Deep Sea Hydrothermal Vent Communities

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Transcript 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
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
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
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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. (1,0008,000 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=&esr
c=s&source=images&cd=&cad=rja&uact=8&ved
=0CAYQjB0&url=http%3A%2F%2Fanimalkid.com%2Flanternfish.html&ei=AF3VPDlMYi4ggT_2IPgBQ&bvm=bv.87611401,d.eX
Y&psig=AFQjCNF_5F_qKHI6gLrB5mnGjmAYK51
52g&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=9HXXQBz6
Vv0
Seeing in the Dark
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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 spineacts 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%2F
april22%2Fmedia%2Furchins.html&ei=nfAAVd76LcOdgwSO_oKADQ&bvm=bv.87920726,d.eXY&
psig=AFQjCNGiKwq3L2guBI1jfZGaALmQZYxeuA&ust=1426211342851320
http://www.schmidtocean.org/story/show/13
94
Giant Squid
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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/sq
uid-vampire-threatened-vin
http://www.amazingandweird.com/facts/vam
pire-squid-facts-20-facts-about-vampire-squid/
Life on the BottomBenthic Communities
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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
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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
Fallout of precipitated MnO2
and FeO(OH)
Precipitation of FeS,
CaSO4, CuFeS2
Basalt
• 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 Worms
Riftia worm
Size: up to 6 ft- 10 ft.
Thought they were clams
Red plume acts like gillexchanges 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.
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
Deep sea Lizardfish
Dragonfish
Hairy Anglerfish
Gulper Eel
Anglerfish
Anglerfish
Pearleye Fish
Dragonfish
Redmouth Whalefish
Lancetfish
Hatchetfish
Vulcan
Octopus
Flashlight
Fish
Dragonfish
Sea Pig
Cusk Eel
Deep Sea Lobster
Uses density
and pressure
differences to
suspend itself
in the water.
Giant Sea Spider
Greenland Sleeper Shark
Ctenophore
Jellyfish
Deep Sea Spider
Deep Sea Squid
The Deep Seafloor
Deep sea sea urchin
Deep sea seastar
and sea spider
Deep sea cucumber
Tripod fish
Chimaera
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
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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/d
eep-sea-creatures/#/deep-sea05-six-gillshark_18165_600x450.jpg
• http://www.discovery.com/tvshows/curiosity/videos/first-video-of-a-giantsquid.htm
Dinoflagellates
Trinidad
100m
dysphotic
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.
luciferase
Luciferin + O2
Oxyluciferin + light
(bacterial / symbiotic)
Light emitting organ that can’t be controlled
or 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=BtQGslJ
jLdc
• 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/reflec
tion 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 shark
2. Numerous photophores 1000’s
3. Make own luminescence
4. 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
Photophores on ventral
surface
Deep sea gulper
Deep sea viper fish & deep sea shrimp
Black Devil Angler Fish
lure
angler fish