 Warm-up: (10-14-15)
*Ch.7-2 video notes/rubric out for stamp!
*Biobottle plans in the HW tray!
 1. Why should we protect amphibians? (2 reasons)
 2. Explain how the American Alligator is an example of a keystone species.
 3. How would an invasive plant affect a community?
 4. Contrast foundation, invasive, and native species.
 Q/A:
 What is symbiosis?
 What is an epiphyte?
 Contrast predation and parasitism.
 Contrast endo and ectoparasites.
 Contrast intra and interspecific competition
 Contrast commensalism and mutualism.
 The relationship between fire ants and native ant populations is best described as (intra, inter) specific.
 Ch.5-2: Symbiosis
 Goal for today:
 Identify the symbiotic interactions as competition, predation, parasitism, mutualism, or commensalism
 SPECIES INTERACTIONS:
 Species can interact through:
 Competition
 Predation
 Parasitism
 Mutualism
 Commensalism
 Plants can compete too!
 Bunch grass is evenly spaced out due to competition for nutrients and space.
 This is an example of _____ competition.
 Competition
 Intraspecific
 Interspecific
 Interference
 Exploitation
 Interference competition – when two or more organisms directly try to limit access to a resource (some
humming birds defend particular trees)
 Exploitation competition – when one group uses a resource faster than another, indirectly limits a resource
 Ex. Plant removes nutrients/water from soil faster than its neighbor
 Protection from Predation
 What are some defense mechanisms used by prey to prevent being eaten?
 Armor
 Camouflage
 Chemicals
 Mimicry
 How does mimicry protect an organism?
 How is mimicry different from camouflage?
 Parasitism
 Parasitism: parasite feeds off of/harms the host but doesn’t kill it right away.
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Social parasite. Cricket pretends to be an ant. Hides his scent. Lives in the ants home and even gets fed.
Ex. Mussel larvae- hitch hike on the gills of a fish and take its blood. Then get dropped off at another location.
Ex. Wasp and caterpillar
Wasp lays eggs inside caterpillar
Eggs hatch and larvae eat the caterpillar avoiding vital organs to keep their food fresh
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Brood Parasitism
Cowbirds and Cuckoos: lay their eggs in another species nest
Parasitism is a ____ interaction.
+,+
+,-,+, neutral
-, neutral
Mutualism
Mutualism: both species cooperate and both benefit.
Saguaro cactus and white winged dove
Mutualism is a ____ interaction.
+,+
+,-,+, neutral
-, neutral
Commensalism
Commensalism: one species benefits, the other is not affected.
Ex. Bird living in a tree
Ex. Mackerel and shark: bumps against shark to get rid of parasites and loose scales
Commensalism is a ____ interaction.
+,+
+,-,+, neutral
-, neutral
Just when you thought it couldn’t get any more complicated….
Sloth has algae growing in its fur to help it camouflage with the lichen growing on the tree. Algae get a place to
live. (_________)
The lichen is a made up of a fungus and algae. Algae makes food for the fungus, fungus provides algae a home.
(________)
A moth lives in the fur and eats some of the algae. (__________)
The moth doesn’t hurt the sloth. (__________)
Check for Understanding:
I will show you some examples, write down your answers. Do not yell out the answers.
Here we go…
Athlete’s Foot: fungus that commonly attacks the feet
Termites: protozoa in their stomachs that break down the cellulose in wood
Bee and Flower