Denyse is at it again. Doesn't her garden get a little crowded with straw-men? In her latest post she takes on sex, as in "Can Sex Explain Evolution?". That's pretty silly because by itself, the answer is no, but it's part of a much larger process that certainly does have a part in explaining evolution, and rather well.
She first redefines evolution again:
"The mere process of eliminating unfit examples of a type in a given environment builds up information over time, resulting in huge new layers of complexity."I would rather not go over it again, can we just say that I think Denyse skipped 6th grade science class and leave it at that.
Here is where I think Denyse loses it.
"But if no one can say what is fit or unfit according to natural selection, because nature has no direction, why must we pay attention to claims about natural selection? "She seems to assume there has to be something directing traffic, and assumes it must be goal-oriented for some reason because it has to decide fitness. She can't except the reality of Natural Selection, so she tries to use Sexual Selection to create her strawman of needing an intelligence. Then when she shows there is no intelligence, she dismisses it as impossible. The economist who described 'survival of the fittest' was not describing evolution, and even though biologists don't use that term, at least not without a lengthy explanation, Denyse can't seem to grasp that evolution does not equal survival of the fittest in it's barest form. Come on Denyse, you should be more familiar with your subject by now, shouldn't you?
But what does the selecting? As it has been explained over and over again, the environment an organism exists within. It's not that hard to understand, well that is if you actually want to understand. Another thing Denyse tends to forget is that the process of evolution can be summarized in three sentences: Genes mutate. Individuals are selected. Populations evolve.
We've discusses genes mutating several times. The simplest example is this, look at a child and look at that child's parents. Without doing a genetic analysis, you can easily see that a child is not a carbon copy of one parent, but an amalgamation of the two. But you will most likely see traits that don't exist in either parent. If you do the genetic analysis you can see the differences more clearly. This is an example of mutation. Unlike the comic version, mutations are rarely large scale changes like 4 hands, but most are small differences that have little impact on much of anything. There are many, many examples of genes mutating, Prof. Richard Lenski's long-term evolution experiment is another excellent example, and one well documented. Of course about now Creationists like to trot out the odds argument, but in humans there are an average of 150-200 mutations per offspring, when compared to the parents. That's not 150-200 mutations per generation, but per off-spring. So when you look at an entire generation of people, there are 150-200 mutations times the total number in that population, a staggering number. In the US in just one year an estimated 3.8 million babies are born. That's about 600 million mutations, in one year. Suddenly the odds argument makes even less sense than usual.
Here is where Denyse gets hung up, 'individuals are selected'. She seems to think that means literally selected! Someone has to line 'em up and point to the ones that survive and let the others just drop dead. Sorry, Denyse, doesn't work that way.
When talking about evolution, we aren't talking about an pointing finger selection, nothing like the life guard at the gene pool, "Hey, you outta the pool, you aren't allowed to procreate!" We are talking about genes that affect survival and reproductive opportunity. Genes that increase either, or both of these, will show a demonstrable increase within the population. Note -- within the population! Genes that negatively affect either of these will show a decrease. That's not to say an individual cannot or will not procreate, but that over time the allele frequency within a population will change based on the environment. In her own example there is nothing in evolutionary theory that says Tom, Dick, or Harry will or will not procreate. There isn't even anything determining their fitness. Her view of sexual selection is rather limited, isn't it?
She tries to use 'sexual selection' as a mechanism for major evolutionary changes, yet it is only one of the mechanisms for evolutionary change. Whether or not it's a major change depends on many factors that Denyse doesn't seem to mention. For example, I've talked before about Elephants and how for years, if not centuries, large tusked males had an evolutionary advantage and subsequently had more offspring. The alleles for large tusks increased with the population until it was at something like 90%. Then along came hunting and poaching. and now the alleles for large tusks are a disadvantage (a change in the environment). Suddenly when mating season starts, there are fewer and fewer tusked males, so the tusk-less males, are the only game in town. Now it's 90% tusk-less offspring. Can you better see the 'selection' now, Denyse? Yes, I bet if you ever read this, you'll claim since man is doing the selection for tusks, it's an intelligence. Although I would debate the use of the word intelligence for hunting a species to the point this happens, but the environment is still doing the selection, regardless of the reason for the decreasing population of tusked elephants.
My favorite example of sexual selection was a joke "Why do rock stars marry super models? Because they can!" Think about it and look at some of the rock stars. Ugly human beings, take Mick Jagger for example! If he weren't the front man of Rolling Stone, do you really think he would have had 7 children with 4 different women (multiple super models!) if he were not the front-man for the Rolling Stones? His oldest and youngest are 29 years apart! That's sexual selection! His genes have spread further in the human population than my much more modest efforts, but then I can't sing a note. Well that's not true. I can sing one note, it's when I try and piece two or more together that people start running from the room.
The reality is the concept of sexual selection has expanded a great deal since Darwin first postulated it. But of course Denyse can't seem to get the idea that Darwin is not the end-all of evolutionary theory, can she? It also looks like Denyse is using a common Discovery Institute tactic, demanding a complete and absolute answer or she dismisses anything less. We've talked about that before. They offer nothing and expect acceptance, but if a real scientists can't be 100% absolute, they are in the wrong. Science doesn't work that way, but is anyone surprised that Denyse may be lacking in basic science methodology?
Her last line:
"We are still stuck for a mechanism that replaces intelligence."Why? Since intelligence wasn't in the mix to begin with, we don't need to replace it. Denyse, you haven't made an argument that intelligence is required or even necessary. All you did was to toss out an argument that you find it impossible to accept that intelligence isn't a requirement and seeing if your argument sticks. Nope, it slid to the floor like under-cooked spaghetti. All in all, it looks like one large argument from incredulity, that is since Denyse believes intelligence is required, she demands there must be intelligence, regardless of a lack of evidence.