History Weblecture for Unit 57
|This Unit's||Homework Page||History Lecture||Science Lecture||Lab||Parents' Notes|
For the interactive timelines, click on an image to bring it into focus and read notes.
Click on the icon to bring up the timeline in a separate browser window. You can then resize the window to make it easier to read the information.
Click here: Timeline PDF to bring up the timeline as a PDF document. You can then click on the individual events to see more information if you want. Exploring this version of the timeline is optional!
The two major advances in biology during the twentieth century have both emphasized the common features which characterize all life on earth. This week, we look at the developing concept of the environment and our growing realization that not only do most living things interact with the environment and each other, they are also interdependent. Over the next three weeks, we will look at the discoveries of the processes of photosynthesis, cellular respiration, and cell reproduction, working our way from the large context of the interaction of populations of individual organisms with their environment and each other to the details of individual molecules.
When the first Europeans came to the American continent, they saw the wilderness in many different ways. For some, both the wilderness and the native Americans were untouched by the corrupting civilization of the Old World, and should be carefully studied. For others, the wilderness was the abode of evil, to be tamed and civilized. And for still others, it was neither particularly good or bad, but full of endless resources to be used without fear of shortage.
During the nineteenth centuries, explorers and settlers realized that their infiltration into the wilderness was changing it and, in some areas, destroying it. Attitudes toward the wilderness changed, and people became interested in at least recording the passing of the frontier. The naturalist worked as a collector and observer of nature in the field. Often working outside the academic professions or labs, many naturalists had a difficult time winning recognition of the scientific value of their observations.
The art works of John James Audubon brought the beauty of America's birds to its urban East Coast and to Europe--but Audubon was not seriously concerned with conservation efforts until near the end of his life. He found the birds and mammals of the new world curious, fascinating, and well worth drawing.
Read about John James Audubon at the Audubon Society's Web Page [1 brief web page (biography)]. Then read the more detailed description of Audubon's work in Florida (with illustrations) at the Historical Museum of Southern Florida. [10 very short web pages with graphics (Birds of America)]
[If the Audubon site pages are not unavailable, take a look at the New World Encyclopedia article.]
In contrast, the explorer John Muir not only recognized the beauty of the wilderness, but, like Henry David Thoreau, felt that mankind needed the wilderness as a source of spiritual renewal. It is largely to Muir that we owe the idea of the National Park system and the creation of Yosemite National Park. Muir was an enthusiastic conservationist who was able to communicate his concerns and dreams to those around him, and eventually founded the Sierra Club.
Muir's ideas were in marked contrast to those of conservationists like Gifford Pinchot, who believed that natural areas should be maintained to ensure a steady supply of their resources (such as lumber) for posterity. Both Pinchot and Muir opposed the unregulated use of wilderness resources without any thought for their restoration or the needs of future generations. But neither realized how complex the interrelationship of life on the planet could become....or that efforts to control one small area of nature could devastate others.
During the fourth decade of this century, the entire world suffered economic upheaval and famine. In the United States, the Great Depression was fueled in part by the dust storms in the midwest, which destroyed crops and removed topsoil from America's richest farmland. After the climate returned to something approaching normal, and the nation had survived war on two fronts, American farmers worked hard to restore their farms and the country to prosperity. The new techniques they used to increase crop yield included spraying plants with DDT (fresh from its war use of ridding soldiers of lice) to kill insect pests. Often, spraying was done by low-flying planes, and the poison fell not only on the plants, but on the ground, surrounding vegetation, all insects (not just the pests) and animals living in the area, and found its way into the water supply.
Rachel Carson was among those to voice her concern that widespread use of insecticides killed birds and bees as well as lice and mosquitoes--and that perhaps killing off all the mosquitoes was not such a good idea. S Her book, Silent Spring, published in 1962, forced the nation to reconsider its policies.
Carson's book represents a new attitude toward nature and man in it. She viewed humans as but one part of the web of life which related all living organisms, perhaps with no more right to be on the planet than ants or Douglas fir trees, but certainly--because of their minds and abilities, with the responsibility for choosing their activities carefully.
© 2005 - 2019 This course is offered through Scholars Online, a non-profit organization supporting classical Christian education through online courses. Permission to copy course content (lessons and labs) for personal study is granted to students currently or formerly enrolled in the course through Scholars Online. Reproduction for any other purpose, without the express written consent of the author, is prohibited.