The uppermost layer of the world's oceans is bathed in sunlight during the daytime. photic zone, euphotic zone (euphotic means "well lit" in Greek) or the epipelagic zone (epipelagic means "upon the sea"). The depth of this zone depends on the clarity or murkiness of the water.

Photosynthetic organisms live in this zone and food is abundant. Photosynthesis in the oceans creates approximately 90% of the Earth's gaseous oxygen. produced by phytoplankton. primary producers (autotrophs) The sea surface temperatures range from as 97°F (36°C) in the Persian Gulf to 28°F (-2°C) near the north pole.

Primary producers – phytoplankton, green red and brown algae, and kelp Primary consumers – zooplankton, small fish Secondary consumers – larger fish, baleen whales, jellyfish, marine mammals Top of the food chain – killer whales, dolphins, sharks

Stay within a physically tolerable zone Find enough food to eat and grow Find mate(s) and successfully reproduce Avoid being eaten

Noctiluca (Sea Sparkle) large buoyant vacuoles Cranchiid (Glass squid) * large fluid-filled chamber filled with an ammonia solution Janthina (violet snail) mucous bubbles Fish - swim bladder Flat surfaces or bodies with appendages do not slip as easily through the water

Pectoral fins reduce sinking. allows organisms to go deep and then return to surface

Build a collection device or filter BE BIG! You can eat almost anything you encounter Can swim across “ocean deserts” to find food High storage capacity (longer between meals but need more food/unit time) Hunt in groups Orcas can even hunt much larger whales

Stay with your food - Seabirds follow schools of fish Know where your food will be Hunt in areas with specific properties (e.g. upwelling regions or inside gyres) likely to retain or attract prey Cue in on timed migration of prey

Broadcast spawning Release of millions of eggs & sperm increases chance that sperm & egg will meet Ex. oysters, coral Stay together schooling fish, social marine mammals & deep sea angler fish

Meet at a predetermined location If separated or too costly to stay together (e.g. competition for food), meet at a specific time & place Ex. Colonial sea birds and Pacific salmon Be clonal Asexual reproduction - no mate needed!

Defend yourself Mechanical Spines Tough skin Chemical Taste bad Make predators sick

BE BIG! Big things have fewer predators, especially in the marine environment Be Cryptic Be transparent Be reflective Be camouflaged Be countershaded

when an animal is light on its underside and dark on its upper parts. When a predator looks down at a countershaded animal, it blends into the darker waters; when a predator looks at a countershaded animal from below, the light underbelly disappears into the light.

Regions of the deep ocean Epipelagic Mesopelagic Bathypelagic Abyssopelagic Hadalpelagic 200m 1000m 4000m 6000m The Trenches The Midnight Zone The Twilight Zone The Abyss

The physical characteristics that deep sea life must contend with to survive are: abiotic (non-living) ones, namely light (or lack thereof), pressure, currents, temperature, oxygen, nutrients and other chemicals; and biotic ones, that is, other organisms that may be potential predators, food, mates, competitors or symbionts. All these factors have led to fascinating adaptions of deep sea life for sensing, feeding, reproducing, moving, and avoiding being eaten by predators.

Pressure For every 10m (33ft) pressure increases by 1atm (14.7 pounds per square foot) Lack of Food 5% of food made at surface makes its way to deep regions Deep sea fish do not migrate Oxygen Minimum Layer: about 500m Oxygen enters ocean by: gas exchange with atmosphere, by-product of photosynthesis Respiration uses up O 2 O 2 can drop to practically nothing

The only light is produced by bioluminescence, a chemical reaction in the creature's body that creates a low level light. Some produce red light to lure curious prey. Sometimes used to signal potential mates with a specific light pattern. Fish here are often transparent, black, silvery and even red in color. The absence of red light at these depths being red makes them invisible. Large eyes to capture what little light exists. Often equipped with a powerful sense of smell – to find food and mates.

Deep sea anglerfish –reproductive adaptation. Males are tiny in comparison to females and attach themselves to their mate using hooked teeth establishing a parasitic relationship for life. The blood vessels of the male merges with the female's so that he receives nourishment from her. In exchange, the female is provided with a very reliable sperm source.

Deep sea creatures have adapted to pressure by developing bodies with no excess cavities, such as swim bladders, that would collapse under intense pressure. The flesh and bones of deep sea marine creatures are soft and flabby.

Corpses of large animals that sink to the bottom provide infrequent feasts for deep sea animals. Large and expandable stomachs to hold large quantities of food. Don't expend energy swimming in search of food, rather they remain in one place and ambush their prey Large jaws ensure that any prey captured has little chance of escape.

Deep Sea Creatures Video Deep Sea Creatures Pictures

Students will design their own well-adapted species. Some of the things you need to think about are how the organism: collects food, finds a mate, avoids being eaten, and stays afloat. Sketch, color, and describe the organism you designed. EXTRA CREDIT FOR ADDITIONAL DEEP WATER ADAPTATIONS Create-a-Creature: Megasaurus Finds a MateStays Afloat1)2) Collects FoodAvoids being Eaten1)2)