OUR PLANET Unit 1-3a Energy in the Ecosystem I Give Up. What’s black & white and read all over?

How Do Ecosystems Work? The Sun - The source of all energy on Earth * Without the sun, our planet would be cold and dark without anything to eat and fresh water would be scarce! Producers (Autotroph) – Make their own food; Ex: Plants Photosynthesis changes solar energy into chemical energy Without producers there wouldn’t be any food for the… Consumers (Heterotrophs) – Obtain energy from other organisms; Ex: Animals, Fungi and many bacteria Which are these? Consumer Producers ???

Types of Consumers There are four different types of consumers… Why is a vegetarian still considered an omnivore? Types of Consumers Energy SourceExamples Herbivoreproducerscow, pleco Carnivore other consumers snake, vulture Omnivore producers & consumers people, bears Decomposer decaying matter fungi & bacteria

Can Life Exist Without The Sun? *Without the sun, life on earth could still exist due to… Chemotrophs – These deep ocean bacteria get energy from hydrogen sulfide that’s released from volcanic vents These bacteria support entire ecosystems that have never seen the sun! Could life exist on Titan, one of Saturn’s moons, that’s almost 1 billion miles from the sun? Maybe… It would need a volcanic core to keep it’s ocean from freezing.

Storing & Using Energy What does a plant need to survive? Photosynthesis uses Water, Carbon Dioxide and Sunlight to create Sugar (energy stored as glucose) & Oxygen (waste) H 2 O + CO 2 + Energy  C 6 H 12 O 6 + O 2 While plants use photosynthesis to create stored energy, plants & animals have another process to use the energy… Cellular Respiration – Plants and animals use Sugar and Oxygen to get energy, releasing water & carbon dioxide C 6 H 12 O 6 + O 2  H 2 O + CO 2 + Energy What do you notice about these equations?

Let’s Review… What have you learned in this unit? 1. Describe how energy from the sun can be used by a wolf. 2. Describe the four different types of consumers. 3. How is matter from producers recycled in the environment? 4. How could life exist on one of Saturn’s moons? 5. Explain the similarities and differences between photosynthesis and cellular respiration.

OUR PLANET Unit 1-3b Energy Transfer

How Energy Flows Trophic Level – Each step in which energy and matter are transferred within an ecosystem; Ex: Energy pyramid Most of the energy taken in by an organism at one trophic level is used before that energy can be passed to the next level. Organisms use their energy to complete life’s processes. Which level has the highest population? Which has the lowest population?

An Analogy for Trophic Levels Think of our school population in terms of size : –Bottom = students – biggest population –Above the students are the teachers –Top of the pyramid is smallest population: Administration (Mr. Ross and the Vice Principals)

How Energy Flows The 10% Law – Only 10% of the energy at each trophic level is passed on to the next and 90% is used or lost. Carnivores are found at the top. And just ~50 Calories from the grass are passed on to the lion. Next are the herbivores. But only ~500 Calories are passed on to the giraffes. At the base of every pyramid are producers.. Make ~5,000 Calories of energy/m 2 each year.

A Closer Look At Trophic Levels Food Chain – A specific diagram that shows how energy flows from one organism to another Why did the bald eagle population drop so much in the 1970s? Thin eggs were being crushed by the mom before they could hatch. A look at the food chain showed that DDT, a powerful pesticide, became more concentrated as it moved up each trophic level. In part, due to the damage caused by DDT, bald eagles were on the endangered species list from

Seeing The Big Picture Food Webs – Shows multiple, interconnected food chains; A more accurate image of how organisms survive in an ecosystem Each year, 1-3 million people are killed by a deadly disease known as… Malaria! It is transmitted, person to person, by the mosquito. Wouldn’t it be great if we could kill all the mosquitoes in the world? How many other creatures would be affected if mosquitoes vanished?

Where Did All Of These Come From? Invasive Species – A foreign plant/animal that negatively affects an ecosystem; Species grow with few predators Compete with native species for resources Overpopulation Zebra Mussel – Carried by water from Russian boats. Each year they cause $500 million in damage to pipelines in our country. Asian Long-Horned Beetle – Arrived in wood from China, They burrow holes into many types of American trees ultimately killing them;

Ecological Succession Definition: Gradual process of change and replacement of some or all of the species in a community 2 types: –Primary Succession: occurs on a surface where no ecosystem existed before – Secondary Succession : occurs on a surface where an ecosystem existed before. Disturbed or disrupted by humans or animals or natural disasters. Pioneer Species: first organisms to colonize a newly available area. Usually lichen. –When a community is stable it is called a climax community

Primary Ecological Succession

Secondary Ecological Succession

Let’s Review… What have you learned in this unit? 1. What is a trophic level? 2. Why does an energy pyramid typically only have 4-5 levels? 3. Which types of organisms are found at each level of an energy pyramid? 4. Give an example of when studying a food chain would be important. 5. Give an example of when studying a food web would be important.

OUR PLANET Unit 1-3c Species Interactions

What’s A Niche? Niche – A species role in the environment including… (Let’s use squirrels for example…) Its habitat (Squirrels are common in forests and build nests in trees) Everything it needs to survive (It eats nuts, bird eggs and other small organisms) Every interaction it has with other species (It disperses nuts, limits other populations, its waste fertilizes the soil, & it is food for many predators)

Overlapping Niches Squirrels are not the only species to live in trees, or eat nuts, or hoard for the winter so this creates… Direct Competition (-,-) – When species, or individuals, attempt to use the same limited resource Sometimes species don’t even recognize their competition! Indirect Competition (-,-) – Occurs even when the species may never come into direct contact Ex: Owls are nocturnal… Snakes are diurnal… So how do they compete? Are there enough mice for both of them?

How Species Interact There are four types of species interactions Predation(+,-) – When a predator uses its prey as a source of food; Ex: Wolves and rabbits Parasitism(+,-) – A parasite lives on or in a host without killing it immediately; Ex: Dog with ticks & heartworms Why doesn’t the parasite want to quickly kill the host?

How Species Interact Mutualism(+,+) – A relationship between two species in which both benefit; Ex: Acacia trees & ants, Humans and trees What are the benefits for the tree and the ants? Commensalism(+,0) – One organism benefits but the other isn’t helped or harmed; Ex: An orchid and trees How does the orchid benefit by climbing the tree?

How Species Interact-A Giants Analogy! Mutualism - Eli Manning throws a touchdown pass to Hakeem Nicks. Manning gets the completion and Nicks gets the touchdown for the team. (+, +) Commensalism - Giants have a bye week. The team benefits from the rest but no other teams are negatively affected. (+,0) Predation/Parasitsm- Cory Webster closely follows his man Desean Jackson. When Vick throws the ball, Webster intercepts it. (+, -) Competition - Two opposing receivers go up in the air for the ball and both get injured. ( -, -)

Who Is Who? Mimicry – When two species have a similarity (in sound, scent, behavior, or appearance) that offers protection Milk Snake – Harmless but shares the same colors as the deadly coral snake; Red on black-Friend of Jack but Red on Yellow-Kill a Fellow… Can you tell which is which? Dead Leaf Mantis – What do you think this praying mantis is trying to mimic? Can you see her?

Let’s Review… What have you learned in this unit? 1. How big is your niche? 2. What causes competition and who benefits from it? 3. Compare & contrast parasite- host with predator-prey. 4. Describe the mutualistic relationship between a termite and the bacteria in its stomach. 5. Why are there so few examples of relationships that are purely commensalism?