Dolphins and Cows Again

Now lets examine the implications of the model, and the data:

12 differences / 100 bases = The cow differs from its common ancestor with the dolphin in 12% of its DNA bases.

7 / 100 = The dolphin only differs from their common ancestor in 7% of DNA bases.


Since it is agreed that each species mutated in quite different directions,
and that backtracking is virtually impossible under normal conditions,
its a safe bet that:
virtually all DNA mutations in the Dolphin line that move it
away from the common ancestor also move it away from the cow.
Few if any of those mutations will 'reverse' DNA evolution or bring
the species closer together.  Even the sites of mutation will be different,
virtually guaranteeing that the mutations will all be unique, and non overlapping.

The measure of genetic 'distance' from the central (common ancestor) point,
can simply be added together, or even more plainly, placed on a horizontal
'distance' numberline:

Now however, the connection point to the rest of the phylogenetic tree
must be decided.  This is done on the basis of a crude, literal 'parsimony',
taking the DNA alterations at face value. 

 

As a scientific procedure however, this has extremely dubious value,
because there is no 'one-to-one' correspondence between a nucleotide change,
and a real feature or characteristic of an actual species or individual.

Many mutations have no effect at all, and no informational value,
and no relevance to Speciation in particular or Evolution in general.
Such mutations give 'Natural Selection' nothing to work with,
and the only measurable effect is a slow, relatively benign 'genetic drift'.

A REAL attempt at a meaningful and probable location-point for common
ancestry and speciation would take into account both the morphology and
the glaring differences in function between animals, which would
interact with the environment to actually drive Natural Selection in
a plausible and comprehensible fashion.

It is trivially obvious that a cow is far more similar to a horse, dog, cat, and alpaca, than it is to a dolphin, and the crude and literal measure of
'DNA differences' at a nucleotide level is both misleading and useless.

Environmental changes drive Natural Selection, and we can expect that
drastic environmental changes force rapid Natural Selection, i.e.,
punctuated equilibrium style effects, and such is the very example before us.

The following phylogenetic connection takes into account rationally
both what the theory of Evolution predicts, and what the data really
indicates.  If the mutations themselves are semi-random processes,
only constrained by survival and reproductive forces, then they will
likely target critical and non-critical segments of DNA in the same proportions
that these appear. 

Since it is Natural Selection itself which determines which DNA modifications
are adopted generationally, its obvious that there should be more DNA changes
where Natural Selection can be expected to be more intensive and active.

This tree places the 'common ancestor' at a point which will account for
the expected differences in mutation rates, caused by the different intensities
of Natural Selection operating in a background milieu of Genetic Drift.

It further poses the likelihood that the common ancestor of the cow and dolphin
was a land animal, unremarkable, and much closer to its other near relatives,
such as horse, alpaca, dog and cat, than to sea creatures.

The difference between the two reconstructions is simply that
the genetic data is not blindly applied in a clumsy and mindless fashion,
but is interpreted by the Theory of Evolution itself, and integrated into
an intelligent picture of the speciation process.

Although this is not any kind of evidence in favour of the Theory of Evolution,
it is necessary to impose upon any interpretation of data (genetic or otherwise),
the constraints which the Theory itself poses.