Deep Sea Hydrothermal Vent Communities
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Transcript of Deep Sea Hydrothermal Vent Communities
Deep Sea Hydrothermal Vent
Communities
Mrs. Stahl
The Deep Sea• The ocean is defined by
depth
• All have different • Characteristics• Properties• Ecosystems
• Our focus today: • > 1000 m
Ocean Conveyor Belt
Ocean Conveyor Belt• This is the interplay of water through the world’s oceans, constant
motion.• Motion is caused by thermohaline currents (thermo=
temperature, haline = salt) in the deep ocean and wind driven currents on the surface.
• Cold, dense water sinks to the bottom while the less dense warm water stays on the surface.
• “Starts” in the Norwegian Sea where warm water from the Gulf Stream heats the atmosphere in the cold northern latitudes. This loss of heat to the atmosphere makes the water cooler and denser, causing it to sink to the bottom of the ocean. As more warm water is transported north, the cooler water sinks and moves south to make room for the incoming warm water. This cold bottom water flows south of the equator all the way down to Antarctica. Eventually, the cold bottom waters return to the surface through mixing and wind-driven upwelling, continuing the conveyor belt that encircles the globe. http://oceanservice.noaa.gov/facts/conveyor.html
• 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.
• Takes around 1600 - 2000 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.
http://www.youtube.com/watch?v=h6i16CrI8ss
• 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
Deep Sea Properties
Pressure
• Fluid pressure in the deep sea animals tissues matches the pressure of the surrounding water. Tissue fluid pressure pushes against the surrounding pressure with an equal but opposite force, preventing the animals body from being crushed.
Cold Temperatures
• Low body temperature = low metabolism• Animals move slower and grow slower• Reproduce less frequently• Require less food• Advantage of cold-> Increased density of the
water -> body densities are close to that of the water so they don’t have to expend energy to keep from sinking
Googleimages
Oxygen
• Adequate oxygen because cold water can dissolve more oxygen than the warmer, deepest waters generate from shallow polar seas.
• Northern and Southern Seas= thermohaline currents = oxygen rich waters cool off so much that they become dense enough to sink to the bottom.
Color
• Those that live in the well lit areas adapt by countershading -> dark dorsal surface and lighter ventral to blend in.
Diphotic / Twilight Zone
• 150-450 meters (500-1500 ft.) -> there is still enough light to use countershading as camouflage
• Ex- Hatchetfish
Photophores
• Light producing organs located all along their body
• Aids in species recognition and bioluminescence may make the ventral surface lighter = camouflage
Twilight Zone and Below
• Variety of colors:– Iridescent sheen – Black and brown – Deep reds and purples– Bioluminescent– White (Benthic)– Red and Orange appears to be black and gray in
depths
Bioluminescence• Animals found between 300-2400 m. (1,000- 8,000 ft.)• Squid, crustaceans, fish -> have their own
luminescent organs• Others harbor bacteria (mutualism)= light for the host
and the bacteria have a place to live / feed.• Some can control bioluminescence by altering the
flow of oxygenated blood to the regions where the bacteria lives.– Increased oxygen levels = glow– Decreased oxygen levels = no glow
Why and how does bioluminescence occur?
• Occurs because of luciferin, a protein, that combines with oxygen in the presence of luciferase and ATP
• The chemical energy of ATP is converted into light energy.
• Very efficient, almost 100% light, no heat• Most light is blue / green, some reds and
yellows have been reported
Luminescent Organs
• Rows of photophores along their sides or bellies
• Depressions on their head or growths coming out of the top of their head
• Deep Sea Squid- spots on their tentacles
Mating / Species Recognition
• Patterns of light identifies an individual as being male or female.
• A series of light flashes means they are ready to mate.– Ex.- Lanternfish-> males carry bright lights at the
tops of their tails, whereas females have only weak lights on the underside of their tails.
– Species identification- lanternfish have three rows of light spots, where another species may have two.
Male and Female Lanternfish
http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAYQjB0&url=http%3A%2F%2Fanimal-kid.com%2Flanternfish.html&ei=AF3-VPDlMYi4ggT_2IPgBQ&bvm=bv.87611401,d.eXY&psig=AFQjCNF_5F_qKHI6gLrB5mnGjmAYK5152g&ust=1426042495975107
Attracting Prey
• Anglerfish and Stomiatoids attract prey with lures
• Ventral surface lights up = see their prey• Lights around their eyes that illuminate
whatever the fish looks like.• https://www.youtube.com/watch?v=XUVerZ
sbYiw
Defense
• Squid release a bioluminescent fluid that clouds the water with light confusing predators.
• Opossum shrimp- female carries her eggs in a pouch under her thorax and when threatened they release a substance that bursts into a cloud of mini light particles that look like stars in the sky.
• https://www.youtube.com/watch?v=9HXXQBz6Vv0
Seeing in the Dark
• Normal vertebrate eye spheroid / one retina• Deep Sea= tubular and contain 2 retinas• Retina 1= See distance• Retina 2= See close up• Allows them to see better in dim light and
have good depth perception. They can judge the distance of their prey better so they won’t miss it. This is a HUGE ADVANTAGE!
• At depths between 900-1500 m. the eyes are smaller and less functional.
• Ex- Anglerfish: it begins life in well lit areas and as they become an adult they sink and live in the depths, about 1800 meters. The eyes stop growing and degenerate.
Finding Mates• Anglerfish: males bite the female and remain
attached, sometimes forever (lifelong parasite). The skin around the males mouth and jaws fuses with the females body and only a small opening remains on either side of the mouth for gas exchange.
• The eyes and most of the internal organs degenerate and the circulatory system becomes connected to the females. The male is just an external sperm producing appendage.
• Females have lures• Males have teeth (snout and chin)
Finding Food• Food is scarce• Feed on organic waste, dead organisms, and
scraps• Detritus feeders are key prey in the deep sea
food web• Many rise at night to feed in the nutrient rich
waters, returning during the day (vertical migrations)
Gulper Eels
• Hinged jaws (trapdoor) and stomachs that can expand to several times their size.
• The tip of the tail is bioluminescent and may be used to attract prey.
Stomiatoids – Black Sea Dragon• Ingest prey larger than itself• Most species are 6-7 inches long• Large heads, curved fang like teeth and
elongated bodies that tapers into a small tail
More about Black Sea Dragons
• Barbel- fleshy projection that dangles below its chin / throat. It varies from species to species.– Some are short hairs– Some are whip-like structures– Many are bioluminescent
• Unknown function but may be used as a lure, to probe bottom ooze for food, or species identification during mating.
Anglerfish
• Lure at the tip that is a modified dorsal spine- acts like a fishing pole, lies in a groove on top when it’s not used.
Giants of the Deep
• Most are small but there are some large ones- perhaps because they live longer and can grow more.
• Ex- Sea Urchins (30 cm. = 1 ft.)• Ex- Hydroids (8 ft. high)
http://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&uact=8&ved=0CAYQjB0&url=http%3A%2F%2Foceanexplorer.noaa.gov%2Fexplorations%2F05fire%2Flogs%2Fapril22%2Fmedia%2Furchins.html&ei=nfAAVd76LcOdgwSO_oKADQ&bvm=bv.87920726,d.eXY&psig=AFQjCNGiKwq3L2guBI1jfZGaALmQZYxeuA&ust=1426211342851320
http://www.schmidtocean.org/story/show/1394
Giant Squid• Architeuthus• Largest invertebrate: 9-16 m. (30-53 ft.)• Arms are as thick as a human thigh• Thousands of suckers• Two tentacles: 12 m. (40 ft.long)• Possibly weigh 1 ton• http://www.ted.com/talks/edith_widder_ho
w_we_found_the_giant_squid#t-228725
Vampire Squid
• Webbing between the arms and dark color cloak like a vampire
• They think it avoided extinction by retreating to the bottom of the ocean while its ancestors died 100 mya
• Soft muscles / poor development = bad swimmer, most likely drifts
• Bioluminescent organs that are covered by large flaps of skin
• http://video.nationalgeographic.com/video/news/squid-vampire-threatened-vin
http://www.amazingandweird.com/facts/vampire-squid-facts-20-facts-about-vampire-squid/
Life on the Bottom- Benthic Communities
• Biggest struggle-> availability of food • No photosynthesis, cold temps• Slow bacteria growth• Base of the food chain is vey limited / non-existent• Food consists of whatever falls from above ->
particles, carcasses, feces, and organic matter• Turbidity currents deliver organic nutrients to
abyssal plains and trenches
Food Chains
• Meiofauna-> small benthic invertebrates• Ex- foraminifera and nematode worms feed
on bacteria, organic matter, and each other.
Infauna• Animals living in the sediment of the ocean floor• Ex- Larger worms and bivalves feed on meiofauna.• Deposit feeders • Deep sea bivalves use siphons to suck food up on
the sediment• Other deposit feeders-> sea cucumbers (sea pig),
brittlestars, and urchins dominate the landscape• Giant crinoids and sea pens -> suspension feeders• Predators= fish, squid, sea stars• Mid-ocean trenches-> food is scarce, even tiny
organisms are rare
Vent Chemistry
BasaltPrecipitation of FeS,CaSO4, CuFeS2
Fallout of precipitated MnO2 and FeO(OH)
• Discovered in 1977 by Bob Ballard
• Galapagos• Was in the Alvin and he saw a
shimmery object. He put a probe in it and it melted.
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.
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
Tube WormsRiftia worm
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.
Red plume acts like gill- exchanges CO2, O2, H2S with water
Size: up to 6 ft- 10 ft.Thought they were clams
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.
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
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.
Dragonfish• Has red
bioluminescence• Signals to others->
food, mates• Still researching
Hairy Anglerfish Gulper Eel
Dragonfish
Deep sea Lizardfish
Anglerfish
Anglerfish
Pearleye Fish Dragonfish
Redmouth Whalefish
Lancetfish
Hatchetfish
Vulcan Octopus
Flashlight Fish
Dragonfish
Sea Pig
Cusk Eel
Deep Sea Lobster
Giant Sea Spider
Greenland Sleeper Shark
Uses density and pressure differences to suspend itself in the water.
Jellyfish
Ctenophore
Deep Sea Spider Deep Sea Squid
The Deep Seafloor
Deep sea sea urchin
Deep sea cucumber
Deep sea seastar and sea spider
Chimaera
Tripod fish
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
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
DinoflagellatesTrinidad
dysphotic
100m
The Electromagnetic Radiation Spectrum
Only green and blue wavelengths pass through water -about 100 meters
Light Penetration
in the Ocean
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.
luciferaseLuciferin + O2 Oxyluciferin + light
(bacterial / symbiotic)Light emitting organ that can’t be controlledor turned on and off.
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
Examples of fish that have bacterial photophores:• Anglerfish (ceratioids)• Pinecone fish (Monocentrids)• Lantern eyes/flashlightfish (Anomalopids)• Ponyfishes/slipmouths (Leiognathids)• Ichthyococcus
Flashlight Fish
• Has a flap to cover its glowing qualities.
Cephalopod Photophore
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
• 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.
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.
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).
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.
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.
Photocytes
• Photocytes - Cells that produce light (i.e., the bioluminescence).
Reflectors• The primary reflectors are structures at the
back of a photophore that reflect light toward the exterior. These may be broad-band reflectors that reflect all light or narrow-band reflectors that selectively reflect specific colors. Light not reflected by the latter structure passes through it and is absorbed by chromatophores that usually surround the reflector. Secondary reflectors can be found in various regions near the distal parts of the photophore. These generally have a role in controlling the directionality of the emitted light.
Photogenic crystalloids
• Some photocytes have crystalline-like inclusions that are thought to be the actual site within the cell where light is produced.
Intrinsic photophores:1. Widely distributed, ex. Cookie cutter shark2. Numerous photophores 1000’s3. Make own luminescence4. Control output of light (on and off)5. http://www.youtube.com/watch?v=syISlRJTaw4
Control of Bioluminescence:They can control bioluminescent intensity by controlling blood supply to light organ (i.e., control the amt of O2 -- O2 decreases light intensity decreases)
Light control using a shield• Lid• Vascular control• Rotation of organ
• Reproductive advantage• Countershading • Escape and avoid predation• Species recognition• Feeding• In evolution
Malacosteus (dragonfish)
squids- looking for mates.
Some predators can lure prey by mimicking signals of prey. Other predators dangle a lure to attract prey.
mid-water squid releases a bioluminescent cloud to startle and confuse predators.
pterapods
Firefly squid
Deep sea gulper
Photophores on ventral surface
Deep sea viper fish & deep sea shrimp
Black Devil Angler Fish
lure
angler fish
Any Questions?