It is a truly wonderful fact— the wonder of which we are apt to overlook from familiarity— that all animals and all plants throughout all time and space should be related to each other in
group group 1859 1860 1861 1866 | natural groups 1869 | groups 1872 |
subordinate to
group, group, 1859 1860 1861 1866 | groups, 1869 1872 |
in the manner which we everywhere behold— namely, varieties of the same species most closely
related related 1859 1860 1861 1866 1869 | related, 1872 |
together, together, 1859 1860 1861 1866 1869 | together, 1872 |
species of the same genus less closely and unequally
related related 1859 1860 1861 1866 1869 | related, 1872 |
together, together, 1859 1860 1861 1866 1869 | together, 1872 |
forming sections and sub-genera, species of distinct genera much less closely related, and genera related in different degrees, forming sub-families,
families, orders, sub-classes, and classes. The several subordinate groups in any class cannot be ranked in a single file, but seem
rather to be rather to be 1859 1860 1861 1866 1869 |
OMIT 1872 |
clustered round points, and these round other points, and so on in almost endless cycles.
On the view that each species has On the view that each species has 1859 1860 1861 1866 |
If each species has 1869 |
If species had 1872 |
been independently created,
I can see I can see 1859 1860 1861 1866 |
OMIT 1869 1872 |
no explanation
of this great fact in the classification of all organic beings; but, to the best of my judgment, of this great fact in the classification of all organic beings; but, to the best of my judgment, 1859 1860 1861 1866 |
can be given of this great fact in the classification of all organic beings; but 1869 |
would have been possible of this kind of classification; but 1872 |
it is explained through inheritance and the complex action of natural selection, entailing extinction and divergence of character, as we have seen illustrated in the diagram. |
The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth. The green and budding twigs may represent existing species; and those produced during
each each 1859 1860 1861 1866 | each 1869 1872 |
former
year year 1859 1860 1861 1866 | years 1869 1872 |
may represent the long succession of extinct species. At each period of growth all the growing twigs have tried to branch out on all sides, and to overtop and kill the surrounding twigs and branches, in the same manner as species and groups of species have
tried to tried to 1859 1860 1861 1866 |
at all times 1869 1872 |
overmaster overmaster 1859 1860 1861 1866 | overmastered 1869 1872 |
other species in the great battle for life. The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was
small, small, 1859 1860 1861 1866 1869 | young, 1872 |
budding twigs; and this
connexion connexion 1859 1860 1861 1866 | connection 1869 1872 |
of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups. Of the many twigs which flourished when the tree was a mere bush, only two or three, now grown into great branches, yet survive and bear
all all 1859 1860 1861 1866 1869 | all 1872 |
the other branches; so with the species which lived during long-past geological periods, very few
now now 1859 1860 1861 1866 1869 | now 1872 |
have
living living 1859 1860 1861 1866 1869 | left living 1872 |
and modified descendants. From the first growth of the tree, many a limb and branch has decayed and dropped off; and these
lost lost 1859 1860 1861 1866 1869 | fallen 1872 |
branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only
from being found from being found 1866 1869 |
from having been found 1859 1860 1861 |
OMIT 1872 |
in a fossil state. As we here and there see a thin straggling branch springing from a fork low down in a tree, and which by some chance has been favoured and is still alive on its summit, so we
|