Ch 6

• http://www.nytimes.com/2007/04/24/science/24bees.html

• http://www.nytimes.com/2007/09/07/science/07bees.html

• http://www.nytimes.com/2007/08/29/us/29cnd-highway.html?_r=1

11-3 ATB• Why did your culture cups in the experiment lose

mass?

• Today:– Go over your tests– Discuss / finish compiling your data – finish graphing

• Save your work or post it to the wiki b/c this the last class day for it.

– Pre-quiz

11-4 ATB• Name the biome that covers the most area on earth.• Today:

– Begin ch 6 – research directions– Graphs and lab questions due Friday

Online Book – phschool.com/ access• Click science on the left

• Under “Student Resources” click “AP & Electives”• Choose “SS” or “SE”• CLICK THE FOLLOWING -- “Covered Titles”

“Science” “Withgott/Brennan, Environment: The Science Behind the Stories 3e AP* Edition”

• Student Registration• “NO” you don’t already have an account• Put in the password: SSPREN – CHOLI – LEVEL –

SCRAN – RIGOT - NURSE

• http://wps.aw.com/wps/media/access/Pearson_Default/4893/5010916/login.html

• APPeriod2

• Hakim12345

11-5 ATB• Figure out the phrase:

– N I NNNN I

• Today:– Begin the “Eternal Enemies” video– Continue working on your research

11-5 ATB• Get out the primary consumer productivity labs…look at question #6

• Cat – 5 kg (5000 g)

• Robin - 77 g

• Painted Lady - 0.5g

• Mallow Leaf – 0.2 g per leaf

• Calculate the # of robins, caterpillars & leaves needed to support the 5kg cat. (10% efficiency rate)– Start with how many robins must be consumed to

support the biomass of the cat

11-8 ATB

• Other than elephants, what is the largest land mammal?• Today:• “Eternal Enemies” Documentary• Work on your research

11-9 ATB

• Give an example of interspecific competition from the movie

• Today:– Finish the movie– Work on your projects

• 5000 g cat / 77 g/robin = 65 robins / cat (but with only 10% efficiency of the energy transfer, you must multiply 65 robins / cat x 10 = 650 robins / cat

• 650 robins x 77 g/robin = 50,050 grams of robins• (50,050 g robin / 0.5 g/butterfly) x 10 = 1,001,000

butterflies (to support 1 cat) • 1,001,000 butterflies x 0.5g/butterfly = 500,500 g of

butterflies• (500,500 g of butterflies x 0.2 g/leaf) x 10 =

25,025,000 g of leaves (to support 1 cat)

#7• 1g

• 10 g

• 100g

• 1000g

11-10 ATB

• What is siblicide or fratricide?

• Today:– Finish your projects– Start presenting them tomorrow

11-11 ATB

• Describe the leaders of the lion pride and hyena clan• Today:

– Begin presentations

11-12 ATB

• Describe cryptic coloration– Today:

• Continue with our presentations

11-12 ATB

• What is batesian mimicry

• Today:– Presentations!

11-16 ATB

• What is herbivory?

• Today:– Continue presentations

11-17 ATB

• Generally describe the rainfall and temperature in the savanna

• Today:– Finish presentations?– Test Friday?

11-18 ATB• What are some ways we could possible control invasive species?– Best is to prevent their introduction– Remove manually– Toxic chemicals– Drying them out– Depriving of oxygen– Stressing them

• Heat, sound, electricity, carbon dioxide, ultraviolet light

• Today– Finish presentations– Work on review sheet– Test…tomorrow?

This lecture will help you understand:

• Species interactions• Feeding relationships,

energy flow, trophic levels, and food webs

• Keystone species • The process of succession• Potential impacts of

invasive species• Ecological restoration• Terrestrial biomes

Case Study: Black and white and spread all over

• Small, black and white shellfish• Introduced to Lake St. Clair,

Canada, in 1988, in discharged ballast water

• Within 2 years, the zebra mussels invaded all 5 Great Lakes

• Populations grew exponentially – No natural predators, competitors, or

parasites

• Hundreds of millions of dollars of damage to property

Species interactions

• Species interactions are the backbone of communities

• Most important categories– Competition = both species are harmed– Predation, parasitism, and herbivory = one

species benefits and the other is harmed– Mutualism = both species benefit

Competition • Competition = relationship where multiple organisms

seek the same limited resources they need to survive:– Food - Water– Space - Shelter– Mates - Sunlight

• Intraspecific competition = between members of the same species– High population density = increased competition

• Interspecific competition = between members of 2 or more species– Leads to competitive exclusion or species coexistence

Results of interspecific competition

• Competitive exclusion = one species completely excludes another species from using the resource

• Species coexistence = neither species fully excludes the other from resources, so both live side by side– This produces a stable point of equilibrium, with stable

population sizes– Species adjust to minimize competition by using only a part

of the available resource

Niche: an individual’s ecological role

• Fundamental niche = when an individual fulfills its entire role by using all the available resources

• Realized niche = the portion of the fundamental niche that is actually filled– Due to competition or other species’ interactions

Resource partitioning• Resource partitioning

= – when species divide

shared resources by specializing in different ways

• Ex: one species is active at night, another in the daytime

• Ex: one species eats small seeds, another eats large seeds

Effects of resource partitioning

• Character displacement = – competing species evolve physical characteristics

that reflect their reliance on the portion of the resource they use

– Ex: birds that eat larger seeds evolve larger bills– Ex: birds that eat smaller seeds evolve smaller

bills

Competition is reduced when two species become more different

Predation

• Exploitation = one member exploits another for its own gain – Predation, parasitism, herbivory

• Predation = process by which individuals of one species (predators) capture, kill, and consume individuals of another species (prey)– Structures food webs– Influences community

composition through number of predators and prey

Effects of zebra mussels

• Zebra mussels eat phytoplankton and zooplankton– Both populations decrease in lakes with zebra mussels

• They don’t eat cyanobacteria – Population increases in lakes with zebra mussels

• Zebra mussels are becoming prey for some North American predators:– Diving ducks, muskrats, crayfish, flounder, sturgeon,

eels, carp, and freshwater drum

Effects of predation on populations• Increased prey populations increases predators

– Predators survive and reproduce• Increased predator populations decrease prey• Decreased prey population causes starvation of

predators • Decreased predator populations increases prey

populations

Natural selection

• Natural selection leads to evolution of adaptations that make predators better hunters

• Individuals who are better at catching prey:– Live longer, healthier lives – Take better care of offspring

• Predation pressure: prey are at risk of immediate death– Prey develops elaborate defenses against being

eaten

Organisms evolve defenses against being eaten