Ecology - 10 Questions Outline Principles of Ecology 1. What is ecology? 2. What is a population? 3. What is a community? 4. What is an ecosystem? 5. What is a biome? 6. What is the biosphere? 7. What is a food chain? 8. What is trophic structure and what are consumers, producers & detritivores 9. What ecological issues face us? Definition of ecology Hierarchy of relationships Populations Communities Ecosystems & Biomes Biosphere Ecosystems & Energy Flow Populations & Exponential Growth 1 2 Ecology Population Survivorship Curves Interactions of living organisms with each other and their physical environment. Distribution and abundance 3 4
Population Pyramids United States: Shifting Population Pyramids 5 6 Ecological Footprints Ecological/Biological Communities 7 8
Biological Communities Community = all the species that occur together in a place. 1. Live together 2. Evolve together Competition & Cooperation 3. Achieve stability Community Ecology - Habitat and Niche Habitat is the place where an organism lives. Niche = the total of all ways a species utilizes the resources of its environment. 9 10 Community Ecology - Predation Predation One organism consumes another. A selection pressure Effect on Prey favors characteristics in prey that decrease the probability of capture. increased fitness of prey. Community Ecology - Plant Defenses Against Herbivores Morphological thorns, spines Effect on Predator favors characteristics in predator that increase probability of prey capture. increased fitness of predator. Chemical secondary chemical compounds Mustard oils, cardiac glycosides 11 12
Animal Defenses Against Predators Chemical defenses poisons and stings Defensive coloration Warning coloration = aposematic coloration individuals advertise poisonous nature Camouflage coloration = cryptic coloration Animal Defenses Against Predators Monarch caterpillars eat milkweed plants Some animals benefit from plant toxic secondary compounds Monarch butterfly Viceroy butterfly 13 14 Community Succession 15 16
Ecological Community Succession Succession = change in species composition over time Characteristics of Succession Unstable Pioneer Communities Simple Communities High biotic potential Don t compete well Stable Climax Communities Complex Communities Low biotic potential Compete well 17 18 Biomes Ecosystem
Biome Large Ecosystem Rainforest warm & high moisture Major terrestrial biomes Savanna dry, warm seasonal moisture Desert very little moisture Tundra treeless, permafrost 30ºN Tropic of Cancer Equator Tropic of Capricorn 30ºS Tropical forest Savanna Desert Chaparral Temperate grassland Temperate broadleaf forest Coniferous forest Tundra High mountains Polar ice 22 Biomes Mean annual Temperature (C) Biosphere Mean annual Precipitation (cm)
Ecosystem Food Chains & Trophic Levels Trophic level 4 Trophic level 3 Trophic level 2 Trophic level 1 Top carnivore Tertiary consumer Carnivore Secondary consumer Herbivore Primary consumer Photosynthesizer Producers Detritivores decomposers Fungi & Bacteria CONNECTION Production pyramid explains why meat is a luxury Field of corn Supports many more herbivores than carnivores. Trophic level Secondary consumers Primary consumers Producers Other Humans Human vegetarians Human meat-eaters Ecosystem Calorie Counting 10,000 1 10 100 Copyright 2005 Pearson Education, Inc. Publishing as Benjamin Cummings Serious Ecological Problems Rainforest Destruction Loss of Biodiversity Biological Magnification heavy metals, PCBs, dioxins Ozone depletion from Fluorocarbons Acid Rain from Sulfur dioxide Global Warming from Greenhouse Gases Population Growth END Introduction to Ecology 27 28