Mariana´s Trench Trench: A long, steep-sided valley on the ocean floor. Mariana´s Trench is located in the western Pacific Ocean (11"21' N, 142" 12' E) near Japan and is the deepest known location on earth
How deep is Marianas Trench? Average depths of the earth's oceans - the Arctic Ocean is 1,038m deep - the Indian Ocean is 3,872m deep - the Atlantic Ocean is 3,872m deep - the Pacific Ocean is 4,188m deep The deepest point in each of the earth's oceans: - the Arctic Ocean's Eurasian Basin at 5,450m deep - the Indian Ocean's Java Trench at 7,725m deep - the Atlantic Ocean's Puerto Rico Trench at 8,648m deep - the Pacific Ocean's Mariana Trench at 11,033m deep
Deep Oceans: An Environment <ul><li>No light can penetrate into the deep ocean. Bioluminescence is the only available light </li></ul><ul><li>Extremely high pressure at deep ocean depths </li></ul><ul><li>Constant temperature ~ 2-4 ° C </li></ul><ul><li>The temperature around Hydrothermal vents can be as high as 400 °C </li></ul>
Bioluminescence <ul><li>Latin Origin: bios + lumen </li></ul><ul><li>Production and emission of light by a living organism by a chemical reaction </li></ul><ul><li>90% of deep sea organisms produce bioluminescense </li></ul><ul><li>Also found in terrestrial organisms: fireflies, glow worms, fungi </li></ul>
<ul><li>Since there is no photosynthesis in the deep oceans animals rely on falling organic matter ( marine snow) for food </li></ul><ul><li>Fish often have very big, tubular eyes to help them see in minimal light </li></ul>Deep Ocean Creatures
<ul><li>Pelagic (open-water) and benthic (bottom-feeders) species </li></ul><ul><li>Bioluminescent protrusion of the spine acts as a lure for prey </li></ul><ul><li>Males of some species never grow bigger than 14cm while females can reach a size of 1.5m </li></ul><ul><li>Male lives as a parasite off the female </li></ul>Anglerfish
Sea Pigs <ul><li>Range in size from </li></ul><ul><li>10-15 cm </li></ul><ul><li>Benthic echinoderms found at depths over 1000 m </li></ul><ul><li>Eat organic matter found in the mud of the ocean floor </li></ul><ul><li>Use tube feet for locomotion </li></ul>
Giant Sea Spider <ul><li>Over 1,300 species ranging in sizes from 1mm – 90cm </li></ul><ul><li>Some species live at depths of 7000m </li></ul><ul><li>Benthic and Pelagic species </li></ul><ul><li>Carnivorous predators </li></ul><ul><li>or scavengers </li></ul>
Giant Squid <ul><li>Can reach lengths of 20 m (including tentacles) </li></ul><ul><li>Eyes are 30cm in diameter </li></ul><ul><li>Found at depths of 1000 m </li></ul><ul><li>Natural predator is the sperm whale </li></ul>
Questions <ul><li>Is the pressure higher or lower in the deep ocean (compared to sea-level)? </li></ul><ul><li>Are there any photosynthetic reactions in the deep oceans? </li></ul><ul><li>How do organisms produce light in deep oceans? </li></ul><ul><li>What is falling organic matter called in the deep sea? </li></ul><ul><li>What do you call animals that live in open water? And animals that live on the sea floor? </li></ul><ul><li>Explain how Anglerfish reproduce. </li></ul><ul><li>How do Sea Pigs move? </li></ul><ul><li>What do Sea Spiders eat? </li></ul><ul><li>What animal eats Giant Squids? </li></ul><ul><li>Write your thoughts on the Deep Ocean. </li></ul>
Blue Whale ( Balaenoptera musculus ) <ul><li>Mammals with remarkable adaptations which allow them to survive in the oceans </li></ul><ul><li>The blue whale can grow to 30 m long and can weigh as much as 1,36x10 5 kg. </li></ul><ul><li>Its heart is the size of a small car </li></ul><ul><li>Its tongue is the size of an elephant </li></ul><ul><li>Groups of whales are called pods </li></ul><ul><li>Largest known animal in the history of the Earth </li></ul>Cetacea (Whales, Dolphins and Porpoises)
Whale Classification Whales belong to the order of Cetacea , so they are called Cetaceans . (Animalia-Chordata-Mammalia- Cetacea ). Cetaceans can be divided into two groups: Toothed Whales and Baleen Whales. Baleen Whales: larger whales that use a baleen to sieve tiny organisms from the water. They have two blowholes used for respiration. Toothed Whales: smaller whales that use teeth to catch and eat prey. They only have one blowhole since the second blowhole has evolved into an organ used for echolocation.
How does a whale breathe? The whale´s “nose” which is called the blowhole is located on the dorsal surface of the whale. Whales breathe by partially surfacing. At the surface they flex a muscle to open the blowhole and once they have inhaled the muscle relaxes to close the blowhole so that whale can submerge again. Because whales must partially surface to breathe, they have developed conscious breathing. A whale´s blowhole is unique to each species. Experienced whale watchers can identify a whale by it´s blowhole. Whales do not expel water from their blowhole. When the whale surfaces it expels air (water vapour) and since the air in their lungs is at a higher temperature than the external air, the water vapours in the expelled air quickly condense into a liquid.
Respiratory Adaptations <ul><li>Whales absorb 90% of the oxygen they inhale (humans only absorb 15%) </li></ul><ul><li>Whales have more myoglobin ; a protein that stores oxygen in muscles. The darker the muscle, the more myoglobin </li></ul><ul><li>When the whale submerges they lower their heartrate and their blood vessels constrict to use oxygen more efficiently without compromising blood pressure </li></ul><ul><li>( blood flow = pressure/resistance) </li></ul><ul><li>A sperm whale can hold it´s breath for 80-90 minutes </li></ul>
Temperature Adaptations <ul><li>Whales live in oceans where the water temperature hovers around freezing. To tolerate these cold temperatures whales have a thick layer of blubber all around their bodies. </li></ul><ul><li>Whale blubber acts as an insulator and also stores energy </li></ul><ul><li>Whale blubber does not compress under pressure </li></ul><ul><li>Whale blubber is consumed by Inuit people and is rich in nutrients and vitamines . </li></ul>
Pressure Adaptations Sprem whales can dive to 1000m deep (and deeper!). At this depth, over 90,000 kg of water is weighing down on every square inch of the whale´s body. At this pressure a human´s lungs would collapse . Whales have collapsable lungs that allow them to tolerate this enormous pressure.
Do whales dream? <ul><li>No breathing reflex (like in other mammals) </li></ul><ul><li>Whales sleep by resting half of their brain at a time . They are in a state of semi-consciousness . So far, whales have not been found to undergo REM (rapid eye movement) sleep </li></ul><ul><li>Whales can sleep horizontally or vertically and may swim slowly at the surface (logging) or motionless below the surface </li></ul>
Whale Fall: Life After Death When a whale dies and sinks to the bottom it is called a whale fall . Whale falls can support entire ecosystems for 50 to 75 years! which is the same amount of time a whale may live. Stage 1: Mobile scavenger stage - at this stage fish and crustaceans remove 90 % of the tissue - can last from months to years Stage 2: Enrichment opportunist stage - marine worms and crustaceans live off of the bones - Osedax worms (zombie worms) consume lipids inside the whale bones - can last for several years Stage 3: Sulphophilic stage - bacteria decompose the whale bones and produce hydrogen sulfide (H 2 S) which nourishes chemoautotrophic bacteria - this is the longest stage and can last for many years
Questions 1. What do you call a group of whales? 2. What is the scientific name for whales? 3. What are the two divisions of whales? What makes them different from each other? 4. Explain how whales breathe. 5. How do whales maintain a constant blood pressure when diving? 6. How do whales maintain a constant body temperature when diving? 7. How have whales adapted to the increased pressure underwater? 8. How do whales sleep? 9. What are the 3 stages of a whale fall? 10. What does chemoautotrophic mean?
Coral Coral is a living organism. It is an invertebrae and they are related to jellyfish and anenomes. (Animalia – Cnidaria – Anthozoa) . We can further divide corals into two subclasses. There are about 2,500 species of corals.
Two types of Corals Zoantharia corals have tentacles in multiples of 6 and form coral reefs. They use sediment and other substrate to form a hard body. They can be solitary or colonial. Alcyonaria corals have tentacles in multiples of 8. Most are colonial .
Coral Anatomy <ul><li>Soft bodied </li></ul><ul><li>Carnivorous </li></ul><ul><li>Stinging tentacles arranged in a circle around the mouth </li></ul><ul><li>Body symmetry </li></ul><ul><li>Specialized tissues </li></ul><ul><li>Nervous system but no brain </li></ul><ul><li>Two life stages: polyp and medusa </li></ul>
How does a coral eat? <ul><li>Corals have a specialized stinging cell called a nematocyst </li></ul><ul><li>When the nematocyst is stimulated it releases a sharp barb </li></ul><ul><li>The barb fires out and catches the food and brings it towards the mouth where it is broken down in the stomach </li></ul><ul><li>The food is digested intracellulary </li></ul>
Video of nemotocytes in action http://www.youtube.com/watch?v=RYVHK2vM1_Y&feature=related
Coral Habitat Corals are found in all of the world´s oceans. However, we only find coral reefs in tropical oceans. Corals can be found at depths of 6000m but coral reefs are only found at maximum depths of 45m (where there is sunlight).
Coral Reef Environment <ul><li>Coral reefs need: </li></ul><ul><li>Sunlight (symbiotic algae) </li></ul><ul><li>Warm temperatures (20 º C – 28 º C) </li></ul><ul><li>High salinity </li></ul><ul><li>Low carbon dioxide </li></ul><ul><li>Mildly turbulent waters (waves) </li></ul><ul><li>Substrate; so that the corals can anchor themselves </li></ul>
Types of Coral Reefs There are 3 types of coral reefs: Fringing : these reefs grow close to the shore Barrier: these reefs grow close to the shore but they have a lagoon that seperates it from the shore Atoll: a ring of coral that grows on a submerged volcano or mountain
Why are coral reefs so important? Marine Rainforests: coral reefs provide a habitat for many organisms.They are a biological hotspot , a place where biodiversity is very high! Coastline protection: Coral reefs surround coastlines and protect the shore from erosion Irreplaceable: Corals grow very slowly, about 1cm a year! If they are destroyed it will take 1000s of years for them to grow back.
Coral reefs in danger! Ocean pollution in the form of oil slicks , pesticide and chemical runoff and garbage are very harmful for corals. Pesticide runoff can increase the concentration of nutrients in the oceans, this increases algae populations which can smother corals. Deforestation causes erosion, which can bury corals and prevent the sunlight from entering the shallow waters. Since Coral reefs are dependent on symbiotic relationship with algae, if there is no sunlight there are no coral reefs.
Over fishing and Ocean Trawling . Ocean trawling is a very destructive method of fishing. Big ships use machinery that completely destroys coral reefs. Coral reefs in danger!
Video of ocean trawling http://www.youtube.com/watch?v=1Q7acR8-ZFU
Global Warming. Since corals are very sensitive to temperature changes, even a slight increase in ocean temperatures could be devastating. High concentrations of CO 2 increase the oceans´ acidity. In an acidic environment corals are not able to produce their hard skeletons which build the reef. When corals are dying they become white, this is called coral bleaching . Coral reefs in danger!