Homework due Tuesday Complete assignment, The Mystery of Easter Island (requires textbook) Read essay, Endless Interactions, pp. 658 After School help sessions Tues (6/6) and Weds (6/7) for: Nitrogen and Carbon Cycles Test Rescore work

Happy Monday! Submit The Wolves of Yellowstone Title a new page “Ecology in a Nutshell” Reminders: Start a Test Rescore this week and submit by Friday (6/9) in case you require a few submissions before reaching 100% Pasture Profits is due Tuesday

Ecology

Ecology, defined BBECPO Ecology is the study of how organisms interact with each other and their environment. BBECPO

Biomes “The world's major regions, classified according to the predominant vegetation and characterized by adaptations of organisms to that particular environment" 

Biodiversity A term given to the variety of life on Earth –between all species of plants, animals and micro-organisms.

Ecosystem All the organisms in a given area (“biotic” factors) as well as the abiotic factors with which they interact.  Abiotic Examples: Biotic Examples:

Biogeochemical/Nutrient Cycles Nitrogen Cycle Cycling of N2 gas, NO3 (nitrates), Netc (protein), NH3 (ammonia) Biotic and abiotic reservoirs Nitrogen fixation via bacteria Carbon Cycle Cycling of CO2 , C6H12O6 (glucose) and Corganic molecules Carbon fixation via plants Water Cycle Cycling of H2O (water) in biotic and abiotic reservoirs

Communities One “community” refers to all populations (i.e., various species) living together, interacting with each other, in a shared space.

Competes for space with Wrinkled Whelk (Snail) Great Blue Heron Supplies energy to Lives in Becomes Chinook Salmon Smolts Competes for space with Isopods California Mussel Wrinkled Whelk (Snail) Snails Dungeness Crab Acorn Barnacle Eelgrass Polychaete Worms Zooplankton Phyto-plankton Detritus Diatoms Review interactions. How many trophic levels? Primary producer(s)?

The Effect of the Introduction of: The Japanese Mudsnail, a non-native, invasive species An introduced species thought to cause damage to an existing ecosystem Shoreline Development (humans!)

Competes for space with Wrinkled Whelk (Snail) Great Blue Heron Japanese Mudsnail - Eat diatoms - Stir mud into water Supplies energy to Lives in Becomes Chinook Salmon Smolts Competes for space with Isopods California Mussel Wrinkled Whelk (Snail) Snails Dungeness Crab Acorn Barnacle Eelgrass Polychaete Worms Zooplankton Phyto-plankton Detritus Diatoms

Shoreline Development Competes for space with Wrinkled Whelk (Snail) Great Blue Heron Supplies energy to Shoreline Development - Force of water due to sea wall rips up eelgrass beds Lives in Becomes Chinook Salmon Smolts Competes for space with Isopods California Mussel Wrinkled Whelk (Snail) Snails Dungeness Crab Acorn Barnacle Eelgrass Polychaete Worms Zooplankton Phyto-plankton Detritus Diatoms

Food Webs

Food Chains vs. Food Webs Compare and Contrast

Food Chains and Trophic Levels The word trophic derives from the Greek trophē referring to “food” or “feeding”. The trophic level of an organism is the position it occupies in a food chain. A food chain represents a succession of organisms that eat another organism and are, in turn, eaten themselves.

Happy Tuesday! Submit Open to notes from yesterday Pasture Profits The Mystery of Easter Island Open to notes from yesterday

Write a statement to explain why food chains are limited to only a few trophic levels. Extra Challenge: Incorporate heat, organic, and biomass in your response.

Ecological communities with higher biodiversity form more complex trophic paths. The greater the biodiversity, the more stable the ecosystem. Why do you think this is the case?

Food Web: Yellowstone National Park What could happen if the elk population was removed? What do King Bolete and Soil Bacteria represent? If the Idaho fescue was removed, what organisms may be directly affected? Indirectly affected? Why?

Reintroduction of the Wolves in Yellowstone National Park Discuss: Why were wolves removed from Yellowstone National Park beginning in 1914 and ending with the last wolf killed in 1944? What started occurring in the 1980s to 1990s to resume the balance back to the park? It has now been 2-3 decades since wolves were reintroduced back into Yellowstone. What changes have biologists observed in the park? Are these healthy or unhealthy?

Do you think it would have been better for the ecosystem if more wolves had been introduced in 1995? Why or why not? Explain why the wolf population declined after 2000. In which year was elk starvation greatest? Explain why so many elk died that year. Predict what might have happened if hunters had been allowed to kill half of the wolf population in 2005. How does the size of the elk population influence the number of wolves in the park? If no hunting is allowed, what natural mechanisms would control the size of the wolf population?

Describe the relationship you see between the predator and its prey. Why do prey species fluctuate so much more?

Removing the keystone of an arch causes it to collapse. Keystone Species: A species in an ecosystem which has tremendous importance in stabilizing an ecosystem in spite of the fact that the species is not very abundant. - Its removal has a cascade effect on countless other species in the ecosystem. - Not to be confused with dominant species, which describes the most common (abundant) species in an ecosystem. Removing the keystone of an arch causes it to collapse.

Community Interactions Predator-Prey Competition Symbiosis sym = together bio = life/living Mutualism Commensalism Parasitism

Predator-Prey Predation: an interaction between species in which one species, the predator, uses the other, the prey, for energy. Predation is not to be confused with parasitism, in which one organism feeds on the cell contents, tissues, or body fluid of another species (the host). Parasites harm but usually do not kill their host.

Competition An interaction in which 2 or more species compete for resources due to inhabiting a shared space. Think siblings! Both species tend to experience some disadvantage. Whether it be for food, living space, shelter, or attention at college parties.

Symbiosis Symbiotic Types “sym” = together “biotic” = life related Mutualism + + Commensalism + 0 Parasitism + - Predation + -

Mutualism An interaction where both symbiotic organisms benefit. + / +

Commensalism An interaction where one organism benefits and the other is unaffected. + / 0

Parasitism + / - An interaction where one organism benefits (the parasite) and the other is at a disadvantage (the host).

Shifting Gears… If you traced a radioactive carbon atom from the primary producer level, could it end up in the eagle? Why or why not?

Observe both diagrams. What do they have in common?

The concepts of bioaccumulation and/or toxic magnification is shown in the images. Write a statement that explains this phenomenon. How might the cycle of this matter affect the health of an ecosystem?

Happy Wednesday! Finish lecture! Need a calculator Practice EOC Scenario Try one See how you did against scoring rubric Tips Repeat, if time, using the other practice scenario

Populations A group of members of a certain species (i.e., can interbreed and reproduce fertile offspring) that live in the same area.

Populations Things we examine in populations: Population Growth (graphs) Population Density Limiting Factors Carrying Capacity

Pasture Profits The carrying capacity of a biological species in an environment is the maximum population size of the species that the environment can sustain indefinitely, given the food, habitat, water, and other necessities available in the environment. Thanks and nicely said, Wikipedia!  What was the carrying capacity in Pasture Profits? What is the relationship between resources and carrying capacity in a particular ecosystem?

Population Density How many organisms of one population occupy an area. “Whoa, I think that the population density of Homo sapiens in Mill Creek is far less than that of the population density of Homo sapiens in China” Population = # of individuals in a population Density Area (square miles)

# of individuals in a population / Area (square miles) Try these… Population Density = # of individuals in a population / Area (square miles) Calculate the human population density of: A town that is 25 square miles and has a population of 8,341. The United States, which has an area of 3,539,225 square miles and a population of 298,444,215. China, which has an area of 3,705,000 square miles and a population of 1,357,000,000. A town that is 3.6 square miles and has a population of 18,828.

The Mystery of Easter Island What happened to the population of humans on the island over time? What factors limited the growth of the human population?

Observe the 2 graphs showing different populations carrying capacity Observe the 2 graphs showing different populations carrying capacity. What is the difference? What does this tell you about carrying capacities? S - Shaped Growth Curve J - Shaped Growth Curve

Limiting Factors

Discuss: What conditions are necessary for populations to increase rapidly?

Tips When writing a Procedure, always include: “Record data” “Repeat steps __ through __ two more times” “Measure the [initial] value” “Measure the [final] value” For Field Studies, when designing a new study, you CAN use their original steps and modify as needed, to reflect your new study EOC Packet Key and all Scoring Guides will be posted tonight at 4-5pm