Botkin & Keller Environmental Science 5/e Chapter 2 Science as a Way of Knowing

Botkin & Keller Environmental Science 5/e Birds at Mono Lake Brine shrimp/larvae 40's: stream water diverted for drinking 20,000 acre loss in 40 yrs Scientific Info: How small and how salty? Science provided knowledge and management possibilities This was combined with values to dictate policies and actions

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Botkin & Keller Environmental Science 5/e Science as Process Science is a process of discovery –Scientific ideas change –Sometimes a science undergoes a fundamental revolution of ideas

Botkin & Keller Environmental Science 5/e Science as Process The criterion by which we decide whether a statement is in the realm of science: Whether it is possible, at least in principle, to disprove the statement.

Botkin & Keller Environmental Science 5/e Disprovability If you can think of a test that could disprove a statement, then that statement can be said to be scientific. If you can’t think of a test, then the statement is said to be nonscientific.

Botkin & Keller Environmental Science 5/e Science as Process Scientific Method: Actually a set of methods which are the systematic methods by which scientists investigate natural phenomena

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Botkin & Keller Environmental Science 5/e Crop Circles England Aliens, whirlwinds confession Denial still: –misunderstood scientific method –ignore scientific analyses and methods –both “failures” occur in environmental problems

Botkin & Keller Environmental Science 5/e Assumptions of Science Events in the natural world follow patterns that can be understood through careful observation and scientific analysis. These basic patterns and rules that describe them are the same through the universe Science is based on a type of reasoning known as induction Generalizations can be subjected to tests that may disprove them. Although new evidence can disprove existing theories, science can never provide absolute proof of the truth of its theories.

Botkin & Keller Environmental Science 5/e The Nature of Scientific Proof Deductive reasoning: –Drawing a conclusion form initial definitions and assumptions by means of logical reasoning. –Proof is absolute Inductive reasoning: –Drawing a conclusion from a limited set of specific observations. –Proof is probabalistic

Botkin & Keller Environmental Science 5/e Measurements and Uncertainty Experimental errors: –Measurement uncertainties and other errors that occur in experiments. Accuracy: –The extent to which a measurement agrees with the accepted value Precision: –The degree of exactness with which a quantity is measured

Botkin & Keller Environmental Science 5/e Observations, Facts, Inferences, and Hypotheses Observations: –The basis of science, may be made through any of the five senses or by instruments that measure beyond what we can see. Inference: –A generalization that arises from a set of observations. Fact: –When what is observed about a particular thing is agreed on by all or almost all.

Botkin & Keller Environmental Science 5/e Observations, Facts, Inferences, and Hypotheses Hypothesis: –An explanation set forth in a manner that can be tested and is capable of being disproved. Dependent variable: –A variable taken as the outcome of one or more variables. Independent variable: –The variable that is manipulated by the investigator; affects the dependent variable.

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Botkin & Keller Environmental Science 5/e Controlling Variables... In a controlled experiment, the experiment is compared to a standard (control), an exact duplicate of the experiment except for the condition of the one variable being tested (independent variable) Variables must be understood in order to be duplicated –operational definitions values of input (independent variable) and output (dependent variable) – data that is quantitative (numerical) or qualitative (nonnumerical)

Botkin & Keller Environmental Science 5/e Observations, Facts, Inferences, and Hypotheses Model: –A deliberately simplified explanation of complex phenomena. –Models are often Physical Mathematical Pictorial Computer-simulated

Botkin & Keller Environmental Science 5/e © 2008 John Wiley and Sons Publishers

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Botkin & Keller Environmental Science 5/e Observations, Facts, Inferences, and Hypotheses Theories: –Models that offer broad, fundamental explanations of many observations –Supported by a great deal of evidence –Both come from research and guide research –Discrepancies may arise and theories may be discarded and replaced with new or significantly revised theories

Botkin & Keller Environmental Science 5/e Science and Technology Science is a search for understanding, whereas technology is the application of scientific knowledge in an attempt to benefit human beings. Science often leads to technological developments, just as new technologies lead to scientific discoveries. Science is limited by the technology available.

Botkin & Keller Environmental Science 5/e Science and Objectivity Scientists do have biases and try to identify them rather than ignore them. –Best to deal with the bias by recognizing it rather than ignoring it High standards must be the “norm” or we run the danger of accepting unfounded ideas about the world –“When we confuse what we would like to believe with what we have the evidence to believe, we have a weak basis for making critical environmental decisions.”

Botkin & Keller Environmental Science 5/e Science, Pseudoscience, and Frontier Science Pseudoscience: –Some ideas presented as scientific are in fact not scientific, because they are untestable, lack empirical support, or are based on faulty reasoning or poor scientific methodology

Botkin & Keller Environmental Science 5/e © 2008 John Wiley and Sons Publishers

Botkin & Keller Environmental Science 5/e Environmental Questions and the Scientific Method Much environmental research has been limited to field observations of processes and events that have been difficult to subject to controlled experiments. Obstacles: –long time frame of many ecological processes –difficulties in setting up experimental controls in field studies –developing lab experiments of sufficient complexity

Botkin & Keller Environmental Science 5/e California Condor 1970's: 22 birds 1980's: –capture all, or half? –improve habitat? 280 condors today (139 in the wild) 2003: first wild chick Scientific understanding is essential

Botkin & Keller Environmental Science 5/e Alternatives to Direct Experimentation Historical Evidence: –Human and ecological –Boundary Waters Canoe Area (Minn.) –Showed fires to be natural and an integral part of the forest Catastrophes and Disturbances –can provide a “modern” ecological experiment –Mount St. Helens –rapid recovery –more learned when prior data is plentiful

Botkin & Keller Environmental Science 5/e Science and Decision Making Similar to scientific method –formulate a clear statement of the issue to be decided –gather the scientific information related to the issue –list alternative courses of action –predict the positive and negative consequences of each action and probability –weigh the alternative and choose the best solution

Botkin & Keller Environmental Science 5/e Learning about Science Students: –memorizing facts –lectures and texts as absolute truths –look to formulas, type problems and algorithms to solve problems Scientists: –science as the current accepted truth –subject to change –look to general principles, critical thinking, and creativity

Botkin & Keller Environmental Science 5/e Science and Media Coverage New discoveries, fringe science, pseudoscience Critical thinking is necessary –based on observations and data? –objective interpretation? –interpretation from an expert, or a subjective opinion? –media scientists