Darwinian Fitness/Selection Studies Lack Real-World Experimental Verification, Produce Contradictory
“Evolution: Do Bad Husbands Make Good Fathers?” is the provocative title of an article in Current Biology1 that conceals the real subject. The first paragraph of the article by David J. Hosken and Tom Tregenza explains the title:
Males sometimes harm their mates as they seek to maximise the number of offspring they sire. But are females really suffering or do the benefits of having sons that inherit their father’s manipulative traits make up for the costs? Three recent studies provide the first hard data addressing this issue, but they differ in their conclusions. (Emphasis added in all quotes.)
The article is deeper than a discussion of bad dudes; it is an analysis of the idea of sexual selection – what to Darwin was the second most effective agent of evolutionary change after natural selection. (The harmful males under investigation, by the way, are fruit flies, so not to worry, ladies.) Their critique of sexual selection experiments, however, applies equally well to natural selection experiments.
Hosken and Tregenza are not even sure that “harmful males” could drive the evolutionary process. They listed three reasons why the direct costs probably outweigh any indirect benefits.2 (Evolutionary benefits, after all, must persist in the grandchildren.) The question most interesting in this article is: has sexual selection theory ever been convincingly demonstrated in the wild? “Theory is all very well,” they say, “but as critics have repeatedly pointed out what we really need are good data.” The question implies a deficit in that regard – even when including the three recent studies that provided the “first hard data.”
That remark in the article begins a series of doubts over whether experimenters really know anything about selection – natural or sexual. Worse, the authors throw doubt on the validity of measuring fitness, arguably the most important parameter in all of Darwinian theory. In mentioning three studies (the ones that ”differ in their conclusions”) they note in passing that one of them “sidesteps many of the problems associated with measuring fitness.” None of the three studies seems to succeed. The first tries to see if the harm caused by the males is compensated in other ways; the second tries to measure “total fitness” in a laboratory setting. These two studies produced opposite findings. So what are we to conclude, they ask? Watch out: “Perhaps, the main lesson is just how difficult it is to measure something as slippery as fitness.”
They turned to the third study, which supposedly sidestepped many of the problems. It found a possibility that the fitness cost of harmful males might be compensated for by indirect benefits. But this study had other problems. It was conducted in a very artificial laboratory environment – not out in the real world. They question whether scientists have ever rigorously determined how sexual selection might operate where it counts – in nature:
The population was established over 300 generations ago and has been maintained continuously at high population size to retain genetic diversity. The authors claim that this approach means that the flies have had time to become adapted to the laboratory. Although this may be true in the sense that alleles present at low frequencies in the wild population that are beneficial in the lab can be expected to have raced to fixation, it cannot be true in the broader sense of gradual evolution through new mutations. A small glass tube in which males and females are forced into close proximity and walk around on a sea of food bears little resemblance to the varied natural environments where D. melanogaster are found, and it is safe to assume that there will be a continual stream of new mutations that prove beneficial on this laboratory island. Indeed, recent work documents on-going evolution in fly populations maintained in the lab for over a 1000 generations. This constant adaptation to the lab may mean that naturally selected differences between individuals are much more important than sexually selected differences, but whether this is the case in the wild is a point of contention. A second issue is that the lab is particularly unusual in relation to conflicts over mating because of the high-density housing conditions and females cannot escape from males since they are robbed of their major natural defence, which is to simply fly away….
One begins to wonder if all this talk about mean-old males, for instance, is an artifact of the lab setup. After all, how would humans get along after being packed shoulder-to-shoulder in prison for 1,000 generations? That question aside, Hosken and Tregenza now hit home and hard. Sexual selection theories need more scientific rigor, and their ending paragraph indicates that convincing experiments have never yet been done.
But we still have no clear idea what the relative magnitude of direct and indirect effects are generally.2 If we are really going to move this debate forward and out of the lab, incorporating the full gamut of costs and benefits of sexual selection, then systems are needed where trans-generational fitness can be measured in nature. Tellingly, in one of the few long-term studies of organisms in the wild, sexual selection is reported to have no fitness consequences, which suggests either the equilibrium situation Fisher envisaged (where the benefits of choice are balanced by natural selection costs), or perhaps that the costs and benefits of sexual selection alone are balanced. If this is the case, and costs generated through sexual conflict are balanced by benefits through traditional sexual selection mechanisms, then we may not expect sexual selection to drive rapid evolutionary change. Determining how commonly males impose serious costs on females without compensatory benefits in nature is the next major challenge in the study of sexual conflict.
One interesting footnote. Want to know what they were referring to in “one of the few long-term studies of organisms in the wild”? Check the references: it was Peter and Mary Grant’s 2002 study of the Galapagos finch populations, entitled, “Unpredictable evolution in a 30-year study of Darwin’s finches.”
1David J. Hosken and Tom Tregenza, “Evolution: Do Bad Husbands Make Good Fathers?” Current Biology, Volume 15, Issue 20, 25 October 2005, Pages R836-R838.
2For information on the impact of “indirect genetic effects” on natural selection (i.e., “slippage on the treadmill”), see these entries: 03/17/2003, 07/23/2003, 10/19/2004.
It is said that those who respect the law and love sausage should never watch either being made. The same could be said of Darwinian theory. It’s packaged in the textbooks nice and neat, but inside it is full of baloney, fat, and filler, the composition of which you would not want to know.
Let the reader understand. These two knowledgeable scientists, both evolutionists at the Centre for Ecology and Conservation in Cornwall, UK, have just spilled the beans. They confessed in print that there is no real-world, long-term, multi-generational study of any animal that proves sexual selection accomplishes anything! They effectively pulled the rug out from the lab studies by emphasizing how artificial they are. But what Darwinist has ever taken the time to watch critters in their natural habitats, without interference, and actually get a grip on the slippery parameter called “fitness” so as to prove Charlie right? Peter and Mary Grant? Ha! All they showed after 30 years was that evolution is unpredictable, and oscillates back and forth (08/24/2005). Their results, after probably the longest and most detailed experiment in the history of evolutionary research, showed no net evolution – and even they complained that 30 years is probably way too short (considering how slowly evolution must act) to draw any firm conclusions (04/26/2002). As far as anyone could know, the finches were essentially unchanged since Darwin’s visit in 1832. Where is the evolution? Yet their study is often cited (10/24/2004 commentary), as it was here, as one of the few long-term, real-world examples of evolution at work.
Notice that whatever undercuts the value of sexual selection, the silver coin in Darwin’s currency, also undermines the golden coin: natural selection – because both depend on the concept of “fitness.” Fitness is just as slippery a metric in either case (see the 10/29/2002 entry, “Fitness for dummies: Is it running in circles?”).
To be considered scientific, a theory needs mathematical and observational rigor. Mere hand-waving with charts and graphs and lab activity won’t cut it. Also, for a theory to gain credibility, experiments should reinforce one another, not lead to opposite conclusions. Hosken and Tregenza’s article ended like most Darwinian papers, with appeals to the future: “We need more data” or “We need more fossils” or “We need more real-world experiments.” When Darwinists cannot even define their parameters or measure them, let alone study them in realistic settings, one begins to get the distinct feeling that this has been a 146-year long con game.
Admissions like this should make one angry. Dr. Richard Weikart, in his recent book From Darwin to Hitler (Palgrave Macmillan, 2004), quoted page after page after page of influential German thinkers after Darwin – scientists, doctors, eugenicists, militarists, ethicists, philosophers and political scientists – who built their entire worldview on this slippery notion of Darwinian “fitness” (for instance, see the quote at the top right of this page). The fit overpower the unfit. This is the law of nature: Darwin proved it. The strong overcomes the weak. The superior race exterminates the inferior race. The healthy deserve to live; the weak should get out of the way or be sterilized lest they contaminate society. Whole groups of innocent people were deprived of basic human rights when categorized as “unfit”: first criminals, mentally ill, “idiots” and “imbeciles” and other “defectives”, then handicapped, elderly, sickly, deformed, “primitives,” and finally entire races, countries and continents. We all know what happened next. And now they tell us they can’t even measure fitness, which means they don’t even know what it is. Yet today the same Darwinian worldview reigns nearly unchallenged in academia and the centers of intellectual power, built on the very same slippery concept of “fitness.”
As we weep over the mass graves of the victims of this false and destructive doctrine, let us rush to Dover and demand accountability, as we vow, with informed passion: Never again.