GeneticaJohannes Paulus Lotsy, Marius Jacob Sirks, Havik Nicolaas Kooiman W. Junk, 1927 Includes section "Boekbesprekingen." |
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Anzahl appendices Axil spot beiden bistortata Blätter Blüten Blütenfarbe Bolters per 1000 catacorolla characters CHIG chromosomes corolla crepuscularia Cross 23 crossing-over dasz diploid double flowers double-flowered drei einige F₁ F₂ F₂-Generationen factors Faktoren Familien Farbe forms Friesland Frisian gametic Geburten Geburtspausen Geburtsperiodizität genetic Genetica genotypically Geschlechte gibt habe haploid homozygous hybrid Individuen Jahr Kedoe können konstant Kreuzung Kreuzungen Kultur Kulturen Lb Lb leaf linkage Loganberry magenta flower meistens melanic Monate Monaten motherplant Nektarien Nigella Nigella damascena normal normalen occur Orchis parent parthenogenesis Pflanze Pflanzen plants pollen pollinia prickles races relative value RSITY rusticanus Samen schon seedlings seeds segregation Seitenäste Selbstung Selbstungen sind SITY slender species Stamm TABLE Teil tendency to connation tetraploid text figures thyrsiger tion ungefähr UNIV UNIV Unterschied Unterschiede variation verschiedene viel Wageningen weiter weniger white margin wurde wurden Zahl Zahlen zeigt ziemlich zijn Zusam zwei
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Стр. 289 - I may take this opportunity of remarking that my critics frequently assume that I attribute all changes of corporeal structure and mental power exclusively to the natural selection of such variations as are often called spontaneous; whereas, even in the first edition of the
Стр. 290 - We have now seen that the external characteristic differences between the races of man cannot be accounted for in a satisfactory manner by the direct action of the conditions of life, nor by the effects of the continued use of parts, nor through the principle of correlation.
Стр. 290 - We have thus far been baffled in all our attempts to account for the differences between the races of man ; but there remains one important agency, namely Sexual Selection, which appears to have acted as powerfully on man, as on many other animals. I do not intend to assert that sexual selection will account for all the differences between the races.
Стр. 290 - The great variability of all the external differences between the races of man, likewise indicates that they cannot be of much importance; for if important, they would long ago have been either fixed and preserved or eliminated. In this respect man resembles those forms, called by naturalists protean or polymorphic, which have remained extremely variable, owing, as it seems, to such variations being of an indifferent nature, and to their having thus escaped the action of natural selection.
Стр. 302 - Natural Selection acts exclusively by the preservation and accumulation of variations, which are beneficial under the organic and inorganic conditions to which each creature is exposed at all periods of life. The ultimate result is that each creature tends to become more and more improved in relation to its conditions. This improvement inevitably leads to the gradual advancement of the organisation of the greater number of living beings throughout the world.
Стр. 289 - Some allowance, too, must be made for occasional reversions of structure; nor must we forget what I have called "correlated" growth, meaning, thereby, that various parts of the organisation are in some unknown manner so connected, that when one part varies, so do others; and if variations in the one are accumulated by selection, other parts will be modified. Again, it has been said by several critics, that when I found that many details of structure in man could not be explained through natural selection,...
Стр. 322 - ... which protruded forward, so as to form an unbroken curve of neck and back, in place of the alternation of curves which is one of the graces of the truly erect Homo sapiens. The heavy overhanging eyebrow-ridges, and retreating forehead, the great coarse face with its large eye-sockets, broad nose, and receding chin, combined to complete the picture of unattractiveness, which it is more probable than not was still further emphasized by a shaggy covering of hair over most of the body. The arms were...
Стр. 291 - ... surprising how little effect he produced by cultivating certain plants under unnatural conditions, as the presence of salt, lime, zinc, &c., &c., during several generations. Plants, moreover, were selected which were the most likely to vary under such conditions, judging from the existence of closely-allied forms adapted for these conditions. No doubt I originally attributed too little weight to the direct action of conditions, but Hoffmann's paper has staggered me. Perhaps hundreds of generations...
Стр. 291 - When I view all beings not as special creations, but as the lineal descendants of some few beings which lived long before the first bed of the Cambrian system was deposited, they seem to me to become ennobled.
Стр. 311 - ... Western Europe, have so far been recovered, to give us some slight clues as to what was happening in the really vital spot. The vast geographical area that separates Java from Europe, and the incalculable span of time that intervened between the epochs of Pithecanthropus and the fossil men of Europe, represent a tremendous hiatus in the early history of the Human Family. Behind the veil of all these hidden centuries, it is well within the bounds of reasonable conjecture to picture the wide stretch...