Ecology Our Environment A Quote This we know... The earth does not belong to man, man belongs to earth. All things are connected, like the blood which connects one family. Whatever befalls the earth befalls the children of the earth. Man did not weave the web of life - he is merely a strand in it. A Quote We do not inherit the earth from our ancestors, We borrow it from our children. -Native American Proverb Whatever he does to the web, he does to himself. - Chief Seattle, 1854 Do Now Find your match and draw a picture that describes the vocabulary word. Be prepared to share your drawing with the class. ECOLOGY What is it? The study of relationships b/w living things (plants, animals, & other organisms) with one another & their physical surroundings (natural resources) such as air, soil, and water. 1
Ecologists study ecology at different levels PHYSICAL ENVIRONMENT Abiotic = non-living factors List Some Abiotic Factors? Abiotic Factors Light (intensity & duration) Temperature range (fluctuations, daily & seasonal) Water amt. Landscape (topography) Soil (type, minerals, ph) LIVING ENVIRONMENT Biotic = living factors List Some Biotic Factors? Temperature (warm temp-less O2; cold watermore O2) CO2, Oxygen amount LIVING ENVIRONMENT Biotic (living) Factors Plants Animals Fungi Bacteria Protozoa Everything alive! Ecological Organization (Biotic) Species A group of similar organisms capable of inter-breeding and producing fertile offspring Example: Bullfrogs Population All the members of a single species inhabiting a given location Example: All the Bullfrogs in a lake Community All the interacting populations in a given area Example: All the fish, frogs, plants, etc. in a lake 2
Ecological Organization (Biotic & Abiotic) Ecosystem All the living (biotic) & nonliving (abiotic) factors interacting (functioning together) as an independent, stable system These interactions result in a balance that allows the ecosystem to be selfsustaining (independent) Ecological Organization (Biotic & Abiotic) Biome A large geographical area with similar vegetation types Biosphere - all ecosystems on Earth where all life is found Land Water Air Ecological Organization Test Yourself (Organizational Levels) Simple Complex A guppy =? A hermit crab =? A cat =? A dog =? All the hermit crabs in Mrs. Reece s house =? All the cats in Mrs. Reece s house =? All the animals (people too!) in Mrs. Reece s house =? Mrs. Reece s house =? Copy Into Your Notebook Analyze The Picture & Identify Each (community, habitat, ecosystem, population) Pond Minnows Aquatic plants Entire population of different organisms The community of animals, plants and micro-organisms, together with the habitat where they live 3
Answers Pond (Habitat) Minnows (Population) Aquatic plants (Population) Entire population of different organisms (Community) The community of animals, plants and micro-organisms, together with the habitat where they live (Ecosystem) Factors For A Stable Ecosystem & Organism Survival Ecosystems Self-sustaining ecosystems must have: Constant source of energy Ability to change this energy into organic molecules Cycle minerals & nutrients between organisms & the environment Organism Requirements Basic Needs Food Water Shelter Other Needs Reproductive Social Organisms go about getting these needs in very specific ways! Ecosystems & Populations Populations change size based on the resources available. Without limitations, populations increase. Limiting Factors Abiotic & Biotic are examples of limiting factors. Factors in the environment can limit the size of a population- called limiting factors 4
Population Limiting factors Abiotic Light Temperatures Moisture Soil Nutrients ph Pollutant concentrations Biotic Food Availability Disease Predation Competition from other organisms Mating opportunities Examples Abiotic 1. Extreme heat - limits type of species to survive in desert 2. Water temp. - limits types of fish that live in water Biotic 1. Predator-prey relationships (Coyote predatorlimits # of deer (prey) in forest) Factors Limiting Population Size 1. Predator-prey - Predation (1 organism eats another) 2. Competition 1. Predator-Prey: Whose Who? Controls (limits) population size, if left undisturbed population remains BALANCED. Predator = kills & eats organism Prey = organism eaten 3. Carrying Capacity Case Study: The Lynx & The Hare The rise and fall in numbers of Canadian lynx and its favorite prey the snowshoe hare. The two populations were estimated each year for some 75 years from the number of animals caught by fur traders. The lynx population was found to rise and fall in a ten-year cycle, with that of the hare following two years behind. No other cat is so dependent on a single prey species, which is why there is such a clear pattern of interdependence between the two populations. An Interdependent Relationship 5
Predator-Prey Dynamic 2. Competition The relationship (graph) between the 2 will look similar. Ex: If prey population increases, so does the predator population http://www.bbc.co.uk/schools/gcsebitesize/science/edexcel/ environment/populationsandpyramidsrev6.shtml Organisms can compete for the same resources such as food, shelter, territory (space), etc. Competition can be between members of the same species or different species Competition Competition When resources are FINITE (limited) & the demand for resources is greater than the supply ORGANISMS COMPETE! Plants compete with each other for: light (for photosynthesis) water, and nutrients (minerals) Animals compete with each other for: food water Mates ( for reproduction) living space Reducing Competition To reduce competition for food different species evolve to NOT occupy exact ecological niches. Ex: Different finch species feeding in spruce tree An Ecological Niche The specific role or job that an organism plays in its environment Its daily routine What the organism does in its environment Where & how they get food Where & how they hide Where & how they nest Where & how they breed Etc., etc., etc., etc., etc.,. 6
3. Carrying Capacity The total number of organisms that a certain area can support. Competition between 2 Paramecium species. One species will win, the other will lose. Organisms DO NOT overpopulate due to FINITE resources like food, space, H2O Carrying Capacity Birth rate = death rate population - No increase Wrap-Up: Fill In Population Size May Be Limited By # squirrels in 1 square mile of a forest Predators Competition (food, space, mates) Finite Resources (H2O, food, space) Disease Human Disturbances (habitat destruction) Activity: Answer These Questions Based on Your Analysis (On Board) Name some decomposers. What role does the tree trunk play for the insects, caterpillars, & larvae? Identify the different ecological niches for the following organisms: - squirrels, fungi, bees, blue tits, sparrow hawks Do the bluetits & squirrels inhabit the same tree? Do the bluetits & squirrels occupy the same or different niche within the oak ecosystem? Oak Tree Ecosystem Each zone of the tree is home to a distinctive community of organisms 7
Answers Bacteria, woodlice, and earthworms feed off last year's leaves, acorns & fungi grown on its roots The trunk layer provides shelter or food to insects, caterpillars and larvae. Squirrels (gather acorns), fungi (grows on roots) bees (gather pollen, nectar), bluetits (hunt moth larvae), sparrowhawks (hunt small birds) Yes Different niches Nutritional Needs In Ecological Communities Nutritional Relationships How do organisms acquire nutrients and energy? Make their own food--autotrophs OR Get it from other organisms--heterotrophs Autotrophs Auto = self Also called producers Troph = food, feeding Synthesize their own food from inorganic materials & an energy source or convert solar energy into food energy -Ex: green plants Heterotrophs Hetero= different Also called consumers Troph= food, feeding Organisms are dependent on other organisms for food Categorized by what they eat and how they acquire it. 5 Categories of Heterotrophs 1. Decomposers (Saprophytes) 2. Scavengers 3. Herbivores 4. Carnivores 5. Omnivores 8
1. Decomposers Organisms that obtain its nutrients from nonliving organic matter (dead plants, dead animals) Ex: bacteria, fungi (molds, yeasts), certain plants) insects (Dung beetle), earthworms Indian Pipe (Plant) Decomposer s Role Dung Beetle Recycling Nutrients Eat dead materials to break down into chemical parts like nitrogen, carbon & other nutrients so plants & animals can use. 2. Scavengers Animals that consume (eat) already dead animals. Are carnivores. Ex: turkey vultures, crows, burying beetles, hyenas 9
Did You Know? Without decomposers and scavengers, the world would be covered with dead plants and animals! 3. Herbivores Animals that consume (eat) plants, algae, phytoplankton Deer Cow Grasshopper 4. Carnivores Carnivorous Plant: Venus Flytrap Animals which consume other animals Predators: animals which kill and consume Owl their prey Polar bears Wolf Frog Video 5. Omnivores Animals that consume both plant & animals. Raccoon Brown bear Energy Flow All organisms need energy to carry on life processes (build new cells, chemical reactions, movement) The Sun is the ultimate source of energy in ecosystems How does the energy from the Sun flow through ecosystems? 10
1. Mouse receives energy from food it eats. 2. Mouse uses energy from food to survive (growth, keep warm, capture food, escape predators). Heat is lost from body. 3. 90% of energy in mouse s food is used or lost. 10% is available for predators The Pathway of Food Energy Is Represented BY 1. Food Chains 2. Food Webs 2. Ecological Pyramids 4. Energy is lost in wastes (feces) http://magma.nationalgeographic.com/ngexplorer/0309/quickflicks/in dex.html 1. Food Chains (ENERGY FLOW) PRODUCER - a model that shows how energy moves through an ecosystem from the producer to the consumers. Primary Consumer (Herbivore) Secondary Consumer (Carnivore) SUN Describe the order of the food chain. Decomposers Tertiary Consumer (Carnivore) 2. Food Webs (ENERGY FLOW) - a complex model that shows how food chains overlap in an ecosystem. Why is the Food Web More Complex than the Food Chain? Because 1 species eats more than 1 type of organism 11
Direction of Energy Flow Return Nutrients To 3. Ecological Pyramids A pyramid that shows the transfer of energy flow using food chains. Trophic levels Energy Source Producer autotrophs Herbivore Consumer Omnivore Secondary Consumer Carnivore Tertiary Consumer Decomposer Pyramid represents the amount of: - Energy - Biomass - Numbers What Do Ecological Pyramids Tell Us? 1. Pyramid of Energy 1. Pyramid of Energy - each step (trophic level/ feeding level) up, 90% of energy is LOST because its used by organism to stay alive for cellular processes then lost by body heat. - each level passes 10% of its stored energy to next level up to make new cells. Important! Energy CAN NOT Be RECYCLED 2. Pyramid of Biomass - the total mass of living matter (weight) that is consumed by the level above it. 12
3.Pyramid of Numbers the numbers of organisms that exist at trophic levels in an ecosystem. Exercise: What Percentage of Energy is Passed Upward? Complete the Pyramid of Energy 10 Kcal 100 Kcal 1000 Kcal Does this illustration represent a Pyramid of Energy, a Pyramid of Biomass, or a Pyramid of Numbers? Birds Ants & spiders Insects & worms 1. Where is energy most abundant (in greatest amount)? Producers Pyramid of Biomass Bluegrass B. A. Identify: (Food Web, Ecological Pyramid, Food Chain) C. Summary Available food energy, biomass, & # of organisms DECREASE as you move UP the pyramid 13
A Food Chain Environmental Problem - Biomagnification - An increase concentration of pollutants along a food chain How does DDT become concentrated in the tissues of organisms at each trophic level in a food chain? DDT is metabolized & excreted more slowly & builds up in fat. Results: Organisms at the TOP of the food chain are at greatest risk. Increase concentration of DDT phytoplankton DDT inhibits the deposition of calcium DDT used on an agricultural field & rainstorm washes it into nearby stream Species declined What Are The Symbiotic Relationships In An Ecosystem? Label These Pictures: Mutualism, Commensalism, Parasitism 14
Symbiotic Relationship (Symbiosis) A close relationship between 2 species. Types of Symbiotic Relationships 1. Mutualism o 2 organisms live closely together & both benefit. Anemone protects the clownfish & gives it a safe home because the anemone has poisonous tentacles that does not harm the clownfish. Clownfish clean the anemone by eating the leftover algae & food. Also, chases away predators (butterfly fish) from the anemone Mutualism Legume nodules Other Examples: Bees & flowers (flower gets pollinated) Human intestinal bacteria (bacteria gets food, humans get vitamins) Hippos & birds (Hippo gets cleaned, birds get food & shelter) Lichen (fungus & algae) (Lichen provides a habitat for algae, algae provides food for fungus) Wrasses & cleaner shrimp (Both eat dead skin, parasites, and scrapes of food off of fish & clean mouth & gills; not harmed by the bigger fish) Nitrogen-fixing bacteria on legume nodules (bacteria live in plant roots, plants get a usable form of nitrogen in nodules to use for maintenance, bacteria gets carbohydrates (nutrient, energy) from plant via photosynthesis) Bee gets food (pollen) Flower can get pollinated because the pollen sticks to the bee s body & fertilizes it (the pollen contains the sperm cells). Bacteria gets food, human gets protection - vitamins Mutualism Mutualism Hippopotamus allows birds to prey on the parasites that feed on him even opening its mouth for bird to safely hunt. Bird has food & is safe. Hippos Hippo gets cleaned, birds get food & safety Lichens Fungus holds water for algae, algae can photosynthesize & give food to fungus 15
Cleaner shrimp & wrasse fish providing a cleaning service 2. Commensalism o One organism benefits and the other is unaffected Examples: Shark and remora (remora eats the scraps of fish from the shark without harming the shark) Epiphytes (orchids) (no roots in soil, found high in trees, doesn t get nutrients from the tree) Barnacles and whales (barnacles are crustaceans that find a home on whales to gain food, whale not harmed) Pearlfish and sea cucumbers (pearlfish s home is the anus of the sea cucumber; sea cucumber is not harmed) Lichen & tree (lichen gains more sunlight; no harm to tree) Epiphytes gets nutrients from air, falling rain, greater access to sunlight, seeds can be dispersed by wind Barnacles find their habitat on whales to find nutrients where it can be transported to new sources of food not harming the organism Shark & Remora away to obtain a food source & safety Pearlfish lives inside the anus during the day & comes out at night to search for food Lichen & tree gets sunlight, tree not harmed 3. Parasitism One organism benefits while the other is harmed Ringworm Heartworm & dogs Malaria Tapeworms Deer tick Leeches Lamprey Athlete s foot & Humans Parasites depend on host for nourishment; host weakens, gets infection, or gets ill 16
Heartworm Worm gets nutrients; Dog s heart weakens Closure: Symbiotic Relationships Lamprey gets blood; fish is wounded & could get infected Draw this table, fill in using +, -, 0 + = benefits the organism - = harms the organism 0 = organism is unaffected SPECIES A SPECIES B MUTUALISM COMMENSALISM Tapeworm gets nutrients; host is weakened PARASITISM Answers Draw this table, fill in using +, -, 0 + = benefits the organism - = harms the organism 0 = organism is unaffected SPECIES A SPECIES B MUTUALISM + + Ecological Succession COMMENSALISM + 0 PARASITISM + - Ecological Succession A change in an ecosystem where 1 community replaces another due to Bacteria, fungi, changes in abiotic & insects live off biotic factors. decaying stuff & replace it in soil A Changing Ecosystem Animals feed on plants & leaves wastes Plants grow using soil nutrients then die & return nutrients to soil 2 Types of Ecological Succession Primary Succession The development of a community in an area of rock with no topsoil Secondary Succession The return of a community to its original state after a disturbance (flood, fire, or windstorm). Soil remains & plants are the 1 st species to develop. 17
Primary Succession Pioneer species Lichens & moss secrete acids die decay material & rock make soil Yes, a community of plants 1. Does a community exists in this illustration? (grasses, flowers, shrubs, trees) 2. Which one(s) are considered the pioneer species? annual plants Forest fire, soil remains Grass, small shrubs, soil enriches Secondary Succession Grass, tall shrubs, small trees. Soil enriched Tall shrubs & trees, animals. Soil enriched 120 yrs A Pond Succession Hawaii s Primary Succession on Lava Flows Seeds flown by birds & animals debris increases & settles on bottom of pond so pondweed grows emergent plants from water grow & decay more build-up on pond floor rises marsh & animals, more debris swamp dried pond becomes forest, grassland) 1. Is This Primary or Secondary Succession? Primary 2. Why? Developed from rock 3. Prediction: What Do You Think Was The First Pioneer Species In This Picture? Lichens, Moss 18