1. Ecology-Chap 2
Study of interactions of organisms
with each other and their
environment

2. Level of organization
• Cells -> organisms -> population -> community
-> ecosystems -> biosphere
– All connected so they all affect one another
• When something happens to one; all affected –
domino effect

3. Environment
• All external factors affecting an organism
– Abiotic –
light, temperature, salinity, turbidity, weather
conditions, pH, waves, currents
– Biotic-predators, prey, parasites, etc.

4. Habitat-Where they live
– Examples: rocky shores (cali and Maine), sandy
shores (jax beach), mangroves (south FL), coral
reefs (keys), deep sea (Hydothermal vents

5. Niche –Role in ecosystem “their job”
• Can be viewed on an a abiotic side OR a biotic
side, looking at both at same time gets very
complex an is difficult to illustrate
• Lets take a look at the biotic side……

6. Competition
• Occurs when organisms require same limited
resources (food, light, space, mates)
– Can be within same species (intraspecific) OR
between similar species (interspecific)
– Prevents 2 groups of organisms from occupying
the same niche
– Usually no 2 organisms can use exactly the same
resources in exactly the same place at exactly the
same time……..WHY?????????

7. Sooo…..
• Some species have adaptations that have
allowed them to be successful?
– Plankton feeding fish
• Sea bass- eat close to reef
• Damselfish-each futher away (adaption to feeding in
different location)
• Now these two species are feeding on the same thing
BUT not in the same space.

8. Predator Prey relationships
• Number of individuals is dependant on the
abundance of their food source.
– Ex if the number of bull sharks were too increase
to massive numbers because of a lot of food, then
the number of fish they eat would go down, then
eventually bull sharks would decrease

9. Keystone species
• Has great effects on foodwebs/ecosystems
• Increases biodiversity
• Example sea otters in Pacific Coast
(Washington State)

10. • http://www.youtube.com/watch?v=LYtxz1dqZ
W0&feature=related&safety_mode=true&per
sist_safety_mode=1&safe=active

12. Symbiosis-”living together”
cohabitating
• 3 main types
– 1. mutualism- both benefit
– 2. commensalism- one benefits, other neither
harmed nor helped
– 3. parasitism- one lives off another
• Parasite benefits and host is harmed

13. Mutualism
• Clownfish gets home
• Anemone-gets protection so other
fish don’t eat tenacles
So dependent on each other that need each other
to survive. Coral give zooxanthellae N, P, and CO2
and zoo give corals carbohydrates

14. Commensalism
• Shark-no
benefit or
harm; remoras
get free ride
and eat
leftover food
Barnacle gets ride and place to live; whale
no benefit or harm

15. Parasitism
• Sea
Cucumber –
pearl fish
feed on
respiratory
tissue and
reproductiv
e organs

16. Do pg. 31 # 1-4 Short Answer