颜色感知觉中的一个未解之谜 An Unsolved Puzzle in Color Perception 吴全丰 (Charles Q. Wu) In my previous blog “ An Unsolved Puzzle in Sound/Music Perception ”, we have encountered the issue of pitch circularity. In color perception, as a matter of fact, we have a similar, if not completely identical, puzzle -- that is, the issue of hue circularity. Physically, the “visible” (to the human eye) electromagnetic spectrum is a linear dimension, approximately ranging from 390 to 750 nm, as illustrated in Figure 1. Perceptually, however, the hues experienced by humans can be arranged in a circular manner, as illustrated in Figure 2. Doubtlessly, the transformation from a physical linear dimension to a perceptual circular variable is accomplished in the human brain. What is the brain or neural mechanism responsible for this transformation? -- This is still an unsolved puzzle in color science and neuroscience! Believe it or not, Sir Isaac Newton is the first to notice the parallel between pitch circularity in sound perception and hue circularity in color perception. Figure 3 is taken from his book “Optics” -- as you can see, he arranged seven sounds (do-re-mi-fa-so-la-ti) and his seven primary colors on the same circle. Figure 4 is a modern, colored version of Newton's color circle. Figure 1: Physical Spectrum Figure 2. CIE color map (colors are arranged in a semi-circular manner) Figure 3: Newton's original color circle Figure 4: A modern, colored version of Newton's color circle
古植物学的故事（ 126 期） 美国当代古植物学家（之五） 高产专著的古植物学家 Daniel Isaac Axelrod （ 1910--1998 ） 孙启高 2011 年 7 月 24 日 就古植物学而言，发表论文通常要比发表专著 (monograph) 要容易和实惠一些。就中国目前的学术评价体系来说，花工夫出版专著是非常吃亏的。所以，很多研究者不得不采用“短平快”的战略与战术，尽可能使自己的文章目录越长越好，但缺乏大文章 (major work) 或代表作。然而，有长期影响的古植物学专著（广义地说包括教科书）是很重要的，往往构成学科发展的基石。即便对于那些有长期影响的研究工作，我们应该坚持理性的批判精神，否则我们不可能超越前人。本期《古植物学的故事》介绍美国古植物学家 Daniel Isaac Axelrod （ 1910--1998 ），他是一位高产古植物学专著的研究者。 1910 年 7 月 10 日 Daniel Isaac Axelrod 出生于纽约布鲁克林。小时候， D. I. Axelrod 曾随家人迁居关岛、夏威夷等地。 1933 年他毕业于加州大学伯克莱分校(主修植物学)，获学士学位。 1934—1936 年供职于加州林业服务处 (The California Forest Service ) ； 1936 年从加州大学伯克莱分校获硕士学位。之后， D. I. Axelrod 师从于该校著名古植物学家 Ralph Works Chaney （ 1890—1971 ）， 1938 年从该校获得哲学博士学位。 D. I. Axelrod 的博士论文题目是“ A Miocene flora from the western border of the Mohave Desert ”，基本信息如下： Author: Axelrod, Daniel I. Title: A Miocene flora from the western border of the Mohave Desert / by Daniel I. Axelrod. Description: 192 leaves, vi leaves of plates : ill., 2 col. maps ; 28 cm. Thesis: Thesis (Ph. D. in Botany)--University of California, Berkeley, Sept. 1938. http://oskicat.berkeley.edu/record=b12388154~S1 1939—1941 年 D. I. Axelrod 在斯密松国立博物馆和卡耐基研究院从事博士后研究； 1942—1946 年服役于美军远东部队。 1946 年开始担任加州大学洛杉矶分校地质系助理教授， 1948 年担任副教授， 1952 年担地质学教授。 1962—1967 年间担任洛杉矶分校地质学与植物学教授。 1967 年， D. I. Axelrod 供职于加州大学戴维斯分校， 1976 年退休。但 D. I. Axelrod 退休后从未停止科学研究。 D. I. Axelrod 的古植物学研究特色是利用新生代植物与现代植被之间的对比研究北美西部的古环境，他的科学研究涉及植物系统学、地质学、生态学和生物地理学中的诸多问题。 D. I. Axelrod 的学术贡献主要反映在以下专著中： 1938 Miocene and Pliocene floras of western North America. 1938 A Miocene flora from the western border of the Mohave Desert / by Daniel I. Axelrod. 1938 A Miocene flora from the western border of the Mohave Desert / / by Daniel I. Axelrod. 1939 A miocene flora from the western border of the Mohave desert, by Daniel I. Axelrod. 1950 Studies in late Tertiary paleobotany. 1956 Mio-Pliocene floras from west-central Nevada. 1958 The Pliocene Verdi flora of western Nevada. 1960 Late Pliocene floras east of the Sierra Nevada, / by Daniel I. Axelrod and William S. Ting. 1961 Early pleistocene floras from the Chagoopa surface, southern Sierra Nevada, / by Daniel I. Axelrod 1962 A Pliocene Sequoiadendron forest from western Nevada. 1964 The Miocene Trapper Creek flora of southern Idaho, / by Daniel I. Axelrod. 1966 The Eocene copper basin flora of northeastern Nevada, / by Daniel I. Axelrod. 1966 The Pleistocene soboba flora of southern California, / by Daniel I. Axelrod. 1967 Evolution of the Californian closed-cone pine forest / Daniel I. Axelrod. 1967 Quaternary extinctions of large mammals, / by Daniel I. Axelrod. 1976 History of the coniferous forests, California and Nevada / by Daniel I. Axelrod 1978 Origin and relationships of the California flora / by Peter H. Raven and Daniel I. Axelrod 1979 Desert vegetation, its age and origin / Daniel I. Axelrod 1980 Contributions to the Neogene paleobotany of central California / by Daniel I. Axelrod 1980 History of the maritime closed-cone pines, Alta and Baja California / by Daniel I. Axelrod 1981 Role of volcanism in climate and evolution / Daniel I. Axelrod 1983 New Pleistocene conifer records, coastal California / by Daniel I. Axelrod. 1985 Miocene floras from the Middlegate Basin, west-central Nevada / by Daniel I. Axelrod. 1987 The late Oligocene Creede flora, Colorado / by Daniel I. Axelrod. 1991 The early Miocene Buffalo Canyon flora of western Nevada / Daniel I. Axelrod. 1992 The middle Miocene Pyramid flora of western Nevada / Daniel I. Axelrod. 1995 The Miocene Purple Mountain flora of western Nevada / Daniel I. Axelrod. 1998 The Eocene Thunder Mountain flora of central Idaho / Daniel I. Axelrod. 1998 The Oligocene Haynes Creek Flora of eastern Idaho / Daniel I. Axelrod. 2000 A Miocene (10-12 Ma) evergreen laurel-oak forest from Carmel Valley, California / Daniel I. Axelrod. 1982 年，在美国密苏里植物园举行了 “东亚温带植物和北美植物的来源关系”学术讨论会。中国派出一个学术代表团参加这次会议，成员有 汤佩松（ 1903--2001 ）、 徐仁（ 1910--1992 ）、侯学煜（ 1912--1991 ）和吴征镒（ 1916-- ）。 D. I. Axelrod 也参加了这个会议。 1998 年 6 月 2 日 D. I. Axelrod 在加州戴维斯去世，享年 88 岁。 ( 文献略 )
标签: Isaac
