{"id":87,"date":"2021-01-25T00:56:06","date_gmt":"2021-01-25T00:56:06","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-hccc-generalscience\/?post_type=chapter&p=87"},"modified":"2021-01-25T00:56:06","modified_gmt":"2021-01-25T00:56:06","slug":"5-comparison-in-scientific-research","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-hccc-generalscience\/chapter\/5-comparison-in-scientific-research\/","title":{"raw":"5. Comparison in Scientific Research","rendered":"5. Comparison in Scientific Research"},"content":{"raw":"
\r\n\r\nnyone who has stared at a chimpanzee in a zoo (Figure 1) has probably wondered about the animal's similarity to humans. Chimps make facial expressions that resemble humans, use their hands in much the same way we do, are adept at using different objects as tools, and even laugh when they are tickled. It may not be surprising to learn then that when the first captured chimpanzees were brought to Europe in the 17th<\/sup> century, people were confused, labeling the animals \"pygmies\" and speculating that they were stunted versions of \"full-grown\" humans. A London physician named Edward Tyson<\/a> obtained a \"pygmie\" that had died of an infection shortly after arriving in London, and began a systematic study of the animal that cataloged the differences between chimpanzees and humans, thus helping to establish comparative<\/a> research<\/a> as a scientific method<\/a>.\r\n
\"chimpanzee\"
Figure 1: A chimpanzee image \u00a9 Corel Corporation<\/span><\/figcaption><\/figure>\r\n<\/div>\r\n
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A brief history of comparative methods<\/h2>\r\nIn 1698, Tyson, a member of the Royal Society of London, began a detailed dissection of the \"pygmie\" he had obtained and published his findings in the 1699 work: Orang-Outang, sive Homo Sylvestris: or, the Anatomy of a Pygmie Compared with that of a Monkey, an Ape, and a Man<\/em>. The title of the work further reflects the misconception that existed at the time \u2013 Tyson did not use the term Orang-Outang in its modern sense to refer to the orangutan; he used it in its literal translation from the Malay language as \"man of the woods,\" as that is how the chimps were viewed.\r\n\r\nTyson took great care in his dissection. He precisely measured and compared a number of anatomical variables<\/a> such as brain size of the \"pygmie,\" ape, and human. He recorded his measurements of the \"pygmie,\" even down to the direction in which the animal's hair grew: \"The tendency of the Hair of all of the Body was downwards; but only from the Wrists to the Elbows 'twas upwards\" (Russell, 1967). Aided by William Cowper, Tyson made drawings of various anatomical structures, taking great care to accurately depict the dimensions of these structures so that they could be compared to those in humans (Figure 2). His systematic comparative<\/a> study of the dimensions of anatomical structures in the chimp, ape, and human led him to state:\r\n
in the Organization of abundance of its Parts, it more approached to the Structure of the same in Men: But where it differs from a Man, there it resembles plainly the Common Ape, more than any other Animal. (Russell, 1967)<\/blockquote>\r\nTyson's comparative<\/a> studies proved exceptionally accurate and his research<\/a> was used by others, including Thomas Henry Huxley<\/a> in Evidence as to Man's Place in Nature<\/em> (1863) and Charles Darwin<\/a> in The Descent of Man<\/em> (1871).\r\n
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Figure 2: Edward Tyson's drawing of the external appearance of a \"pygmie\" (left) and the animal's skeleton (right) from The Anatomy of a Pygmie Compared with that of a Monkey, an Ape, and a Man<\/em> from the second edition, London, printed for T. Osborne, 1751.<\/figcaption><\/figure>\r\nTyson's methodical and scientific approach to anatomical dissection contributed to the development of evolutionary theory<\/a> and helped establish the field of comparative<\/a> anatomy. Further, Tyson's work helps to highlight the importance of comparison as a scientific research<\/a> method<\/a>.\r\n\r\n<\/section>
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Comparison as a scientific research method<\/h2>\r\nComparative research<\/a> represents one approach in the spectrum of scientific research methods<\/a> and in some ways is a hybrid of other methods, drawing on aspects of both experimental science (see our Experimentation in Science<\/a> module) and descriptive research (see our Description in Science<\/a> module). Similar to experimentation, comparison seeks to decipher the relationship between two or more variables<\/a> by documenting observed differences and similarities between two or more subjects<\/a> or groups. In contrast to experimentation, the comparative<\/a> researcher does not subject one of those groups to a treatment<\/a>, but rather observes a group that either by choice or circumstance has been subject to a treatment. Thus comparison involves observation<\/a> in a more \"natural\" setting, not subject to experimental confines, and in this way evokes similarities with description.\r\n\r\nImportantly, the simple comparison of two variables<\/a> or objects is not comparative<\/a> research<\/a>. Tyson's work would not have been considered scientific research if he had simply noted that \"pygmies\" looked like humans without measuring bone lengths and hair growth patterns. Instead, comparative research involves the systematic cataloging of the nature and\/or behavior of two or more variables, and the quantification of the relationship between them.\r\n
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Figure 3: Skeleton of the juvenile chimpanzee dissected by Edward Tyson, currently displayed at the Natural History Museum, London. image \u00a9 Peter Kaminski<\/span><\/figcaption><\/figure>\r\nWhile the choice of which research<\/a> method<\/a> to use is a personal decision based in part on the training of the researchers conducting the study, there are a number of scenarios in which comparative<\/a> research would likely be the primary choice.\r\n
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