or turned on and off.

40. Examples of Bacterial Photophores: • fish, few squid, Pyrosoma (tunicate) • How do they get bacteria? • organ open to exterior (provide entrance for bacteria to enter) • potentially continuous luminescence Pyrosoma

41. Examples of fish that have bacterial photophores: • Anglerfish (ceratioids) • Pinecone fish (Monocentrids) • Lantern eyes/flashlightfish (Anomalopids) • Ponyfishes/slipmouths (Leiognathids) • Ichthyococcus

42. Flashlight Fish • Has a flap to cover its glowing qualities.

43. Cephalopod Photophore

44. Photophores • Cephalopods possess a great variety • Some are very small and complex less than .2 mm, while others are large. • Wide range in structure from a simple group of photogenic cells to organs with photogenic cells surrounded by reflectors, lenses, light guides, color filters and muscles. • http://www.youtube.com/watch?v=BtQGslJjLdc

45. Complex photophores are often able to actively adjust the color, intensity and angle of the light they produce. • Photophores of most oceanic cephalopods have intrinsic luminescence with the light coming from their own specialized cells, the photocytes. • Photophores of most neritic cephalopods, in contrast, have extrinsic luminescence with the light produced by bacteria that are cultured in specialized light organs of the host cephalopod.

46. Chromatophores • Pigment cells that absorb light leaving the photophore in undesirable directions or that shield the reflectors of the photophore, when the photophore is not active, from reflecting external light that could reveal the presence of the cephalopod.

47. Color Filters • Structures within a photophore that restrict the color of the light emitted by the photocytes. Filters can either rely on selective absorption of light (pigment filters) or selective transmission/reflection of light (iridophores).

48. Lenses • A variety of structures that apparently affect the directionality of light are called "lenses." Some of these appear to act like typical optical lenses but the mode of action of others (like those in the illustration to the right) are uncertain.

49. Light Guides • Structures that control the direction of emitted light through the use of "light pipes" that rely on total internal reflection. These function in the same manner as fiber-optic light guides.

50. Photocytes • Photocytes - Cells that produce light (i.e., the bioluminescence).