Transcript 04Populations,_Commu..

Ecology
 Study of the patterns of
distribution and
abundance of plants,
animals, and other
organisms
 Research organisms,
populations,
communities, and
ecosytems
Populations and Communities
 Populations are groups of individuals of the same
species living in the same geographic area
 Size of the area can vary
Communities
 The interactions of
populations are referred
to as communities, as
populations are generally
not isolated
 Communities are
influenced by
competition, and
predator-prey
relationships
 Also influenced by
moisture, hours of sunlight
 Communities change;
process of change is called
succession
 Organisms that are the
first to arrive in barren
landscape are called
pioneer species, as they
can survive harsh
conditions (like lichen)
Ecosystems
 Community of living organisms
 Includes non-living and living organisms, and the
interactions among them
 There can be an ecosystem within an ecosystem!
 A tree can be an ecosystem, and then it is part of
woods, and so forth
 Ecosystems and their interactions make up the
biosphere (largest ecosytem)
Biomes
 We already discussed these
 The temperature, moisture, sunlight, and more will
influence the vegetation and the organisms that will
live in any one place
 We studied terrestrial and aquatic biomes
Habitat and Niche
 Habitat is a place with a specific set of characteristics,
both biotic and abiotic
 Each type of organisms found in a habitat in which is
physical, physiological, and behavioural adaptations
equip it to survive and reproduce
 Niche is the role of an organism in its community
 The niche can include how they interact with other
members of the community – what they eat, what eats
it, who competes with it, and their living space
Diversity
 Organisms have adapted to life in certain conditions, and
can tolerate only minor changes in environmental
conditions
 found in very specific places and would not survive outside
these places
 Specialized organisms can tolerate the changing conditions
of light, moisture, and temperature along the shores
between high and low tides
 Few can survive the total darkness and extreme pressure of
the ocean floor
Diversity continued
 The more diverse an ecosystem,
the more it can tolerate change
 Ones with little diversity, if one
organism is lost, the entire food
web could collapse
 Example of adaptations:
 Deep ocean animals have huge
mouths, expandable stomachs
so that when they find food,
they can keep it all, and some
have light-emitting organs
Adaptations
 Size – things that are small
are harder to detect (ie.
Phytoplankton)
 Transparent body – hard to
see (ie. Jellyfish)
 Cryptic coloration – from
below they blend with
light from the sky and from
above, they blend with the
dark water. (ie. Cod, tuna)
 Disruptive coloration –
hides the outline of the
fish. (ie. Clown anemone
fish – coloration works well
with coral)
 Mimicry of surroundings –
colored and shaped to
appear part of their
surroundings (ie.
Flounder)
 Bioluminescence - have
photophores which emit
light. (ie. Lantern fish)
Structure of Ecosystems
 Each species is in its trophic level, depending on its
level of nutrition
 Autotrophs make their own food; they are also known
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as primary producers
Heterotrophs rely on others for their food
Herbivores are plant eaters and primary consumers
Carnivores are meat eaters and secondary consumers
Decomposers obtain their energy from eating leftover
or waste materials (including feces, dead bodies)
Decomposers break large molecules into smaller ones
and return them to the abiotic environment