Life in the Ocean. 2 Marine Biology The tremendous variety of marine organisms that inhabit the...

Life in the OceanLife in the Ocean

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Marine BiologyMarine Biology

The tremendous variety of marine The tremendous variety of marine organisms that inhabit the diverse oceanic organisms that inhabit the diverse oceanic environment are classified into groups to environment are classified into groups to simplify identification and illustrate simplify identification and illustrate similarities and differences between them.similarities and differences between them.

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Marine LifeMarine Life

Marine organisms are divided into the Marine organisms are divided into the following three groups based on their life following three groups based on their life styles and habitat:styles and habitat:– a.a. planktonplankton that float or drift with the that float or drift with the

currents and includes both animals and plantscurrents and includes both animals and plants– b.b. nektonnekton that are able to swim freely and that are able to swim freely and

includes only animals includes only animals – c.c. benthosbenthos that live attached to, on, or in that live attached to, on, or in

the bottom substrate of the sea floor and may the bottom substrate of the sea floor and may include plants and animals include plants and animals

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Radiolarians- Plankton

Nekton- Fish

Benthos- Starfish

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TaxonomyTaxonomy

The scientific classification of organisms is The scientific classification of organisms is known as taxonomy.known as taxonomy.More than 200 years ago Carolus Linnaeus More than 200 years ago Carolus Linnaeus proposed the first classification scheme that proposed the first classification scheme that divided organisms into two kingdoms, plants and divided organisms into two kingdoms, plants and animals.animals.The Linnean system has since developed into a The Linnean system has since developed into a five-kingdom system that is the most widely five-kingdom system that is the most widely used classification system today. used classification system today. The five kingdoms in this system are: Monera The five kingdoms in this system are: Monera (single-celled organisms without a membrane-(single-celled organisms without a membrane-bound nucleus), Protista, Fungi, Plantae, and bound nucleus), Protista, Fungi, Plantae, and Animalia.Animalia.

Taxonomic Classification

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TaxonomyTaxonomy

A new system that is based on genetic and A new system that is based on genetic and biochemical research defines three biochemical research defines three domains domains above the kingdom level:above the kingdom level:– a.a. Bacteria ,Bacteria ,– b.b. Archaea, andArchaea, and– c.c. Eukarya (all nuclei-containing organisms) Eukarya (all nuclei-containing organisms)

Members of the Monera Kingdom are placed in Members of the Monera Kingdom are placed in either the Bacteria domain or the Archaea either the Bacteria domain or the Archaea domain. The Eukarya domain includes all other domain. The Eukarya domain includes all other Kingdoms.Kingdoms.Classification schemes for living organisms are Classification schemes for living organisms are always subject to modification as new always subject to modification as new discoveries are made.discoveries are made.

Energy and Marine Life

• Photosynthesis– Light trapped by chlorophyll in producers

and changed into chemical energy

– CO2 +H2O +Light (Chlorophyll)-> C6H12O6+6O2

– Carbon dioxide + water +light -> glucose + 6 molecules of oxygen

• Chemosynthesis– Production of energy by bacteria particularly

in deep sea vents from sulfide rich molecules

Plankton Nets

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NutrientsNutrients

The sea's plant life requires nutrients to The sea's plant life requires nutrients to survive and the lack of any essential survive and the lack of any essential nutrient will adversely affect plant nutrient will adversely affect plant productivityproductivity

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NutrientsNutrients

Two nutrients that act as fertilizers for the Two nutrients that act as fertilizers for the ocean's plants are nitrate (NOocean's plants are nitrate (NO33

--) and ) and phosphate (POphosphate (PO44

-3-3).).

Nutrients are removed from surface waters Nutrients are removed from surface waters and incorporated into plant tissue during and incorporated into plant tissue during photosynthesis.photosynthesis.These nutrients are returned to the water These nutrients are returned to the water either through the expelling of waste either through the expelling of waste products or at depth as a result of the products or at depth as a result of the decay of organic material.decay of organic material.

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NutrientsNutrients

Nutrients that are released at depth are brought back to Nutrients that are released at depth are brought back to the surface in zones of upwelling. the surface in zones of upwelling. These regions typically have very high levels of These regions typically have very high levels of productivity because of the nutrient rich waters. productivity because of the nutrient rich waters. In addition, these upward moving waters are often cold In addition, these upward moving waters are often cold and therefore rich in important dissolved gases as well.and therefore rich in important dissolved gases as well.Diatoms require dissolved silica to form their rigid outer Diatoms require dissolved silica to form their rigid outer coverings.coverings.Iron, manganese, and zinc are required in some Iron, manganese, and zinc are required in some physiological systems.physiological systems.Zinc and copper are required in some enzyme systems Zinc and copper are required in some enzyme systems

Trophic Relationships

• Autotrophs– Primary producers– Photosynthetic or chemosynthetic organisms

• Heterotrophs– Consumers– Primary– Secondary– Top consumers– Each level of the trophic pyramid is 1/10th of the level

below it

Food Web

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ZonationZonation

In the vast oceanic environment, both the In the vast oceanic environment, both the water and the sea floor are divided into water and the sea floor are divided into specific zones that have distinct specific zones that have distinct characteristics and support different characteristics and support different populations of organismspopulations of organisms

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ZonationZonationThe two major zones in the marine environment The two major zones in the marine environment are the are the – pelagic zone, which is the water, pelagic zone, which is the water, – benthic zone, which is the sea floor. benthic zone, which is the sea floor. – Each of these is further subdivided into a number of Each of these is further subdivided into a number of

smaller zones.smaller zones.

The pelagic zone consists of two subdivisions; The pelagic zone consists of two subdivisions; – the neritic zone (water lying above the continental the neritic zone (water lying above the continental

shelf), shelf), – the oceanic zone (the main body of water that lies off the oceanic zone (the main body of water that lies off

the continental shelf). the continental shelf). – The oceanic zone is vastly larger that the neritic. The oceanic zone is vastly larger that the neritic. – The relatively small neritic zone is distinguished from The relatively small neritic zone is distinguished from

the rest of the water realm because of the the rest of the water realm because of the tremendous variations found in this shallow tremendous variations found in this shallow environment.environment.

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The oceanic zone The oceanic zone

ZoneZone Depth Range (m)Depth Range (m) Depth Range (ft)Depth Range (ft)

epipelagicepipelagic 0 - 2000 - 200 0 - 6600 - 660

mesopelagicmesopelagic 200 - 1000200 - 1000 660 - 3300660 - 3300

bathypelagicbathypelagic 1000 - 40001000 - 4000 3300 - 13,2003300 - 13,200

abyssopelagicabyssopelagic 4000 - 4000 - 13,200>13,200>

All oceanic zones with the exception of the All oceanic zones with the exception of the epipelagic are aphotic. epipelagic are aphotic.

The epipelagic and neritic zones coincide roughly in The epipelagic and neritic zones coincide roughly in depth and are both in the photic region of the water.depth and are both in the photic region of the water.

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The benthic zone The benthic zone ZoneZone Depth Range (m)Depth Range (m)supralittoral (splash)supralittoral (splash) area just above the high area just above the high

water mark, where wave spray can water mark, where wave spray can reachreach

littoral (intertidal)littoral (intertidal) area between low and high tidearea between low and high tidesublittoral (subtidal)sublittoral (subtidal) the rest of the continental the rest of the continental

shelf below low tide levelshelf below low tide levelbathyalbathyal 200 - 4000 (660 - 13,200 ft)200 - 4000 (660 - 13,200 ft)abyssalabyssal 4000 - 6000 (13,200 - 19,800 ft)4000 - 6000 (13,200 - 19,800 ft)hadalhadal 6000 - deepest depths ( greater than 6000 - deepest depths ( greater than

19,800 ft)19,800 ft)

The properties of the littoral and epipelagic zones depend on latitude and The properties of the littoral and epipelagic zones depend on latitude and time, ranging from tidal periods to annual cycles, since they are so shallow.time, ranging from tidal periods to annual cycles, since they are so shallow.The hadal zone shows no seasonal change and is associated with the The hadal zone shows no seasonal change and is associated with the ocean’s trenches and deeps.ocean’s trenches and deeps.

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Buoyancy, Flotation & ViscosityBuoyancy, Flotation & Viscosity

Organisms that live on land are Organisms that live on land are surrounded by the low-density surrounded by the low-density atmosphere, and hence, must expend a lot atmosphere, and hence, must expend a lot of energy in supporting themselves. of energy in supporting themselves. Marine organisms are surrounded by Marine organisms are surrounded by seawater, which has a density close to seawater, which has a density close to their own and provides some of the their own and provides some of the necessary support. necessary support. Special adaptations by many organisms Special adaptations by many organisms provide additional support.provide additional support.

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The support that seawater provides for marine The support that seawater provides for marine organisms is called buoyancy. organisms is called buoyancy. Buoyancy helps keep floating organisms near Buoyancy helps keep floating organisms near the surface, reduces the amount of energy used the surface, reduces the amount of energy used by swimming organisms, and helps support by swimming organisms, and helps support bottom-dwelling organisms.bottom-dwelling organisms.In addition to the buoyancy of seawater, many In addition to the buoyancy of seawater, many organisms have developed special mechanisms organisms have developed special mechanisms that allow them to easily maintain a preferred that allow them to easily maintain a preferred depth in the water.depth in the water.

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A wide variety of organisms have the ability to A wide variety of organisms have the ability to secrete and store gas in their bodies to lower secrete and store gas in their bodies to lower their overall density and increase their flotation. their overall density and increase their flotation. These include:These include:– a.a. some jellyfish-type organisms such as the some jellyfish-type organisms such as the

Portuguese man-of-war and the by-the-Portuguese man-of-war and the by-the-wind wind sailor,sailor,

– b.b. some varieties of algae,some varieties of algae,– c.c. floating snails,floating snails,– d.d. the chambered nautilus,the chambered nautilus,– e.e. the cuttlefish (a relative of the squid), andthe cuttlefish (a relative of the squid), and– f.f. fish with swim bladders.fish with swim bladders.

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Salinity and OsmosisSalinity and Osmosis

The body fluids of marine organisms are separated from The body fluids of marine organisms are separated from seawater by semipermeable membranes (cell walls) that seawater by semipermeable membranes (cell walls) that allow the passage of water molecules but inhibit the allow the passage of water molecules but inhibit the passage of salts.passage of salts.Most fish have body fluids with lower salt concentrations Most fish have body fluids with lower salt concentrations than seawater, thus water molecules tend to move from than seawater, thus water molecules tend to move from the organisms to the seawater by osmosis.the organisms to the seawater by osmosis.To prevent dehydration, fish must constantly work to To prevent dehydration, fish must constantly work to expel salt from their tissues and increase the expel salt from their tissues and increase the concentration of water molecules. concentration of water molecules. They do this by drinking large volumes of seawater and They do this by drinking large volumes of seawater and expelling the salt through their gills.expelling the salt through their gills.Some organisms, like sharks and rays, have body fluids Some organisms, like sharks and rays, have body fluids that have salt concentrations nearly equal to that of that have salt concentrations nearly equal to that of seawater so they are not faced with this problem.seawater so they are not faced with this problem.

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TemperatureTemperature

Temperature variations in seawater have Temperature variations in seawater have an effect on marine life in two ways. an effect on marine life in two ways. – Changes in temperature result in density Changes in temperature result in density

changes in the water that affect buoyancy, changes in the water that affect buoyancy, – temperature plays a role in determining the temperature plays a role in determining the

metabolic rates of cold-blooded organismsmetabolic rates of cold-blooded organisms

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A decrease in temperature results in an increase A decrease in temperature results in an increase in the density of seawater and the buoyancy it in the density of seawater and the buoyancy it provides for marine organisms. provides for marine organisms. In general, microscopic organisms that inhabit In general, microscopic organisms that inhabit warm water develop spines and ornate warm water develop spines and ornate appendages, have larger surface areas, and appendages, have larger surface areas, and more frequently produce gas bubbles to more frequently produce gas bubbles to increase their flotation, increase their flotation, those that inhabit cold, more viscous water can those that inhabit cold, more viscous water can retain smoother profiles and still have little retain smoother profiles and still have little trouble remaining near the surface.trouble remaining near the surface.

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Other than the birds and mammals (and some large Other than the birds and mammals (and some large fishes), marine organisms are cold-blooded and their fishes), marine organisms are cold-blooded and their body temperatures will vary with changes in their body temperatures will vary with changes in their environment. environment. These organisms are ectotherms. These organisms are ectotherms. In cold water, metabolic rates will usually be lower and In cold water, metabolic rates will usually be lower and growth rates of organisms will be slower, although they growth rates of organisms will be slower, although they can attain larger sizes. can attain larger sizes. The opposite will be true in warm water.The opposite will be true in warm water.Warm-blooded organisms such as birds and mammals Warm-blooded organisms such as birds and mammals are less restricted by temperature changes and their are less restricted by temperature changes and their natural habitats cover broader regions. natural habitats cover broader regions. These organisms are endotherms. These organisms are endotherms. An excellent example of this is the annual migration of An excellent example of this is the annual migration of whales between polar and tropical waters.whales between polar and tropical waters.

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PressurePressure

The change in pressure with depth in The change in pressure with depth in the seas is so great that organisms the seas is so great that organisms must adapt in special ways to survive.must adapt in special ways to survive.The greatest effect that increasing pressure with The greatest effect that increasing pressure with depth has on marine organisms is in the depth has on marine organisms is in the compression of gas-filled cavities or lungs.compression of gas-filled cavities or lungs.Deep-dwelling organisms such as worms, Deep-dwelling organisms such as worms, crustaceans, and sea cucumbers, are not crustaceans, and sea cucumbers, are not affected by pressure because they do not have affected by pressure because they do not have gas-filled cavities or lungs.gas-filled cavities or lungs.

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PressurePressure

Deep-diving marine organisms often have a very high Deep-diving marine organisms often have a very high oxygen capacity for their body weight. oxygen capacity for their body weight. Weddell seals have an oxygen capacity of 87 mL/kg and Weddell seals have an oxygen capacity of 87 mL/kg and penguins have an oxygen capacity of 55mL/kg. Both of penguins have an oxygen capacity of 55mL/kg. Both of these are much higher than human oxygen capacity of these are much higher than human oxygen capacity of about 20 mL/kg.about 20 mL/kg.Sperm whales can dive to depths exceeding 2000 m Sperm whales can dive to depths exceeding 2000 m (6600 ft) in search of food. (6600 ft) in search of food. Human divers deal with the increased pressure either by Human divers deal with the increased pressure either by descending in a rigid pressure suit or by breathing gases descending in a rigid pressure suit or by breathing gases under the same pressure as the environment. under the same pressure as the environment. Air breathed under pressure for extended periods can Air breathed under pressure for extended periods can cause the buildup of nitrogen in the blood and tissues. cause the buildup of nitrogen in the blood and tissues. Rapid ascent may produce nitrogen bubbles in the blood Rapid ascent may produce nitrogen bubbles in the blood and tissues, causing the bends, a condition that can be and tissues, causing the bends, a condition that can be crippling and even fatal.crippling and even fatal.

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GasesGases

life in the marine realm requires carbon dioxide life in the marine realm requires carbon dioxide and oxygen.and oxygen. Carbon dioxide enters the water through Carbon dioxide enters the water through exchange with the atmosphere, production by exchange with the atmosphere, production by respiration, and the decay of organic material. respiration, and the decay of organic material. It is required by plants for photosynthesis.It is required by plants for photosynthesis.There is no shortage of carbon dioxide in There is no shortage of carbon dioxide in seawater so it is not a limiting factor for plant seawater so it is not a limiting factor for plant productivity.productivity.Carbon dioxide also plays a critical role in Carbon dioxide also plays a critical role in buffering the pH of seawater, thus making it a buffering the pH of seawater, thus making it a stable environment for life.stable environment for life.

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GasesGases

Oxygen enters the oceans at or near the sea surface by direct Oxygen enters the oceans at or near the sea surface by direct exchange with the atmosphere and production in photosynthesis. exchange with the atmosphere and production in photosynthesis. The availability of oxygen at depth depends on vertical mixing to The availability of oxygen at depth depends on vertical mixing to bring it from the surface.bring it from the surface.The saturation value of oxygen in seawater is a function of the The saturation value of oxygen in seawater is a function of the water's temperature, salinity, and pressure. water's temperature, salinity, and pressure. The solubility of oxygen increases as the temperature and salinity The solubility of oxygen increases as the temperature and salinity decrease and as the pressure increases.decrease and as the pressure increases.On warm, quiet days, the temperature and salinity of water in On warm, quiet days, the temperature and salinity of water in shallow pools and bays can increase, thus decreasing the water’s shallow pools and bays can increase, thus decreasing the water’s ability to hold oxygen.ability to hold oxygen.Organisms living in shallow coastal waters where the oxygen Organisms living in shallow coastal waters where the oxygen concentration in the water can drop in response to environmental concentration in the water can drop in response to environmental conditions can be easily driven out into deeper water where conditions can be easily driven out into deeper water where conditions are more uniform.conditions are more uniform.Only anaerobic, or non-oxygen-requiring, bacteria may populate Only anaerobic, or non-oxygen-requiring, bacteria may populate deep, isolated basins with little or no dissolved oxygen in the water.deep, isolated basins with little or no dissolved oxygen in the water.

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LightLight

The oceans can be divided vertically into The oceans can be divided vertically into two layers, two layers,

an upper photic zone, where sufficient an upper photic zone, where sufficient sunlight penetrates to support sunlight penetrates to support photosynthesisphotosynthesis

lower aphotic zone, where the intensity of lower aphotic zone, where the intensity of sunlight is too low or doesn't penetrate at sunlight is too low or doesn't penetrate at all, so there is no photosynthetic activity.all, so there is no photosynthetic activity.

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LightLight

Water is semi-transparent to sunlight; sunlight will pass Water is semi-transparent to sunlight; sunlight will pass through water and gradually be absorbed and scattered through water and gradually be absorbed and scattered until, at some depth, there is total darkness.until, at some depth, there is total darkness.The depth of the photic zone at any given location The depth of the photic zone at any given location depends on how rapidly light is absorbed and scattered depends on how rapidly light is absorbed and scattered at that spot. at that spot. This can change with varying sea surface conditions, This can change with varying sea surface conditions, time of day, and the seasons.time of day, and the seasons.Sunlight will penetrate to greater depths if the sun's rays Sunlight will penetrate to greater depths if the sun's rays are more nearly perpendicular to the water's surface, if are more nearly perpendicular to the water's surface, if there is less suspended particulate matter in the water, there is less suspended particulate matter in the water, and if the light is closer to the blue-green wavelengths of and if the light is closer to the blue-green wavelengths of the spectrum.the spectrum.

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Mesopelagic ZoneMesopelagic Zone

OML (Oxygen Minimum Layer ) occursOML (Oxygen Minimum Layer ) occursat a depth of 700 to 1000mat a depth of 700 to 1000mIntermediate water masses move through Intermediate water masses move through this zonethis zoneContains highest levels of nutrientsContains highest levels of nutrientsExtremely dim sunlight; inhabited byExtremely dim sunlight; inhabited byfish with very large and sensitive eyesfish with very large and sensitive eyesand other bioluminescent organismsand other bioluminescent organisms

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Bioluminescence Bioluminescence

Bioluminescence is produced by a chemical interaction Bioluminescence is produced by a chemical interaction between the compound, luciferin, and the enzyme, between the compound, luciferin, and the enzyme, luciferase. luciferase. It is the same process we more often see in fireflies or It is the same process we more often see in fireflies or glowing fungus on land.glowing fungus on land.Bioluminescence produces light with a 99% efficiency.Bioluminescence produces light with a 99% efficiency.A wide variety of organisms are bioluminescent, A wide variety of organisms are bioluminescent, including microscopic organisms in shallow water, squid, including microscopic organisms in shallow water, squid, shrimp, and some varieties of fish.shrimp, and some varieties of fish.Bioluminescence of plankton is triggered by agitation in Bioluminescence of plankton is triggered by agitation in the water that disturbs the organisms. the water that disturbs the organisms. The wake of a boat will often glow at night with The wake of a boat will often glow at night with bioluminescence.bioluminescence.

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BioluminescenceBioluminescence

Light produced by a chemical reaction which Light produced by a chemical reaction which originates in an organism. originates in an organism. – The one which produces the light is generically The one which produces the light is generically

called a "called a "luciferinluciferin" and the one that drives or " and the one that drives or catalyzes the reaction is called a "catalyzes the reaction is called a "luciferaseluciferase." ."

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BioluminescenceBioluminescence

Some mid-depth and deep-water fish have Some mid-depth and deep-water fish have organs called photophores that produce visible organs called photophores that produce visible light that can be used for identification or light that can be used for identification or communication, to lure prey or confuse communication, to lure prey or confuse predators, or to help the fish see in total predators, or to help the fish see in total darkness.darkness.Other fish have photophores on their ventral Other fish have photophores on their ventral (lower) surface, making them more difficult to (lower) surface, making them more difficult to see from below when viewed against the lighter see from below when viewed against the lighter surface water.surface water.Some fish have photophores below their jaws or Some fish have photophores below their jaws or on the end of flexible dorsal spines that act as on the end of flexible dorsal spines that act as lures for prey.lures for prey.

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The blackdevil angler fish, Melanocetus johnsonii, has a luminescent lure that she uses to attract prey and to identify herself to potential mates

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ColorColor

Marine organisms use color to their Marine organisms use color to their advantage in many different ways. advantage in many different ways.

Color is definitely used to enhance survival Color is definitely used to enhance survival through camouflage and as a warning to through camouflage and as a warning to predators. predators.

It is probably used in other ways as well It is probably used in other ways as well that will be discovered through additional that will be discovered through additional study.study.

Figure 13.10

Countershading

Dark

Light

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Bottom EnvironmentsBottom Environments

Organisms that live on the sea floor must Organisms that live on the sea floor must adapt to different types of bottom.adapt to different types of bottom.

The bottom on which an organism lives is The bottom on which an organism lives is called the substrate.called the substrate.

Examples of different substrate include Examples of different substrate include rock, mud, sand, or gravel.rock, mud, sand, or gravel.

The substrate provides food, shelter, and a The substrate provides food, shelter, and a place of attachment.place of attachment.

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Banded Benthic Communities

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Organisms that live on, such as crabs, or Organisms that live on, such as crabs, or attached to, such as barnacles, the substrate attached to, such as barnacles, the substrate are called are called epifauna.epifauna.Organisms that burrow and live buried in the Organisms that burrow and live buried in the substrate, such as clams, are called substrate, such as clams, are called infauna.infauna.Substrates are most variable along shallow Substrates are most variable along shallow coastal areas. coastal areas. Here we can find rocks, gravel, sand bars, and Here we can find rocks, gravel, sand bars, and mud flats along the same strip of coast.mud flats along the same strip of coast.At increasing distance from the shore and depth At increasing distance from the shore and depth below the surface the substrate particles below the surface the substrate particles become smaller and eventually the substrate is become smaller and eventually the substrate is very homogeneous.very homogeneous.

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Sediment grain size is also important for bottom-dwelling Sediment grain size is also important for bottom-dwelling organisms. organisms. Seaweeds may require rocks or large cobbles for Seaweeds may require rocks or large cobbles for attachment while a burrowing worm would need fine-attachment while a burrowing worm would need fine-grained mud.grained mud.Infauna that derive some of their nourishment by Infauna that derive some of their nourishment by ingesting sediments are called ingesting sediments are called deposit feedersdeposit feeders. . The sediment typically includes some organic matter.The sediment typically includes some organic matter.Organisms attached to the sea floor often modify their Organisms attached to the sea floor often modify their habitat in ways that provide food, shelter, and additional habitat in ways that provide food, shelter, and additional surfaces for the attachment of additional organisms. surfaces for the attachment of additional organisms. Examples include seaweed forests, eel grass beds, and Examples include seaweed forests, eel grass beds, and coral reefs coral reefs

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Pelagic EnvironmentsPelagic Environments

The NektonThe Nekton– FishFish– Marine MammalsMarine Mammals

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The morphology of fish has The morphology of fish has evolved to allow them to move evolved to allow them to move

through the water easily.through the water easily.

The fish’s body must overcome three types of The fish’s body must overcome three types of drag (resistance): surface drag, form drag, drag (resistance): surface drag, form drag, and turbulent drag.and turbulent drag.

Aspect ratio is the ratio of the square of the Aspect ratio is the ratio of the square of the caudal fin height to caudal fin area: caudal fin height to caudal fin area: AR = (Caudal Fin Height)AR = (Caudal Fin Height)22/Caudal Fin Area/Caudal Fin Area

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Selective Adaptive Strategies

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Speed of a fish is dependent upon body Speed of a fish is dependent upon body length, beat frequency, and the aspect length, beat frequency, and the aspect ratio of the caudal fin.ratio of the caudal fin.

There are three basic modes of fish There are three basic modes of fish locomotion, each adapted to a different locomotion, each adapted to a different life style.life style.

There is a strong correlation between There is a strong correlation between predation success and mode of predation success and mode of locomotion.locomotion.

Selective Adaptive Strategies

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Marine Mammals: Order Marine Mammals: Order Cetacea Cetacea

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Toothed Whales

Dolphin Porpoise

Sperm WhaleNarwhal

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Gray Whale Blue Whale

RightWhale

HumpbackWhale

Baleen Whales

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FACTSFACTS

Blue Whale needs 1.5 million Cal/day for Blue Whale needs 1.5 million Cal/day for Basal metabolic rate (during fattening for Basal metabolic rate (during fattening for winter 3 million). 1 lb. of krill = 400 Cal, so 4 winter 3 million). 1 lb. of krill = 400 Cal, so 4 tons per day are needed. tons per day are needed. Gestation is as little as 10 months for some Gestation is as little as 10 months for some of the dolphins, up to 15 months for whales. of the dolphins, up to 15 months for whales. Born tail first, able to swim immediately. Born tail first, able to swim immediately. Most larger whales migrate poleward in the Most larger whales migrate poleward in the summer and toward the equator in winter, summer and toward the equator in winter, calving often in wintering grounds. calving often in wintering grounds.

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Order Carnivora (The Order Carnivora (The Pinnipeds)Pinnipeds)

3 Families: 3 Families:

Odobenidae (Walrus) Odobenidae (Walrus)

Otariidae (Eared Seals) Otariidae (Eared Seals)

Phocidae (True Seals) Phocidae (True Seals)

Varied diets among all the different Varied diets among all the different species. species.

Gestation is 10-12 months. Gestation is 10-12 months.

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Close RelationshipsClose Relationships

Close relationships between dissimilar Close relationships between dissimilar organisms are forms of organisms are forms of symbiosissymbiosis..A relationship in which one partner benefits but A relationship in which one partner benefits but the other is not affected is called the other is not affected is called commensalism.commensalism.A relationship in which both partners receive A relationship in which both partners receive benefits from the relationship is called benefits from the relationship is called mutualismmutualismA relationship in which one partner benefits at A relationship in which one partner benefits at the expense of the other partner is called the expense of the other partner is called parasitism.parasitism.

Finding Nemo

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Boundaries & BarriersBoundaries & Barriers

While it may seem as if there are no limits While it may seem as if there are no limits to movement for organisms in the oceans, to movement for organisms in the oceans, they can be restricted both horizontally they can be restricted both horizontally and vertically by a number of different and vertically by a number of different types of invisible barriers.types of invisible barriers.

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Boundaries & BarriersBoundaries & Barriers

Barriers to movement in the oceans can be created by Barriers to movement in the oceans can be created by changes in a number of different physical properties that changes in a number of different physical properties that will restrict the movement of specific organisms. will restrict the movement of specific organisms. – temperature, pressure, salinity, turbidity, and sunlight, temperature, pressure, salinity, turbidity, and sunlight, – sea floor topography that may isolate basins from one another.sea floor topography that may isolate basins from one another.

In general, the significance of barriers decreases with In general, the significance of barriers decreases with increasing depth because of the nearly constant physical increasing depth because of the nearly constant physical properties of deep water.properties of deep water.Horizontal boundaries in shallow water are often caused Horizontal boundaries in shallow water are often caused by two or more water masses meeting.by two or more water masses meeting.Vertical boundaries in shallow water are often the result Vertical boundaries in shallow water are often the result of strong thermoclines, haloclines, and/or pycnoclines.of strong thermoclines, haloclines, and/or pycnoclines.

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A complex interaction among kelp, sea urchins, A complex interaction among kelp, sea urchins, and sea otters controls the kelp community.and sea otters controls the kelp community.

MacrocytisMacrocytis is a brown algae that grows is a brown algae that grows up to 40m long in extensive beds on up to 40m long in extensive beds on North America’s Pacific continental North America’s Pacific continental shelf.shelf.

Sea urchins feeding on kelp detach Sea urchins feeding on kelp detach them from this holdfast and devastate them from this holdfast and devastate the kelp beds.the kelp beds.

Sea otters prey on sea urchins, a Sea otters prey on sea urchins, a balance is kept in the systembalance is kept in the system

The Ocean Sciences: Ecology of the Giant Kelp Community

Life in the Ocean. 2 Marine Biology The tremendous variety of marine organisms that inhabit the...

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