Transcript Community Ecology Chapter 27

Let’s Start…take handout, complete
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Do Now: pass up HW 
1. Define predator, prey, parasite
Essential Question: Explain how evolution
shapes the interactions among species in
an ecosystem
Goal: interdependence of organisms
Anticipatory Set: Why are
weasels so important?
Anticipatory Set:
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In most animal stories…..weasels are
notorious fiends that randomly kill all the
gentle creatures of their community.
People who are dishonest are often called
weasels. The fact is that weasels are
predators of rats and mice. Why are
weasels so important?
Community Ecology
Species Interactions
Chapt 21 lab
chapt 27 honors
Zebra Mussels on a Crayfish!
Brainstorm:
What type of
relationship do
you think these
two organisms
have? explain
Symbiosis
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A relationship
between different
species living in close
association with one
another!
5 Major Types of Symbiosis
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1.
2.
3.
4.
5.
predation
parasitism
competition
mutualism
commensalism
Predation
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Predator ??
Prey ??
Mimicry
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Deception, when a harmless species
resembles a poisonous or distasteful
species!
Plant-Herbivore
Interaction
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Secondary compounds – when chemicals are
synthesized from products of their
metabolism that are poisonous, irritiating,
or bad tasting.
Tobacco plants contain
Nicotine which is
Poisonous to insects!
- Poison Ivy (ex)
Parasitism:
One benefits & one is harmed!
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6 day old Purple Martin covered in blowfly
parasites
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Host
parasite
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Parasitism
One benefits & one is harmed!
 Elephantitis - caused by 3 specific kinds of
parasitic round worms
Parasitism
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Tapeworm!
Parasitism
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Bot Fly larvae
Parasitism
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Removal of the bot fly larvae
2 Kinds of Parasites
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Ectoparasites – external parasites, they
live on their host but do not enter the
hosts’s body ex: ticks, fleas, lice, leeches,
mosiquitoes
Endoparasites – internal parasites, live
inside the host’s body ex: malaria
parasites, tapeworms
The objective of the study was to determine the utility of leech
therapy in venous congested microvascular free flaps in which
venous outflow could not be established or surgical revision was
unsuccessful.
LEECH THERAPY!
Competition
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1. competitive exclusion: one species is
elliminatted from a community because of
competition for the same limited resources
2. resource partintioning: competition is most
intense between closely related species
that require same resources, each species
uses only part of available resources
Continue……
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3.
Character Displacement:
competitors may also
evolve niche
differences or
anatomical difference
that lessen the intensity
of competition ex:
Darwin’s finches!
Niche
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It’s way of life, role
species plays in it’s
envir. Includes range of
conditions that species
can tolerate, the methods
by which it obtains food
needed, resources the
no. of offspring it has it’s
time of reproduction and
all of its other interactions
with it’s envir.
Habitat
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The physical area
which an organism
lives.
Mutualism and Commensalism
Mutualism: both species derive some
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benefit
ex: pollinators!
Commensalism: one species benefits and
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the other is not affected.
ex: barnacles that attach themselves to
whales!
Mutualism
Commensalism
Succession
the gradual sequential regrowth of species in
an area
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Primary succession: development of a
community in an area that has not
supported life previously such as bare rock,
sand dunes or island formed by volcanic
eruption.
Secondary succession: replacement of
species that follows disruption of an existing
community.
Pioneer Species: small, fast growing and
fast reproducing (first to appear)
Climax community
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traditional description of succession is that
the community proceeds through a
predictable series of stages unitl it reaches
a stable end point