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Speciation Conference
Brings Good News for Creationists
First published in: Creation
Ex Nihilo Technical Journal 11(2):135-136, 1997
Poorly-informed anti-creationist scoffers occasionally
think they will 'floor' creation apologists with examples of 'new species
forming' in nature. They are often surprised at the reaction they get from
the better-informed creationists, namely that the creation model depends
heavily on speciation.
It seems clear that some of the groupings above species
(for example, genera, and sometimes higher up the hierarchy) are almost
certainly linked by common ancestry, that is, are the descendants of one
created ancestral population (the created kind, or baramin).
Virtually all creation theorists assume that Noah did not have with him
pairs of dingoes, wolves and coyotes, for example, but a pair of creatures
which were ancestral to all these species, and probably to a number of
other present-day species representative of the 'dog kind'.
Demonstrating that speciation can happen in nature,
especially where it can be shown to have happened rapidly, is thus a
positive for creation theorists. A commonly heard objection is that,
surely, speciation is evolution, and that the creationists are postulating
even more rapid post-Flood evolution than evolutionists do! In reply, it
should be pointed out that the difference is all about genetic
information. The 'big picture' of evolution is that protozoa have
become pelicans, palm trees and people. Thus it must have involved
processes which, via natural causes, increased the genetic information in
the biosphere.
The creationist assumes that real, substantive increases
in information (that is, specifying for an increase in what might be
called 'functional complexity') will never arise without intelligent
cause. Speciation within the creationist model will therefore be expected
to occur in the absence of any increases in the information within the
biosphere, and thus can properly be classified as non-evolutionary.
Of course, such changes (for example, speciation as a
result of horizontal changes in information, or as a result of a
mutational defect with a loss of information) do not in themselves offer
evidence against 'big picture' evolution, since they can easily be
assigned a place within the overall model. However, one needs to
emphatically point out that they do not suffice to demonstrate the
validity of such evolutionary belief, since they can be just as easily
assigned a place within a creationist model.
Note also that some anti-creationists have mockingly
claimed that for a number of species to descend from one pair would
require that pair to have huge super-chromosomes to carry all the
information needed. While one cannot say dogmatically that existing
knowledge of genetic mechanisms is definitely sufficient to provide
for all the post-Flood variation needed (and in fact, some creationist
thinkers have postulated that there might have been as-yet-undiscovered
mechanisms as well), I suggest that the converse has not yet been
demonstrated. Maximum heterozygosity would surely give a massive variation
potential. Normal selectionist/adaptationist pressures, via Mendelian
reshuffling and sorting of that information could presumably see
substantial diversity arise within subsets of that information, just as
artificial selection has shown itself capable of generating many different
dog varieties, for example, in a few generations.
However, the reality is that, in the case of postulated
post-Flood variation in the creation model, the subgroups have the status
of separate species. That is, even though they may in some instances
interbreed in captivity, they generally do not do so in the wild. Thus
mechanisms of speciation, particularly rapid speciation, far from causing
creationists to shudder, are actually of great interest. In this light, it
was fascinating to read special reports on a major scientific conference
on speciation held in Asilomar, California in May. 1,2
Taking the most straightforward modern understanding of a
species (though not the only one, and not without its own problems), as a
group of organisms which can interbreed in nature and does not naturally
and freely interbreed with another, it is not hard to see how this sort of
variation (from selection of information subsets) could easily lead to
reproductive incompatibilities (as could mutational defects and
information losses, of course). It may be, for instance, that sheer size
differences would allow a population of Chihuahuas and Great Danes to be
classified as separate species, if found in the wild.
Since the cutting off of populations via physical
barriers (for example, mountain ranges) can easily be seen to isolate
subsets of genes, with the so-called founder effect, subsequent loss of
some genes through drift, etc., understanding how such physical barriers
could give rise to rapid speciation has always been fairly straightforward
(allopatric speciation). Nevertheless, the amount of post-Flood speciation
must have been staggering, particularly among the insects, and it is hard
to see how there could have been that many physical barriers, cut-off
founder or relict populations and the like in this time. Therefore, it is
both encouraging and fascinating for creationist biology to note that
there is now an increasing acceptance that sympatric speciation is
actually quite common. That means that a population may split into two
species even while living in the same area, with no separation or physical
barriers.
At the conference in question, evidence was presented of
this sort of thing having happened with ease in populations of certain
types of fruit-eating insects which used the fruits of their host plant
for courtship displays and mating. If one group of insects, used to eating
a certain type of fruit, starts to try a new host plant, then food choice
becomes linked with mate choice, and so reproductive isolation can begin.
It is interesting that no-one put forward any evidence that any new genes
arose by mutation — no new information seems to be required for any of
these mechanisms. Fish living in the same lake can also, it seems, become
reproductively isolated by way of genetically determined variation in food
choices, which leads to different sizes, and thus to differing mate
choices.
In another instance, several species of wasps appear to
have been thrust apart from a single ancestral wasp population by way of
nothing more than differing species of bacteria in their gut. Somehow, the
bacteria in the females destroy the DNA from males of the other species.
Other mechanisms of speciation mentioned were as simple as variations in
the song of a bird, or in a single pigment gene.
Hybridisation — the mixing of genes from two distinct
species — has been observed to form a third, reproductively distinct
grouping. Creationists would hold that the two species which hybridised
were likely to have previously formed from a single ancestral population
by way of non-evolutionary (that is, non-information-gaining) speciation.
(The hybrid species is not necessarily an exact reversion to the ancestral
form, of course, since this may have given rise to several other species
since the original creation.) Once again, no information appears de
novo which was not already in the biosphere; all that has happened is
that two sets of existing information have commingled. This clearly has no
apologetic value for macroevolution, therefore, but is yet one more
mechanism by which the creationist can account for the enormous increase
in post-Flood variation.
REFERENCES
-
Gibbons, A.,
1996. On the many origins of species. Science,
273:1496–1499. Return to text.
-
Morell, V., 1996. Starting species with
third parties and sex wars. Science, 273:1499–1502.
Return to text.
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