J. S. Zerbe - "Carpentry for Boys"

Charles S. Brooks - "Journeys to Bagdad"

Ralph Bonehill - "The Boy Land Boomer"

John Foster - "An Essay on the Evils of Popular Ignorance"

Annual Bibliography of Commonwealth Literature 2007
This paper argues that discourses of love in Ghanaian market literature for youth offer a view into complex negotiations of agency and empowerment. Drawing on Deborah Durham's notion of youth as "social `shifters'" and Francis Nyamnjoh's conception of the "interconnectedness" of agency, I take Ghanaian market literature as one specific case of how African literature for youth foregrounds questions of continuity and change as African societies enter into increasingly complex global relations. In this literature for youth, received notions of love, often constructed out of impressions from American pop and hip hop music, carry new notions of agency that compete with existing "domesticated" forms. Authors like Ike Tandoh and Evelyn Tay employ discourses of love to offer youth alternative avenues for empowerment in a context of socio-economic disenfranchizement. In a creative process of "straddling", this writing both reveals and reproduces the contradictions that obtain in youth configurations of agency.

On the Genesis of Species

S >> St. George Mivart >> On the Genesis of Species




The singular order Chelonia, including the tortoises, turtles, and
terrapins (or fresh-water tortoises), is another instance of an extreme
form without any, as yet known, transitional stages. Another group may be
finally mentioned, viz. the frogs and toads, anourous Batrachians, of which
we have at present no relic of any kind linking them on to the Eft group on
the one hand, or to reptiles on the other.

The only instance in which an approach towards a series of nearly related
forms has been obtained is the existing horse, its predecessor Hipparion
and other extinct forms. But even here there is no proof whatever of
modification by minute and infinitesimal steps; _a fortiori_ no approach to
a proof of modification by "Natural Selection," acting upon indefinite
fortuitous variations. On the contrary, the series is an admirable example
of successive modification in one special direction along one beneficial
line, and the teleologist must here be allowed to consider that one {134}
motive of this modification (among probably an indefinite number of motives
inconceivable to us) was the relationship in which the horse was to stand
to the human inhabitants of this planet. These extinct forms, as Professor
Owen, remarks,[129] "differ from each other in a greater degree than do the
horse, zebra, and ass," which are not only good _zoological_ species as to
form, but are species _physiologically_, _i.e._ they cannot produce a race
of hybrids fertile _inter se_.

As to the mere action of surrounding conditions, the same Professor
remarks:[130] "Any modification affecting the density of the soil might so
far relate to the changes of limb-structure, as that a foot with a pair of
small hoofs dangling by the sides of the large one, like those behind the
cloven hoof of the ox, would cause the foot of Hipparion, _e.g._, and _a
fortiori_ the broader based three-hoofed foot of the Palaeothere, to sink
less deeply into swampy soil, and be more easily withdrawn than the more
concentratively simplified and specialized foot of the horse. Rhinoceroses
and zebras, however, tread together the arid plains of Africa in the
present day; and the horse has multiplied in that half of America where two
or more kinds of tapir still exist. That the continents of the Eocene or
Miocene periods were less diversified in respect of swamp and sward, pampas
or desert, than those of the Pliocene period, has no support from
observation or analogy."

Not only, however, do we fail to find any traces of the incipient stages of
numerous very peculiar groups of animals, but it is undeniable that there
are instances which appeared at first to indicate a _gradual transition_,
yet which instances have been shown by further investigation and discovery
not to indicate truly anything of the kind. Thus at one time the remains of
Labyrinthodonts, which up till then had been discovered, seemed to justify
the opinion that as time went on, forms had successively appeared with{135}
more and more complete segmentation and ossification of the backbone, which
in the earliest forms was (as it is in the lowest fishes now) a soft
continuous rod or notochord. Now, however, it is considered probable that
the soft back-boned Labyrinthodont Archegosaurus, was an immature or larval
form,[131] while Labyrinthodonts with completely developed vertebrae have
been found to exist amongst the very earliest forms yet discovered. The
same may be said regarding the eyes of the trilobites, some of the oldest
forms having been found as well furnished in that respect as the very last
of the group which has left its remains accessible to observation.

[Illustration: TRILOBITE.]

Such instances, however, as well as the way in which marked and special
forms (as the Pterodactyles, &c., before referred to) appear at once in and
similarly disappear from the geological record, are of course explicable on
the Darwinian theory, provided a sufficiently enormous amount of past time
be allowed. The alleged extreme, and probably great, imperfection of that
record may indeed be pleaded in excuse. But it _is_ an excuse.[132] {136}
Nor is it possible to deny the _a priori_ probability of the preservation
of at least a few _minutely transitional_ forms in some instances if
_every_ species without exception has arisen exclusively by such minute and
gradual transitions.

It remains, then, to turn to the other considerations with regard to the
relation of species to time: namely (1) as to the total amount of time
allowable by other sciences for organic evolution; and (2) the proportion
existing, on Darwinian principles, between the time anterior to the earlier
fossils, and the time since; as evidenced by the proportion between the
amount of evolutionary change during the latter epoch and that which must
have occurred anteriorly.

Sir William Thomson has lately[133] advanced arguments from three distinct
lines of inquiry, and agreeing in one approximate result. The three lines
of inquiry were--1. The action of the tides upon the earth's rotation. 2.
The probable length of time during which the sun has illuminated this
planet; and 3. The temperature of the interior of the earth. The result
arrived at by these investigations is a conclusion that the existing state
of things on the earth, life on the earth, all geological history showing
continuity of life, must be limited within some such period of past time as
one hundred million years. The first question which suggests itself,
supposing Sir W. Thomson's views to be correct, is, Is this period anything
like enough for the evolution of all organic forms by "Natural Selection"?
The second is, Is this period anything like enough for the deposition of
the strata which must have been deposited if all organic forms have been
evolved by _minute_ steps, according to the Darwinian theory?

In the first place, as to Sir William Thomson's views, the Author of this
book cannot presume to advance any opinion; but the fact that they have not
been refuted, pleads strongly in their favour when we consider how {137}
much they tell against the theory of Mr. Darwin. The last-named author only
remarks that "many of the elements in the calculation are more or less
doubtful,"[134] and Professor Huxley[135] does not attempt to _refute_ Sir
W. Thomson's arguments, but only to show cause for suspense of judgment,
inasmuch as the facts _may be_ capable of other explanations.

Mr. Wallace, on the other hand,[136] seems more disposed to accept them,
and, after considering Sir William's objections and those of Mr. Croll,
puts the probable date of the beginning of the Cambrian deposits[137] at
only twenty-four million years ago. On the other hand, he seems to consider
that specific change has been more rapid than generally supposed, and
exceptionally stable during the last score or so of thousand years.

Now, first, with regard to the time required for the evolution of all
organic forms by merely accidental, minute, and fortuitous variations, the
useful ones of which have been preserved:

Mr. Murphy[138] is distinctly of opinion that there has not been time
enough. He says, "I am inclined to think that geological time is too short
for the evolution of the higher forms of life out of the lower by that
accumulation of imperceptibly slow variations, to which alone Darwin
ascribes the whole process."

"Darwin justly mentions the greyhound as being equal to any natural species
in the perfect co-ordination of its parts, 'all adapted for extreme
fleetness and for running down weak prey.'" "Yet it is an artificial
species (and not _physiologically_ a species _at all_), formed by
long-continued selection under domestication; and there is no reason to
suppose that any of the variations which have been selected to form it have
been other than gradual and almost imperceptible. Suppose that it has {138}
taken five hundred years to form the greyhound out of his wolf-like
ancestor. This is a mere guess, but it gives the order of the magnitude."
Now, if so, "how long would it take to obtain an elephant from a protozoon,
or even from a tadpole-like fish? Ought it not to take much more than a
million times as long?"[139]

Mr. Darwin[140] would compare with the natural origin of a species
"unconscious selection, that is, the preservation of the most useful or
beautiful animals, with no intention of modifying the breed." He adds: "But
by this process of unconscious selection, various breeds have been sensibly
changed in the course of two or three centuries."

"Sensibly changed!" but not formed into "new species." Mr. Darwin, of
course, could not mean that species _generally_ change so rapidly, which
would be strangely at variance with the abundant evidence we have of the
stability of animal forms as represented on Egyptian monuments and as shown
by recent deposits. Indeed, he goes on to say,--"Species, however, probably
change much more slowly, and within the same country only a few change at
the same time. This slowness follows from all the inhabitants of the same
country being already so well adapted to each other, that places in the
polity of nature do not occur until after long intervals, when changes of
some kind in the physical conditions, or through immigration, have
occurred, and individual differences and variations of the right nature, by
which some of the inhabitants might be better fitted to their new places
under altered circumstances, might not at once occur." This is true, and
not only will these changes occur at distant intervals, but it must be
borne in mind that in tracing back an animal to a remote ancestry, we pass
through modifications of such rapidly increasing number and importance that
a geometrical progression can alone indicate the increase of periods {139}
which such profound alterations would require for their evolution through
"Natural Selection" only.

Thus let us take for an example the proboscis monkey of Borneo
(_Semnopithecus nasalis_). According to Mr. Darwin's own opinion, this form
might have been "sensibly changed" in the course of two or three centuries.
According to this, to evolve it as a true and perfect species one thousand
years would be a very moderate period. Let ten thousand years be taken to
represent approximately the period of substantially constant conditions
during which no considerable change would be brought about. Now, if one
thousand years may represent the period required for the evolution of the
species _S. nasalis_, and of the other species of the genus Semnopithecus;
ten times that period should, I think, be allowed for the differentiation
of that genus, the African Cercopithecus and the other genera of the family
Simiidae--the differences between the genera being certainly more than
tenfold greater than those between the species of the same genus. Again we
may perhaps interpose a period of ten thousand years' comparative repose.

For the differentiation of the families Simiidae and Cebidae--so very much
more distinct and different than any two genera of either family--a period
ten times greater should, I believe, be allowed than that required for the
evolution of the subordinate groups. A similarly increasing ratio should be
granted for the successive developments of the difference between the
Lemuroid and the higher forms of primates; for those between the original
primate and other root-forms of placental mammals; for those between
primary placental and implacental mammals, and perhaps also for the
divergence of the most ancient stock of these and of the monotremes, for in
all these cases modifications of structure appear to increase in complexity
in at least that ratio. Finally, a vast period must be granted for the
development of the lowest mammalian type from the primitive stock of the
whole vertebrate sub-kingdom. Supposing this primitive stock to have {140}
arisen directly from a very lowly organized animal indeed (such as a
nematoid worm, or an ascidian, or a jelly-fish), yet it is not easy to
believe that less than two thousand million years would be required for the
totality of animal development by no other means than minute, fortuitous,
occasional, and intermitting variations in all conceivable directions. If
this be even an approximation to the truth, then there seem to be strong
reasons for believing that geological time is not sufficient for such a
process.

The second question is, whether there has been time enough for the
deposition of the strata which must have been deposited, if all organic
forms have been evolved according to the Darwinian theory?

Now this may at first seem a question for geologists only, but, in fact, in
this matter geology must in some respects rather take its time from zoology
than the reverse; for if Mr. Darwin's theory be true, past time down to the
deposition of the Upper Silurian strata can have been but a very small
fraction of that during which strata have been deposited. For when those
Upper Silurian strata were formed, organic evolution had already run a
great part of its course, perhaps the longest, slowest, and most difficult
part of that course.

At that ancient epoch not only were the vertebrate, molluscous, and
arthropod types distinctly and clearly differentiated, but highly developed
forms had been produced in each of these sub-kingdoms. Thus in the
Vertebrata there were fishes not belonging to the lowest but to the very
highest groups which are known to have ever been developed, namely, the
Elasmobranchs (the highly organized sharks and rays) and the Ganoids, a
group now poorly represented, but for which the sturgeon may stand as a
type, and which in many important respects more nearly resemble higher
Vertebrata than do the ordinary or osseous fishes. Fishes in which the
ventral fins are placed in front of the pectoral ones (_i.e._ jugular
fishes) have been generally considered to be comparatively modern forms.
But Professor Huxley has kindly informed me that he has discovered a {141}
jugular fish in the Permian deposits.

Amongst the molluscous animals we have members of the very highest known
class, namely, the Cephalopods, or cuttle-fish class; and amongst
articulated animals we find Trilobites and Eurypterida, which do not belong
to any incipient worm-like group, but are distinctly differentiated
Crustacea of no low form.

[Illustration: CUTTLE-FISH.
A. Ventral aspect. B. Dorsal aspect.]

We have in all these animal types nervous systems differentiated on
distinctly different patterns, fully formed organs of circulation,
digestion, excretion, and generation, complexly constructed eyes and other
sense organs; in fact, all the most elaborate and complete animal
structures built up, and not only once, for in the fishes and mollusca we
have (as described in the third chapter of this work) the coincidence of
the independently developed organs of sense attaining a nearly similar
complexity in two quite distinct forms. If, then, so small an advance {142}
has been made in fishes, molluscs, and arthropods since the Upper Silurian
deposits, it will probably be within the mark to consider that the period
before those deposits (during which all these organs would, on the
Darwinian theory, have slowly built up their different perfections and
complexities) occupied time at least a hundredfold greater.

Now it will be a moderate computation to allow 25,000,000 years for the
deposition of the strata down to and including the Upper Silurian. If,
then, the evolutionary work done during this deposition, only represents a
hundredth part of the sum total, we shall require 2,500,000,000 (two
thousand five hundred million) years for the complete development of the
whole animal kingdom to its present state. Even one quarter of this,
however, would far exceed the time which physics and astronomy seem able to
allow for the completion of the process.

Finally, a difficulty exists as to the reason of the absence of rich
fossiliferous deposits in the oldest strata--if life was then as abundant
and varied as, on the Darwinian theory, it must have been. Mr. Darwin
himself admits[141] "the case at present must remain inexplicable; and may
be truly urged as a valid argument against the views" entertained in his
book.

Thus, then, we find a wonderful (and on Darwinian principles an all but
inexplicable) absence of minutely transitional forms. All the most marked
groups, bats, pterodactyles, chelonians, ichthyosauria, anoura, &c., appear
at once upon the scene. Even the horse, the animal whose pedigree has been
probably best preserved, affords no conclusive evidence of specific origin
by infinitesimal, fortuitous variations; while some forms, as the
labyrinthodonts and trilobites, which seemed to exhibit gradual change, are
shown by further investigation to do nothing of the sort. As regards the
time required for evolution (whether estimated by the probably minimum{143}
period required for organic change or for the deposition of strata which
accompanied that change), reasons have been suggested why it is likely that
the past history of the earth does not supply us with enough. First,
because of the prodigious increase in the importance and number of
differences and modifications which we meet with as we traverse
successively greater and more primary zoological groups; and, secondly,
because of the vast series of strata necessarily deposited if the period
since the Lower Silurian marks but a small fraction of the period of
organic evolution. Finally, the absence or rarity of fossils in the oldest
rocks is a point at present inexplicable, and not to be forgotten or
neglected.

Now all these difficulties are avoided if we admit that new forms of animal
life of all degrees of complexity appear from time to time with comparative
suddenness, being evolved according to laws in part depending on
surrounding conditions, in part internal--similar to the way in which
crystals (and, perhaps from recent researches, the lowest forms of life)
build themselves up according to the internal laws of their component
substance, and in harmony and correspondence with all environing influences
and conditions. [Page 144]

* * * * *


CHAPTER VII.

SPECIES AND SPACE.

The geographical distribution of animals presents difficulties.--These
not insurmountable in themselves; harmonize with other
difficulties.--Fresh-water fishes.--Forms common to Africa and India;
to Africa and South America; to China and Australia; to North America
and China; to New Zealand and South America; to South America and
Tasmania; to South America and Australia.--Pleurodont
lizards.--Insectivorous mammals.--Similarity of European and South
American frogs--Analogy between European salmon and fishes of New
Zealand, &c. An ancient Antarctic continent probable.--Other modes of
accounting for facts of distribution.--Independent origin of closely
similar forms.--Conclusion.

The study of the distribution of animals over the earth's surface presents
us with many facts having certain not unimportant bearings on the question
of specific origin. Amongst these are instances which, at least at first
sight, appear to conflict with the Darwinian theory of "Natural Selection."
It is not, however, here contended that such facts do by any means
constitute by themselves obstacles which cannot be got over. Indeed it
would be difficult to imagine any obstacles of the kind which could not be
surmounted by an indefinite number of terrestrial modifications of
surface--submergences and emergences--junctions and separations of
continents in all directions and combinations of any desired degree of
frequency. All this being supplemented by the intercalation of armies of
enemies, multitudes of ancestors of all kinds, and myriads of connecting
forms, whose _raison d'etre_ may be simply their utility or necessity {145}
for the support of the theory of "Natural Selection."

Nevertheless, when brought in merely to supplement and accentuate
considerations and arguments derived from other sources, in that case
difficulties connected with the geographical distribution of animals are
not without significance, and are worthy of mention even though, by
themselves, they constitute but feeble and more or less easily explicable
puzzles which could not alone suffice either to sustain or to defeat any
theory of specific origination.

Many facts as to the present distribution of animal life over the world are
very readily explicable by the hypothesis of slight elevations and
depressions of larger and smaller parts of its surface, but there are
others the existence of which it is much more difficult so to explain.

The distribution either of animals possessing the power of flight, or of
inhabitants of the ocean, is, of course, easily to be accounted for; the
difficulty, if there is really any, must mainly be with strictly
terrestrial animals of moderate or small powers of locomotion and with
inhabitants of fresh water. Mr. Darwin himself observes,[142] "In regard to
fish, I believe that the same species never occur in the fresh waters of
distant continents." Now, the Author is enabled, by the labours and through
the kindness of Dr. Guenther, to show that this belief cannot be maintained;
he having been so obliging as to call attention to the following facts with
regard to fish-distribution. These facts show that though only one species
which is absolutely and exclusively an inhabitant of fresh water is as yet
known to be found in distant continents, yet that in several other
instances the same species _is_ found in the fresh water of distant
continents, and that very often the same _genus_ is so distributed.

The genus _Mastacembelus_ belongs to a family of fresh-water Indian {146}
fishes. Eight species of this genus are described by Dr. Guenther in his
catalogue.[143] These forms extend from Java and Borneo on the one hand, to
Aleppo on the other. Nevertheless, a new species (_M. cryptacanthus_) has
been described by the same author,[144] which is an inhabitant of the
Camaroon country of _Western_ Africa. He observes, "The occurrence of
Indian forms on the West Coast of Africa, such as _Periophthalmus_,
_Psettus_, _Mastacembelus_, is of the highest interest, and an almost new
fact in our knowledge of the geographical distribution of fishes."

_Ophiocephalus_, again, is a truly Indian genus, there being no less than
twenty-five species,[145] all from the fresh waters of the East Indies. Yet
Dr. Guenther informs me that there is a species in the Upper Nile and in
West Africa.

The acanthopterygian family (_Labyrinthici_) contains nine freshwater
genera, and these are distributed between the East Indies and South and
Central Africa.

The Carp fishes (Cyprinoids) are found in India, Africa, and Madagascar,
but there are none in South America.

Thus existing fresh-water fishes point to an immediate connexion between
Africa and India, harmonizing with what we learn from Miocene mammalian
remains.

On the other hand, the Characinidae (a family of the physostomous fishes)
are found in Africa and South America, and not in India, and even its
component groups are so distributed,--namely, the _Tetragonopterina_[146]
and the _Hydrocyonina_.[147]

Again, we have similar phenomena in that almost exclusively fresh-water
group the Siluroids.

Thus the genera _Clarias_[148] and _Heterobranchus_[149] are found {147}
both in Africa and the East Indies. _Plotosus_ is found in Africa, India,
and Australia, and the species _P. anguillaris_[150] has been brought from
both China and Moreton Bay. Here, therefore, we have the same species in
two distinct geographical regions. It is however a coast fish, which,
though entering rivers, yet lives in the sea.

_Eutropius_[151] is an African genus, but _E. obtusirostris_ comes from
India. On the other hand, _Amiurus_ is a North American form; but one
species, _A. cantonensis_,[152] comes from China.

The genus _Galaxias_[153] has at least one species common to New Zealand
and South America, and one common to South America and Tasmania. In this
genus we thus have an absolutely and completely fresh-water form _of the
very same species_ distributed between different and distinct geographical
regions.

Of the lower fishes, a lamprey, _Mordacia mordax_,[154] is common to South
Australia and Chile; while another form of the same family, namely,
_Geotria chilensis_,[155] is found not only in South America and Australia,
but in New Zealand also. These fishes, however, probably pass part of their
lives in the sea.

We thus certainly have several species which _are_ common to the fresh
waters of distant continents, although it cannot be certainly affirmed that
they are exclusively and entirely fresh-water fishes throughout all their
lives except in the case of _Galaxias_.

Existing forms point to a close union between South America and Africa on
the one hand, and between South America, Australia, Tasmania, and New
Zealand on the other; but these unions were not synchronous any more than
the unions indicated between India and Australia, China and Australia,
China and North America, and India and Africa.

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