History of Theories of Mass Extinction by Meteorite Impact and Alternative Causes

威廉·格伦博士，谁是根据该项目进行 Weart博士的指导下，继续他的研究，支持下， 以前的NSF赠款，一系列当前的跨学科 化学证据的发现引发的争论 这表明在大规模灭绝时发生了陨石撞击， 6500万年前的化石记录。 这样的预防措施， 后来假定为周期性，解释了三个新的 其他天文学假设，都是为了周期性地 使地球充满彗星。 一些额外的假设 也提出了解决的各个方面， 生物圈、大气圈和岩石圈对质量的影响 注意事项 Glen博士制作了一个特定阶段的数据库， 大量参与者的口述历史访谈， 对这些相互竞争的理论的发展的争论。 这些访谈和其他文件资料有助于 理解感知如何随着论点的演变而形成和改变。 它们还用于评估各种科学模型， 对这场剧变进行了分析和分类 这些争论的结果。 原始史料的采访与收集 已经基本完成。 格伦博士目前正在完成 对9个专业协会的成员进行了一项重大调查， 正在讨论的理论。 在这项资助下，他正在分析 他收集到的数据，进行了一些重点跟踪， 采访，研究这些辩论的“前历史”， 准备对这段历史进行最后的研究。 这些结果，当 出版，将为历史提供主要的原始资料， 科学哲学社会科学。

Dr. William Glen, who is undertaking this project under the direction of Dr. Weart, is continuing his study, supported under previous NSF grants, of a series of current interdisciplinary debates that were prompted by the discovery of chemical evidence suggesting a meteorite impact at the time of mass extinction in the fossil record 65 million years ago. Such extinctions, subsequently postulated as periodic, were explained by three new alternative astronomical hypotheses, all designed to cyclically shower the earth with comets. A number of additional hypotheses have also been advanced that address various aspects of the biosphere, atmosphere, and lithosphere bearing on mass extinctions. Dr. Glen has produced a stage-specific data base including a large number of oral history interviews of the participants of the debates over the development of these competing theories. These interviews and other documentary data have aided in understanding how perceptions form and alter as arguments evolve. They also serve in assessing various models of science and have lent themselves to the analysis and taxonomy of the upheaval resulting from these debates. The interviewing and collecting of primary historical materials has been essentially completed. Dr. Glen is currently completing a major survey of members of 9 professional societies related to the theories under debate. Under this grant, he is analyzing the data he has collected to date, conducting a few focussed followup interviews, examining the "pre-history" of these debates, and preparing a final study of this history. These results, when published, will provide major source material for the history, philosophy and social science of science.