Descriptive Science and Experimental Science

Descriptive Science and Experimental Science - The change...

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Descriptive Science and Experimental Science Scientists may be concerned with describing natural phenomena and they may limit their investigation to describing nature. However, they often wish to explain natural phenomena by a logical process that involves creating and testing hypotheses. Experimental Science The "Scientific Method" is a systematic approach to advancing knowledge. There are differences among scientists and among disciplines concerning the details of the method. Many of the steps involved in a typical scientific investigation are discussed below using research published on the peppered moth ( Biston betularia ). Observation There are two forms of the peppered moth ( Biston betularia) in England- a dark form and a light form. In the early 1800's, the population was almost entirely the light form. During the 1800’s the dark form increased in frequency in urban areas.
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Unformatted text preview: The change occurred at a time when increased pollution from coal fired factories darkened the trees. By 1895, 98% of the moths in Manchester were the dark form. Hypothesis A hypothesis is an explanation of an observation. In 1896, J. W. Tutt hypothesized that bird predation was responsible for the increase in abundance of the dark form of the moth. He reasoned that birds had difficulty seeing the dark form on the dark trees; the moths were camouflaged and survived better. In clean areas, the trees were covered with lichens, making the pale form more difficult for birds to see. In the early 1800s, the trees were light and the light form were more difficult to see. A hypothesis must be testable, and if false, it must be falsifiable....
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This note was uploaded on 12/15/2011 for the course BIO BSC1010 taught by Professor Gwenhauner during the Fall '10 term at Broward College.

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