COPY!!!
Define!
• Producer:
• Consumer:
• Autotroph:
• Heterotroph:
• Food Chain:
• Food Web:
• Trophic Level:
• Predator
• Prey
Energy is transferred in ecosystems:
• Producers give E to Consumers
• Food chains show flow of energy (arrows  show where energy is going)
• Trophic level a single step in the food chain
• A step in the transfer of energy and matter in an ecosystem
• Primary Producers (green plants, algae, and some types of bacteria)
• AUTOTROPHS make their OWN food
• Use Photosynthesis and Chemosynthesis to change inorganic chemicals into molecules that they use for ENERGY!!!
• Plants and bacteria
• Consumers
• HETEROTROPHS must eat different things to get their E…canNOT make their own GLUCOSE
• Primary consumers, secondary consumers, tertiary consumers
•
•
•
•
•
Herbivores: eat plants (Brine shrimp, zooplankton, mullets)
Omnivores: eat plants and animals (piranhas, sea bass)
Carnivores: eat other animals (sharks, seals, tuna)
Detritivores: eat organic plants and animal matter (sea stars, crabs)
Decomposers: get energy from decaying DEAD organic matter (bacteria, marine worms,
seaweed, shrimp, and sea urchins)
Trophic Levels
•Each link in a food
chain is known as a
trophic level.
•Trophic levels
represent a feeding
step in the transfer of
energy and matter. in a
Food chain- simple model
that shows how matter and
energy move through an
ecosystem
Food web- shows all possible
feeding relationships in a
community at each trophic level
• Represents a network of
interconnected food chains
Predatory starfish eating a
mussel
large numbers of fish of the same
species and approximately the same
size.
‘school’
 The formation of a shoal has a number of advantages to the fish, including:
1. increased hydrodynamic efficiency – fish may save energy by swimming
together in a coordinated way
2. avoidance of predation – large shoals of fish may confuse a predator; also, with
so many eyes, it is more likely that a predator will be seen
3. increased foraging efficiency – the time taken to find food is decreased
4. reproductive advantage – there is an increased chance of finding a mate within
a shoal than there is for an individual fish
 Both tuna and sardines form shoals. When threatened by predators, sardines
can form massive ‘bait balls’ consisting of many hundreds of thousand
individuals.
Physical and Biological Environmental Factors Affect
Communities
Range of tolerance to a physical factor – in this case,
temperature – for a population of organisms.
Growth Rate and Carrying Capacity Are Limited
by Environmental Resistance
• The J-shaped curve of population
growth of a species is converted
to an S-shaped curve when the
population encounters
environmental resistance.
• The physical or biological
conditions responsible for the
cessation of growth are called
LIMITING FACTORS
Population Density and Distribution Depend
on Community Conditions
A random distribution implies that the position of one organism in a bottom community in no way influences the
position of other organisms in the same community.
Clumped distribution occurs when conditions for growth are optimal in small areas because of physical protection
(in cracks in an intertidal rock), nutrient concentration (near a dead body lying on the bottom), initial dispersal (near
the position of a parent), or social interaction. (MOST COMMON IN NATURE)
Uniform distribution with equal space between individuals, such as the arrangement of trees we see in orchards, is
the rarest natural pattern of all.
Organisms in Communities Can Exist in
SYMBIOSIS
• Symbiosis is the close interaction of the
lives of two species:
• Corals and Zooxanthellae
(photosynthetic algae)
• Cleaner fish and grouper
• Chemosynthetic bacteria and tube
worms
What are some types of symbiotic interactions?
– Mutualism – both organisms benefit in these relationships. An example is sea
anemones and anemone fish.
– Commensalism – one organism benefits, the other is not helped or harmed.
Parasitism – one of the organism benefits (parasite),
but the other is harmed (host).
• Obtain their nutrients from their host
Ecotoparasites: live on the outside
of their host. Ex: fish lice
Endoparasites: live inside their host,
inside the digestive system, attached to their
gills, or within muscle tissue.
Ex: Nematodes also known as roundworms
Marine Communities Change As Time Passes
• Marine communities change through time. Changes can occur
slowly due to climate cycles or seafloor spreading, or quickly due to
factors such as volcanic eruption.
• A climax community is a stable, long established community.
• If a climax community is disrupted, it may be restored through the
process of succession.
Primary
• Succession
on Succession
land that occurs on
surfaces where no soil exists
• Volcanic eruptions
• Glaciers melting
Secondary Succession
• Succession following a disturbance that destroys a
community without destroying the soil
• Natural
• hurricane
• fires
• Human disturbances
• Farming
• Forest clearing
• Pollution (oil spills)
Succession also occurs around hydrothermal vents in the deep oceans:
1. first organisms to grow around a vent are…bacteria, which are followed by
small crustaceans, molluscs, crabs and fish.
2. Eventually, a complex community consisting of many different species is
established.
3. One of the first animal species to inhabit the area around a
hydrothermal vent is the tube worm, Tevnia.
4. This species is replaced by the larger and faster growing tube
worm Riftia.
 Tube worms form symbiotic relationships with chemosynthetic bacteria,
which provide organic substances directly to the tissues of the tube
worms.
Rocky Intertidal Communities Are Densely
Populated despite Environmental Rigors
Although the rocky shore looks like a very difficult place
for organisms to make a living, the rocky intertidal zone
- the band between the highest high-tide and lowest
low-tide marks on a rocky shore - is one of Earth’s most
densely populated areas.
A Pacific coast tide pool and intertidal shore. (left) A
diagrammatic view. (right) Key
Rocky Intertidal Communities Are Densely
Populated despite Environmental Rigors
The relationship between amount of exposure and vertical zonation in a rocky intertidal
community. (a) A graph showing intertidal height versus hours of exposure. The 0.0 point on the
graph, the tidal datum, is the height of mean lower low water. (b) Vertical zonation, showing four
distinct zones. The uppermost zone (I) is darkened by lichens and cyanobacteria; the middle zone
(II) is dominated by a dark band of the red alga Endocladia; the low zone (III) contains mussels
and gooseneck barnacles; and the bottom zone (IV) is home to sea stars (Pisaster) and anemones
(Anthopleura). The bands in the photograph correspond approximately to the heights shown in
the graph.
Coral Reefs Are the Most Densely Populated
and Diverse Communities
The coral reef habitat.
(a) A diagrammatic view.
(b) Key
Hydrothermal Vents and Cold Seeps
Support Diverse Communities
The path of water associated with a hydrothermal vent. Seawater enters the fractured seabed near an active
spreading center and percolates downward, where it comes into contact with rocks heated by a nearby magma
chamber. The warmed water expands and rises in a convection current. As it rises, the hot water dissolves
minerals from the surrounding fresh basalt. When the water shoots from a weak spot in the seabed, some of
these minerals condense to form a “chimney” up to 20 meters (66 feet) high and 1 meter (3.3 feet) in diameter.
As the vented water cools, metal sulfides precipitate out and form a sedimentary layer down-current from the
vent. Bacteria in the sediment, in the surrounding water, and within specialized organisms make use of the
hydrogen sulfide (H2S) in the water to bind carbon into glucose by chemosynthesis. This chemosynthesis forms
the base of the food chains of vent organisms.
Bottom current
Precipitation
FeO(OH) MnO2
Chimney
Precipitation
CaSO4 FeS
Sedimentation
Seawater seepage
H2S in water
Basalt
Basalt
Precipitation
FeS, FeS2, CuFeS2
350ºC
(660ºF)
350ºC
(660ºF)
Stepped Art
Fig. 16-21, p. 453