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Ecology Introduction to Ecology Why are you here? Teaching children about the natural world should be treated as one of the most important events in their lives. --Thomas Berry Global and Local Environmental Issues • Human Population Growth • Water Quality and Supply – Surface – Ground • • • • • • Degradation of Soils Air Quality Species Diversity Invasive Species Land Use Post-911 Ecology Hierarchy of Biological Systems Krohne, D.T. General Ecology. 2nd Edition.Pacific Grove, CA. Brooks/Cole. 2001. p. 8 What is ecology? • Ecology – a study of the interaction between organisms and their environment. • Branches: – Molecular – Physiological – Genetic – Autoecology – Population – Community – Ecosystem* – Systems / Landscape Allied Sciences • Natural Science (qualitative descriptions) • Environmental Toxicology – chemistry and physiology of pollution • Conservation biology – maintain biodiversity • Environmental Science – ecological effects of human activities on the environment Allied Sciences • Environmental Science involves understanding: – Ecology – Chemistry – Geology – Physics – Meteorology – Cultural anthropology – Sociology – Psychology – Cartography – Economics Objectives of Ecology • Understand how the natural world works • Understand how human systems are interacting with natural systems • Accurately assess the status and model the trends of crucial natural systems • Promote and follow a long-term, sustainable relationship with the natural world Your WORLD Your CHOICE vs. Conceptual Framework for Ecological Research •Scientific Process observ e •(aka Scientific Method) –There are various ways to represent the scientific method, but all share these basic characteristics: Question Hy pothesize Research Conduct Experiments Collect and Analy ze Data Draw Conclusions Conceptual Framework for Ecological Research 1. Garbage in—Garbage out 2. All Scientific Conclusions are tentative (no vs. maybe) 3. Understanding how to do science is far more important than memorizing ephemeral facts. Conceptual Framework for Ecological Research • Science proceeds by the falsification of alternate explanations of an observed effect. (Krohne, 2001) • One of these alternative explanations (hypotheses) must be the Null Hypothesis (H0) which states that the observed effect is the result of chance (No statistically significant difference between data). Conceptual Framework for Ecological Research •Example: Do bats prefer to munch on a certain size moth? vs. Moths Conceptual Framework for Ecological Research •Observations of the bats in the field show that they prey more on big moths than little moths. Study of Bat Insectivory Frequency Conclusion? Moths Eaten 1 2 3 Moth Size Ranking 4 Conceptual Framework for Ecological Research •Now let’s gather some more data… H1= Bats prefer smaller moths Interaction of Moth Demographics and Bat Insectivory H2= Bats prefer large moths Frequency H0= Bat do not demonstrate a moth size preference Moths Present Moths eaten by bats Conclusion? 1 2 3 Moth Size Ranking 4 Reductionism vs. Holism • Reductionism – a process in which a system is reduced to its component parts for the purpose of study. • Holism – a process in which a system is kept intact for the purpose of studying the interaction of its parts. • The trick in ecological research is to be as holistic as possible while maintaining the reductionism needed to be quantitative and empirical. Reductionism vs. Holism •Example 1: Wolf predation Deer Reductionism vs. Holism •Example 2: Deer predation Wolf predation predation competition grazing Moose grazing competition grazing Hares Vegetation Reductionism vs. Holism • Most modern ecological research attempts to be as quantitative as possible. • The higher up the hierarchy you go, the more difficult it is to make inferences. • This is why comparative studies are so valuable to ecologists. Reductionism vs. Holism •Emergent Properties – Phenomena that are observable only in the complete, intact system. Statistical Analysis • Various statistical tools are useful to test the accuracy and validity of, and correlation between collected data. – Regression – T-tests – ANOVAs • Lab: Stats and Data Sets. • Discussion of Results Mathematical Modeling • Mathematical models are used in an attempt to formulate equations that reflect the operation of a system. • These models are fueled by general assumptions about the basic operation of the system that affect the validity of the final mathematical model.
