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1、Introduction to The Origin of SpeciesWANG Yuguo (School of Life Sciences, Fudan University)复旦大学生命科学学院 王 玉 国物 种 起 源 导 论VARIATION UNDER NATURE自然状态下的变异CHAPTER IIVariability Individual Differences Doubtful species Wide ranging, much diffused, and common species vary most Species of the larger genera in
2、any country vary more than the species of the smaller generaMany of the species of the larger genera resemble varieties in being very closely, but unequally, related to each other, and in having restricted ranges.个体间的差异物种界定的尴尬环境对物种变异的影响大属和小属物种变异的频率Whether organic beings in a state of nature are subj
3、ect to any variation？Nor shall I here discuss the various definitions which have been given of the term species.Species Generally the term includes the unknown element of a distinct act of creation.Varieties here community of descent is almost universally implied, though it can rarely be proved.Mons
4、trosities some considerable deviation of structure in one part, either injurious to or not useful to the species, and not generally propagated.VariabilityDarwin: pigs have occasionally been born with a sort of proboscis Labuk Bay Proboscis Monkey Sanctuary Sandakan, Sabah, Malaysia If monstrous form
5、s of this kind ever do appear in a state of nature and are capable of reproduction (which is not always the case), as they occur rarely and singly, their preservation would depend on unusually favourable circumstances. Individual DifferencesThe many slight differences which appear in the offspring f
6、rom the same parents. No one supposes that all the individuals of the same species are cast in the same actual mould. These individual differences are of the highest importance for us, for they are often inherited, as must be familiar to every one; and they thus afford materials for natural selectio
7、n to act on and accumulate, in the same manner as man accumulates in any given direction individual differences in his domesticated productions. 个体间的差异These individual differences generally affect what naturalists consider unimportant parts.Authors sometimes argue in a circle when they state that im
8、portant organs never vary. It would never have been expected that the branching of the main nerves close to the great central ganglion of an insect would have been variable in the same species; it might have been thought that changes of this nature could have been effected only by slow degrees; yet
9、Sir J. Lubbock has shown a degree of variability in these main nerves in Coccus ( 介壳虫), which may almost be compared to the irregular branching of the stem of a tree. Polymorphic species or varieties?Hieracium (山柳菊属) Rubus (悬钩子属) Rosa (蔷薇属) Cicindela aurulenta (金斑虎甲) Brachiopod shells (腕足类) These fa
10、cts are very perplexing, for they seem to show that this kind of variability is independent of the conditions of life. I am inclined to suspect that we see, at least in some of these polymorphic genera, variations which are of no service or disservice to the species, and which consequently have not
11、been seized on and rendered definite by natural selection, as hereafter to be explained. 这些事实令人困惑，因为它们表现出的这些变异，似乎和生活条件无关 。我猜想，因为这些变异，至少在某些多型属内对物种本身并无利害关 系，所以自然选择既没有对它们起作用，也没有使这些特征固定下来。 对此，我将在后文再做解释。Great differences of structure, independently of variation Doubtful SpeciesTaxonomyAiluropoda melanole
12、uca1868年，法国传教士佩雷阿曼德戴维，在中国看到黑腿白熊毛皮1929年，美国西奥多和克米特罗斯福射杀了一只正在树上睡觉的大熊猫Panda可 疑 物 种Somali butcherbird? Diversity of Mussels Darwin was much struck how entirely vague and arbitrary is the distinction between species and varieties. Species or varieties？The Quercus robur(夏栎) has twenty-eight varieties, all
13、of which, excepting six, are clustered round three sub- species, namely, Q. pedunculata(有柄栎), sessiliflora(无柄花栎), and pubescens(毛栎). Cycas micholitzii叉叶苏铁 Cycas siamensis 云南苏铁Cycas panzhihuaensis 攀枝花苏铁Cycas rumphii 华南苏铁 Cycas szechuanensis 四川苏铁/南盘江苏铁Cycas hainanensis 海南苏铁Cycas angulata 角 苏 铁 Cycas g
14、uizhouensis 贵州苏铁 Cycas segmentifida 叉孢苏铁石山苏铁 Cycas miquelii 台湾苏铁 Cycas taiwaniana蓖齿苏铁 Cycas pectinata Cycas couttsiana Cycas machonie Cycas cincinalis 西米苏铁 Cycas revoluta 苏铁Ceratozamia robusta 粗壮苏铁 (墨西哥) 长籽苏铁(津巴布韦)Encephalartus manikensis Zamia integrifolia 全缘大苏铁 苏铁科，裸子植物,11属，约110种 Microcycas caloco
15、ma 小苏铁 Macrozamia moorei 摩耳大苏铁 Lepidozamia peroffskyana 东澳苏铁 大头苏铁 Encephalartos gratus 可爱苏铁Encephalartos friderici-guilielmii Dioon spinulosum 刺 苏 铁 Stangeria eriopusBowenia spectabilis Crowded Noahs Ark美国DigitalGlobe公司 “快鸟”2003年拍摄到的“亚拉腊山异物”卫星照片Mt. Ararat “诺亚方舟”长300英尺、宽50英尺，高30英尺，分为上、中、下三层。这 个尺寸是长13
16、3.29米、宽22.22米、高13.33米。方舟每层甲板的面积有 3000多平方米，约为泰坦尼克号的一半。它的总重量为1.4万吨，完全由 木头构成。宾西法尼亚州艺术家爱德华-希金 斯的画作诺亚方舟 有人认为多乌巴亚泽特是诺亚方舟的所在地 Tigers: Past and Present123虎 8个变种，3个已经绝灭巴厘虎(Balinese Tiger) 分布于印尼巴里岛 二十世纪40年代灭绝爪哇虎(Javan Tiger) 分布于印尼爪哇岛 二十世纪80年代灭绝里海虎(Caspian Tiger) 分布于土耳其至亚洲中部以及西部 二十世纪70年代灭绝123苏门达腊虎(Sumatran Tiger) 东北虎 (Siberian Tiger) 华南虎 (South China Tiger) 印支虎 (Indo-chinese Tiger) 孟加拉虎 (Panthera tigris tigris) 甲虫
