John Fox, Jr. - "The Little Shepherd of Kingdom Come"

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Annie Hamilton Donnell - "Rebecca Mary"

New Philadelphia Book Publisher Highlights Local Talent
Book and Publishing News from Publishers Newswire(tm)

Looking for Child to be on Cover of a New Book, 'The Model Child'
PHILADELPHIA, Pa. -- The Philadelphia literary world will celebrate the launch of two new players today, April 10th: Kay Square Press, a new publishing company focused on Philadelphia-area artists, their stories, and their art; and Kay Square's first release, 'With the Rich and Mighty: Emlen Etting of Philadelphia' (ISBN: 978-0-9815129-0-7), a critical biography by Kenneth C. Kaleta.

FlatSigned Press Alleges Don Imus Remarks Damage Legacy of President Gerald R. Ford
NEW YORK, N.Y. -- Nathan Yungerberg, an accomplished model scout and professional child photographer is launching a nation-wide casting call to find the cover model for his highly anticipated book release, 'The Model Child: A Parents Guide to the Child Modeling Industry' (ISBN: 978-0-9817018-0-6).

Books: On the Origin of Species

C >> Charles Darwin >> On the Origin of Species




That natural selection will always act with extreme slowness, I fully
admit. Its action depends on there being places in the polity of
nature, which can be better occupied by some of the inhabitants of the
country undergoing modification of some kind. The existence of such
places will often depend on physical changes, which are generally very
slow, and on the immigration of better adapted forms having been
checked. But the action of natural selection will probably still
oftener depend on some of the inhabitants becoming slowly modified;
the mutual relations of many of the other inhabitants being thus
disturbed. Nothing can be effected, unless favourable variations
occur, and variation itself is apparently always a very slow process.
The process will often be greatly retarded by free intercrossing. Many
will exclaim that these several causes are amply sufficient wholly to
stop the action of natural selection. I do not believe so. On the
other hand, I do believe that natural selection will always act very
slowly, often only at long intervals of time, and generally on only a
very few of the inhabitants of the same region at the same time. I
further believe, that this very slow, intermittent action of natural
selection accords perfectly well with what geology tells us of the
rate and manner at which the inhabitants of this world have changed.

Slow though the process of selection may be, if feeble man can do much
by his powers of artificial selection, I can see no limit to the
amount of change, to the beauty and infinite complexity of the
coadaptations between all organic beings, one with another and with
their physical conditions of life, which may be effected in the long
course of time by nature's power of selection.

EXTINCTION.

This subject will be more fully discussed in our chapter on Geology;
but it must be here alluded to from being intimately connected with
natural selection. Natural selection acts solely through the
preservation of variations in some way advantageous, which
consequently endure. But as from the high geometrical powers of
increase of all organic beings, each area is already fully stocked
with inhabitants, it follows that as each selected and favoured form
increases in number, so will the less favoured forms decrease and
become rare. Rarity, as geology tells us, is the precursor to
extinction. We can, also, see that any form represented by few
individuals will, during fluctuations in the seasons or in the number
of its enemies, run a good chance of utter extinction. But we may go
further than this; for as new forms are continually and slowly being
produced, unless we believe that the number of specific forms goes on
perpetually and almost indefinitely increasing, numbers inevitably
must become extinct. That the number of specific forms has not
indefinitely increased, geology shows us plainly; and indeed we can
see reason why they should not have thus increased, for the number of
places in the polity of nature is not indefinitely great,--not that we
have any means of knowing that any one region has as yet got its
maximum of species. Probably no region is as yet fully stocked, for at
the Cape of Good Hope, where more species of plants are crowded
together than in any other quarter of the world, some foreign plants
have become naturalised, without causing, as far as we know, the
extinction of any natives.

Furthermore, the species which are most numerous in individuals will
have the best chance of producing within any given period favourable
variations. We have evidence of this, in the facts given in the second
chapter, showing that it is the common species which afford the
greatest number of recorded varieties, or incipient species. Hence,
rare species will be less quickly modified or improved within any
given period, and they will consequently be beaten in the race for
life by the modified descendants of the commoner species.

From these several considerations I think it inevitably follows, that
as new species in the course of time are formed through natural
selection, others will become rarer and rarer, and finally extinct.
The forms which stand in closest competition with those undergoing
modification and improvement, will naturally suffer most. And we have
seen in the chapter on the Struggle for Existence that it is the most
closely-allied forms,--varieties of the same species, and species of
the same genus or of related genera,--which, from having nearly the
same structure, constitution, and habits, generally come into the
severest competition with each other. Consequently, each new variety
or species, during the progress of its formation, will generally press
hardest on its nearest kindred, and tend to exterminate them. We see
the same process of extermination amongst our domesticated
productions, through the selection of improved forms by man. Many
curious instances could be given showing how quickly new breeds of
cattle, sheep, and other animals, and varieties of flowers, take the
place of older and inferior kinds. In Yorkshire, it is historically
known that the ancient black cattle were displaced by the long-horns,
and that these "were swept away by the short-horns" (I quote the words
of an agricultural writer) "as if by some murderous pestilence."

DIVERGENCE OF CHARACTER.

The principle, which I have designated by this term, is of high
importance on my theory, and explains, as I believe, several important
facts. In the first place, varieties, even strongly-marked ones,
though having somewhat of the character of species--as is shown by the
hopeless doubts in many cases how to rank them--yet certainly differ
from each other far less than do good and distinct species.
Nevertheless, according to my view, varieties are species in the
process of formation, or are, as I have called them, incipient
species. How, then, does the lesser difference between varieties
become augmented into the greater difference between species? That
this does habitually happen, we must infer from most of the
innumerable species throughout nature presenting well-marked
differences; whereas varieties, the supposed prototypes and parents of
future well-marked species, present slight and ill-defined
differences. Mere chance, as we may call it, might cause one variety
to differ in some character from its parents, and the offspring of
this variety again to differ from its parent in the very same
character and in a greater degree; but this alone would never account
for so habitual and large an amount of difference as that between
varieties of the same species and species of the same genus.

As has always been my practice, let us seek light on this head from
our domestic productions. We shall here find something analogous. A
fancier is struck by a pigeon having a slightly shorter beak; another
fancier is struck by a pigeon having a rather longer beak; and on the
acknowledged principle that "fanciers do not and will not admire a
medium standard, but like extremes," they both go on (as has actually
occurred with tumbler-pigeons) choosing and breeding from birds with
longer and longer beaks, or with shorter and shorter beaks. Again, we
may suppose that at an early period one man preferred swifter horses;
another stronger and more bulky horses. The early differences would be
very slight; in the course of time, from the continued selection of
swifter horses by some breeders, and of stronger ones by others, the
differences would become greater, and would be noted as forming two
sub-breeds; finally, after the lapse of centuries, the sub-breeds
would become converted into two well-established and distinct breeds.
As the differences slowly become greater, the inferior animals with
intermediate characters, being neither very swift nor very strong,
will have been neglected, and will have tended to disappear. Here,
then, we see in man's productions the action of what may be called the
principle of divergence, causing differences, at first barely
appreciable, steadily to increase, and the breeds to diverge in
character both from each other and from their common parent.

But how, it may be asked, can any analogous principle apply in nature?
I believe it can and does apply most efficiently, from the simple
circumstance that the more diversified the descendants from any one
species become in structure, constitution, and habits, by so much will
they be better enabled to seize on many and widely diversified places
in the polity of nature, and so be enabled to increase in numbers.

We can clearly see this in the case of animals with simple habits.
Take the case of a carnivorous quadruped, of which the number that can
be supported in any country has long ago arrived at its full average.
If its natural powers of increase be allowed to act, it can succeed in
increasing (the country not undergoing any change in its conditions)
only by its varying descendants seizing on places at present occupied
by other animals: some of them, for instance, being enabled to feed on
new kinds of prey, either dead or alive; some inhabiting new stations,
climbing trees, frequenting water, and some perhaps becoming less
carnivorous. The more diversified in habits and structure the
descendants of our carnivorous animal became, the more places they
would be enabled to occupy. What applies to one animal will apply
throughout all time to all animals--that is, if they vary--for
otherwise natural selection can do nothing. So it will be with plants.
It has been experimentally proved, that if a plot of ground be sown
with one species of grass, and a similar plot be sown with several
distinct genera of grasses, a greater number of plants and a greater
weight of dry herbage can thus be raised. The same has been found to
hold good when first one variety and then several mixed varieties of
wheat have been sown on equal spaces of ground. Hence, if any one
species of grass were to go on varying, and those varieties were
continually selected which differed from each other in at all the same
manner as distinct species and genera of grasses differ from each
other, a greater number of individual plants of this species of grass,
including its modified descendants, would succeed in living on the
same piece of ground. And we well know that each species and each
variety of grass is annually sowing almost countless seeds; and thus,
as it may be said, is striving its utmost to increase its numbers.
Consequently, I cannot doubt that in the course of many thousands of
generations, the most distinct varieties of any one species of grass
would always have the best chance of succeeding and of increasing in
numbers, and thus of supplanting the less distinct varieties; and
varieties, when rendered very distinct from each other, take the rank
of species.

The truth of the principle, that the greatest amount of life can be
supported by great diversification of structure, is seen under many
natural circumstances. In an extremely small area, especially if
freely open to immigration, and where the contest between individual
and individual must be severe, we always find great diversity in its
inhabitants. For instance, I found that a piece of turf, three feet by
four in size, which had been exposed for many years to exactly the
same conditions, supported twenty species of plants, and these
belonged to eighteen genera and to eight orders, which shows how much
these plants differed from each other. So it is with the plants and
insects on small and uniform islets; and so in small ponds of fresh
water. Farmers find that they can raise most food by a rotation of
plants belonging to the most different orders: nature follows what may
be called a simultaneous rotation. Most of the animals and plants
which live close round any small piece of ground, could live on it
(supposing it not to be in any way peculiar in its nature), and may be
said to be striving to the utmost to live there; but, it is seen, that
where they come into the closest competition with each other, the
advantages of diversification of structure, with the accompanying
differences of habit and constitution, determine that the inhabitants,
which thus jostle each other most closely, shall, as a general rule,
belong to what we call different genera and orders.

The same principle is seen in the naturalisation of plants through
man's agency in foreign lands. It might have been expected that the
plants which have succeeded in becoming naturalised in any land would
generally have been closely allied to the indigenes; for these are
commonly looked at as specially created and adapted for their own
country. It might, also, perhaps have been expected that naturalised
plants would have belonged to a few groups more especially adapted to
certain stations in their new homes. But the case is very different;
and Alph. De Candolle has well remarked in his great and admirable
work, that floras gain by naturalisation, proportionally with the
number of the native genera and species, far more in new genera than
in new species. To give a single instance: in the last edition of Dr.
Asa Gray's 'Manual of the Flora of the Northern United States,' 260
naturalised plants are enumerated, and these belong to 162 genera. We
thus see that these naturalised plants are of a highly diversified
nature. They differ, moreover, to a large extent from the indigenes,
for out of the 162 genera, no less than 100 genera are not there
indigenous, and thus a large proportional addition is made to the
genera of these States.

By considering the nature of the plants or animals which have
struggled successfully with the indigenes of any country, and have
there become naturalised, we can gain some crude idea in what manner
some of the natives would have had to be modified, in order to have
gained an advantage over the other natives; and we may, I think, at
least safely infer that diversification of structure, amounting to new
generic differences, would have been profitable to them.

The advantage of diversification in the inhabitants of the same region
is, in fact, the same as that of the physiological division of labour
in the organs of the same individual body--a subject so well
elucidated by Milne Edwards. No physiologist doubts that a stomach by
being adapted to digest vegetable matter alone, or flesh alone, draws
most nutriment from these substances. So in the general economy of any
land, the more widely and perfectly the animals and plants are
diversified for different habits of life, so will a greater number of
individuals be capable of there supporting themselves. A set of
animals, with their organisation but little diversified, could hardly
compete with a set more perfectly diversified in structure. It may be
doubted, for instance, whether the Australian marsupials, which are
divided into groups differing but little from each other, and feebly
representing, as Mr. Waterhouse and others have remarked, our
carnivorous, ruminant, and rodent mammals, could successfully compete
with these well-pronounced orders. In the Australian mammals, we see
the process of diversification in an early and incomplete stage of
development. After the foregoing discussion, which ought to have been
much amplified, we may, I think, assume that the modified descendants
of any one species will succeed by so much the better as they become
more diversified in structure, and are thus enabled to encroach on
places occupied by other beings. Now let us see how this principle of
great benefit being derived from divergence of character, combined
with the principles of natural selection and of extinction, will tend
to act.

The accompanying diagram will aid us in understanding this rather
perplexing subject. Let A to L represent the species of a genus large
in its own country; these species are supposed to resemble each other
in unequal degrees, as is so generally the case in nature, and as is
represented in the diagram by the letters standing at unequal
distances. I have said a large genus, because we have seen in the
second chapter, that on an average more of the species of large genera
vary than of small genera; and the varying species of the large genera
present a greater number of varieties. We have, also, seen that the
species, which are the commonest and the most widely-diffused, vary
more than rare species with restricted ranges. Let (A) be a common,
widely-diffused, and varying species, belonging to a genus large in
its own country. The little fan of diverging dotted lines of unequal
lengths proceeding from (A), may represent its varying offspring. The
variations are supposed to be extremely slight, but of the most
diversified nature; they are not supposed all to appear
simultaneously, but often after long intervals of time; nor are they
all supposed to endure for equal periods. Only those variations which
are in some way profitable will be preserved or naturally selected.
And here the importance of the principle of benefit being derived from
divergence of character comes in; for this will generally lead to the
most different or divergent variations (represented by the outer
dotted lines) being preserved and accumulated by natural selection.
When a dotted line reaches one of the horizontal lines, and is there
marked by a small numbered letter, a sufficient amount of variation is
supposed to have been accumulated to have formed a fairly well-marked
variety, such as would be thought worthy of record in a systematic
work.

The intervals between the horizontal lines in the diagram, may
represent each a thousand generations; but it would have been better
if each had represented ten thousand generations. After a thousand
generations, species (A) is supposed to have produced two fairly
well-marked varieties, namely a1 and m1. These two varieties will
generally continue to be exposed to the same conditions which made
their parents variable, and the tendency to variability is in itself
hereditary, consequently they will tend to vary, and generally to vary
in nearly the same manner as their parents varied. Moreover, these two
varieties, being only slightly modified forms, will tend to inherit
those advantages which made their common parent (A) more numerous than
most of the other inhabitants of the same country; they will likewise
partake of those more general advantages which made the genus to which
the parent-species belonged, a large genus in its own country. And
these circumstances we know to be favourable to the production of new
varieties.

If, then, these two varieties be variable, the most divergent of their
variations will generally be preserved during the next thousand
generations. And after this interval, variety a1 is supposed in the
diagram to have produced variety a2, which will, owing to the
principle of divergence, differ more from (A) than did variety a1.
Variety m1 is supposed to have produced two varieties, namely m2 and
s2, differing from each other, and more considerably from their common
parent (A). We may continue the process by similar steps for any
length of time; some of the varieties, after each thousand
generations, producing only a single variety, but in a more and more
modified condition, some producing two or three varieties, and some
failing to produce any. Thus the varieties or modified descendants,
proceeding from the common parent (A), will generally go on increasing
in number and diverging in character. In the diagram the process is
represented up to the ten-thousandth generation, and under a condensed
and simplified form up to the fourteen-thousandth generation.

But I must here remark that I do not suppose that the process ever
goes on so regularly as is represented in the diagram, though in
itself made somewhat irregular. I am far from thinking that the most
divergent varieties will invariably prevail and multiply: a medium
form may often long endure, and may or may not produce more than one
modified descendant; for natural selection will always act according
to the nature of the places which are either unoccupied or not
perfectly occupied by other beings; and this will depend on infinitely
complex relations. But as a general rule, the more diversified in
structure the descendants from any one species can be rendered, the
more places they will be enabled to seize on, and the more their
modified progeny will be increased. In our diagram the line of
succession is broken at regular intervals by small numbered letters
marking the successive forms which have become sufficiently distinct
to be recorded as varieties. But these breaks are imaginary, and might
have been inserted anywhere, after intervals long enough to have
allowed the accumulation of a considerable amount of divergent
variation.

As all the modified descendants from a common and widely-diffused
species, belonging to a large genus, will tend to partake of the same
advantages which made their parent successful in life, they will
generally go on multiplying in number as well as diverging in
character: this is represented in the diagram by the several divergent
branches proceeding from (A). The modified offspring from the later
and more highly improved branches in the lines of descent, will, it is
probable, often take the place of, and so destroy, the earlier and
less improved branches: this is represented in the diagram by some of
the lower branches not reaching to the upper horizontal lines. In some
cases I do not doubt that the process of modification will be confined
to a single line of descent, and the number of the descendants will
not be increased; although the amount of divergent modification may
have been increased in the successive generations. This case would be
represented in the diagram, if all the lines proceeding from (A) were
removed, excepting that from a1 to a10. In the same way, for instance,
the English race-horse and English pointer have apparently both gone
on slowly diverging in character from their original stocks, without
either having given off any fresh branches or races.

After ten thousand generations, species (A) is supposed to have
produced three forms, a10, f10, and m10, which, from having diverged
in character during the successive generations, will have come to
differ largely, but perhaps unequally, from each other and from their
common parent. If we suppose the amount of change between each
horizontal line in our diagram to be excessively small, these three
forms may still be only well-marked varieties; or they may have
arrived at the doubtful category of sub-species; but we have only to
suppose the steps in the process of modification to be more numerous
or greater in amount, to convert these three forms into well-defined
species: thus the diagram illustrates the steps by which the small
differences distinguishing varieties are increased into the larger
differences distinguishing species. By continuing the same process for
a greater number of generations (as shown in the diagram in a
condensed and simplified manner), we get eight species, marked by the
letters between a14 and m14, all descended from (A). Thus, as I
believe, species are multiplied and genera are formed.

In a large genus it is probable that more than one species would vary.
In the diagram I have assumed that a second species (I) has produced,
by analogous steps, after ten thousand generations, either two
well-marked varieties (w10 and z10) or two species, according to the
amount of change supposed to be represented between the horizontal
lines. After fourteen thousand generations, six new species, marked by
the letters n14 to z14, are supposed to have been produced. In each
genus, the species, which are already extremely different in
character, will generally tend to produce the greatest number of
modified descendants; for these will have the best chance of filling
new and widely different places in the polity of nature: hence in the
diagram I have chosen the extreme species (A), and the nearly extreme
species (I), as those which have largely varied, and have given rise
to new varieties and species. The other nine species (marked by
capital letters) of our original genus, may for a long period continue
transmitting unaltered descendants; and this is shown in the diagram
by the dotted lines not prolonged far upwards from want of space.

But during the process of modification, represented in the diagram,
another of our principles, namely that of extinction, will have played
an important part. As in each fully stocked country natural selection
necessarily acts by the selected form having some advantage in the
struggle for life over other forms, there will be a constant tendency
in the improved descendants of any one species to supplant and
exterminate in each stage of descent their predecessors and their
original parent. For it should be remembered that the competition will
generally be most severe between those forms which are most nearly
related to each other in habits, constitution, and structure. Hence
all the intermediate forms between the earlier and later states, that
is between the less and more improved state of a species, as well as
the original parent-species itself, will generally tend to become
extinct. So it probably will be with many whole collateral lines of
descent, which will be conquered by later and improved lines of
descent. If, however, the modified offspring of a species get into
some distinct country, or become quickly adapted to some quite new
station, in which child and parent do not come into competition, both
may continue to exist.