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Pearl Bracelet | Pearl Jewelry Fashion: A Renaissance in High Jewelry MakingInternational ...
Pearl Bracelet | Pearl Jewelry Fashion: A Renaissance in High Jewelry MakingInternational ...: A Renaissance in High Jewelry Making International Herald Tribune - Dec. 10, 2010 PARIS — It is taken as gospel that the king of 2...
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Starting from the thalli of marine algae to highly developed sheet
tenebricosa, we find at all levels of the contrast between internal and
the outer parts of these compacted masses of tissue; the higher Algae "the outer
the layers consist of smaller and denser cells, whereas
the inner cells of very large and sometimes very long" {p Sachs.
210.} } have the same woody leaves epidermal layer, in addition to the differences with cells
the parenchyma forming the inner part of the sheet both in size and shape
of its constituent cells by itself differentialsa thanks
the presence of solid cuticle, and due to the difference in the structure of the outer and
the inner cell partitions {83-84 Ibid.}. Particularly instructive
the structure of such intermediate types in Addition to the differentiation of peripheral
cells from the cells, prisoners inside, and in addition to the contrast between the upper and
lower surfaces of leaves Marchantiae Polymorphae clearly proves to us
direct action of random forces, and also indicates us how it is intertwined
with the action of inherited tendencies. The leaves grow from the flat
disc-shaped kidneys, the two sides are the same. She and the other side
can be top; but in the developing escape routes, put up for
the light becomes "in all circumstances the upper side which
forms stomata, the dark side becomes the bottom and produces
root hairs and leafy processes" { Ibid. 185.}. Having a clear
proof that the opposite effects of the environment on the two sides
cause differentiation, we also have proof that this process
differentiation is restricted to transferable by inheritance structure
because it is impossible to ascribe the development of stomata to the direct influence
of air and light. If we turn from leaves to stems and roots, then
meet the facts of the same value. Speaking generally of epidermal and
the inner tissue, Sachs remarks that "the contrast between them more obvious,
the more relevant part of the plant provided by the action of air and
light"{Ibid 80.}.
Above, I mentioned in passing that Darwin also took into account some
of these effects, caused directly by the organisms in the surrounding
inorganic agents. The following extract from the 6th edition
"The origin of species" quite proves it:
"It is very difficult to decide to what extent such changed conditions, as,
for example, climate, food, etc., acted in a certain direction. There
sufficient grounds to assume that over time the effects of such
your actions are much greater than us to detect a clear
evidence... Gould believes that birds of the same species are colored
much brighter, if they are living in a clearer atmosphere than those who live
near the coast or on Islands, and Wollaston is convinced that life close to
the sea acts on the coloration of insects. Mokvyn-Tandon points to the tendency
plants growing near the sea shore, have to a certain extent
fleshy leaves, although in other places they are not fleshy (p. 106-107)".
"Some observers are convinced that a damp climate causes the growth of
hair and other Horny formations" (p. 159).
In his later work "Animals and Plants under Domestication"
Darwin even more obvious recognizes these causes of change in the organization. A
the Chapter is devoted to this issue. Predosla the idea that "direct
the influence of conditions of life, whether it leads to certain results or not
matters, very special from the actions of natural selection," he
goes to the fact that the changed conditions of life "has been so definitely and
powerful on the organisation of our domesticated animals, that they were
enough to these latter formed a new subspecies
or breed without the help of human or natural selection". Here
are two of his examples:
"In the ninth Chapter I have explained in detail known to me a wonderful case
namely, that in Germany the different varieties of maize brought from hot
countries of America, have degenerated within two or three generations" (vol. II, p.
277).
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