Pahu said:
Not having read the book, it is a bit difficult to comment.
(...)
"No known mechanism will cause macroevolution" ?
Of course, known mechanisms will. I know that it is your job as a creationist to reject these, but mutation and natural selection are known mechanisms...
Furthermore, the use of the term "macroevolution" suggests he accepts micro evolution, does dear Mr. Brown offers a reason why many microevolutionary would not add up over time into macro-evolution?
Yes he does here:
http://www.creationscience.com/onlinebook/LifeSciences2.html#wp2752687
Here is the actual text linked:
Increased complexity would be shown if the offspring of one form of life had a different and improved set of vital organs. This is sometimes called the molecules-to-man theory—or macroevolution. [See Figure 4 on page 6.] Microevolution, on the other hand, does not involve increasing complexity. It involves changes only in size, shape, or color, or minor genetic alterations caused by a few mutations. Macroevolution requires thousands of “just right” mutations. Microevolution can be thought of as “horizontal” (or even downward) change, whereas macroevolution, if it were ever observed, would involve an “upward,” beneficial change in complexity. Notice that microevolution plus time will not produce macroevolution. (micro + time ≠ macro)
Creationists and evolutionists agree that microevolution (and natural selection) occur. Minor change has been observed since history began. But notice how often evolutionists give evidence for microevolution to support macroevolution. It is macroevolution—which requires new abilities and increasing complexity, resulting from new genetic information—that is at the center of the creation-evolution controversy. Therefore, in this book, the term “organic evolution” will mean macroevolution.
I am not impressed.
"Increased complexity would be shown if the offspring of one form of life had a different and improved set of vital organs."
First of all, pet peeve of mine, improved? Evolution is not directional, from protists, or molecules, to man. That's a very XIXth century misconception.
Second; one offspring? WTF... Evolution takes place over many generations, not over one!
Third; is everything short of the apparition of new organs considered micro-evolution now? The apparition of new organs is actually a very rare evolutionary event. For example, most of our organs can be found outlined in fish... I have often sometime seen microevolution as defined (when creationist get themselves tricked in giving a firm definition) as evolution within a species... Here, Brown's definition could theoretically be employed at the phylum's level...
"Macroevolution requires thousands of “just right” mutations."
Yes... and no.
If you accept microevolution like Brown does, this microevolutive mutations will give some small amounts of evolutionary advantage to the species, and hence be selected for. When the next tiny evolutionary step, another microevolutionary event arrive, it will occur in a population that has already been selected for the first one, and so on...
So, yes, macroevolution is a thousand of "just right" mutations, but because selective pressure occurs continually at each step of the way, it ensures that all these mutations will be "just right" by slowly weeding out the wrong ones...
Basically, Natural selection will give a general trend (upward, downward, sideways...) to these micro-mutations...
"Notice that microevolution plus time will not produce macroevolution. (micro + time ≠ macro)"
But, it would...
As we have said, micro-evolution occurs, somewhat regularly. So, if you give more time, you give more time for micro-evolutionary events to occur, with time for natural selection to make the most beneficial versions of whatever gene the prevalent ones...
By definition, micro-evolution+time gives a bunch of micro-evolution selected toward an optimum fitness = macro-evolution...
"macroevolution, if it were ever observed, would involve an “upward,” beneficial change in complexity."
No it would not necessarily, remember, it's not the XIXth century anymore and evolution is not following a straight path toward or glorious naked-apeness.
"But notice how often evolutionists give evidence for microevolution to support macroevolution"
Because evolution is evolution, the distinction micro-macro evolution is pretty much arbitrary... and mostly used by goalposts shifting creationists...
The continual pilling up of thousands upon thousands of what Brown calls 'micro-evolution' will inevitably lead to macroevolution...
So, yeah, obviously, "micro-evolution" is faster and easier to observe and we have many more examples of it to give... But it's not like we don't have
examples that'd fit what most creationists would define as macro-evolution (until they redefine the term as needed).
It is macroevolution—which requires new abilities and increasing complexity, resulting from new genetic information
You know, literally any alteration to a gene will produce a new gene sequence that was not here before, so, by definition "new genetic information". That is a VERY VERY silly thing to say Mr. Brown...
As I said, I am not impressed.
As I expected, Brown fails to clearly explains why multiple micro-evolution changes selected by natural selection would not produce macro-evolution.
There is some hints, the use of the term 'offspring' (singular) and the concept of 'thousand of "just-right" mutations', to me suggest that Brown is not actually understanding the concept he is arguing against. It suggest, to me, that he is attacking some sort of Goldschmidtian's hopeful monster, a concept long rejected, so, actually, a strawman of the evolutionary theory...
