August 27, 2015 | David F. Coppedge

More Flaws in Darwin's Mechanism

Mutation and selection: we’re taught those pillars of neo-Darwinism from high school. How does it measure up to reality, though?

Before continuing, readers should understand that the debate about Darwinism is about major evolutionary change. Even the staunchest creationists allow for variability, sometimes called “microevolution,” that merely shuffles existing genetic information around. It’s the origin of new structures, organs and functions that neo-Darwinism is challenged to explain. When scientists go out to look for it, what do they find?

Mountaintop Speciation?

Borneo’s tallest mountain, Mt. Kinabalu, is the highest point between the Himalayas and New Guinea. A big team publishing in Nature cataloged most of the plants and animals on the summit to see what might have evolved in that unique, isolated environment. In a companion article in Nature, Alexandre Antonelli summarizes what they found:

  • Ever since the first botanical documentation of a tropical mountain by Alexander von Humboldt more than two centuries ago, naturalists have been fascinated by the diverse and unusual variety of life forms found on mountains. But we still lack answers to fundamental questions about the evolution of mountain biodiversity.
  • The location of Mount Kinabalu, surrounded by an exceedingly diverse tropical forest at the crossroads of Asia and Oceania, two regions that have their own distinct fauna and flora, apparently provided the mountain with a rich initial stock for the evolution of its unique biodiversity.
  • The first striking result is that most of the montane organisms examined are relatively young. They started to speciate during the past 6 million years, after, or at the same time as, the rise of the mountain they inhabit. Unlike the ancient creatures found on a remote tropical mountain in Arthur Conan Doyle’s novel The Lost World, this finding suggests a recent origin for montane species across the domains of life, and supports the recent speciation documented for alpine plants on several continents.
  • The second major finding is the dual origin of montane organisms (Fig. 1). Some of the species, in particular those found at the highest elevations of Mount Kinabalu, have their closest relatives outside of Borneo. Their ancestors were often good at dispersing, such as plants or fungi that produced large quantities of light seeds or spores that could be transported with the wind. Other species — about twice as many — derive from local ancestors at lower altitudes on the same island.
  • Finally, the authors’ analysis shows an overarching role for niche conservatism — the tendency for organisms to maintain their environmental preferences over evolutionary time. This result is evident both from the immigrant and the local lineages that gave rise to Mount Kinabalu’s biodiversity. Most of the ancestral species were already adapted to cool conditions, either in temperate regions or in other montane habitats. Even the lineages that ‘climbed up’ Mount Kinabalu often remained in the same broadly defined vegetation zone.

The research paper says, “many of these neo-endemics have not evolved by drastic niche shifts from local ancestors, but rather by immigration of pre-adapted propagules from elsewhere.” Needless to say, this doesn’t look like The Origin of Species. It looks like existing organisms found their way to the mountain habitat by dispersal or migration relatively recently, then stayed in their ecological niche. Some variation is evident, but not the formation of new species by macroevolution. What should be disturbing to any reader is that “The evolutionary origins of these unique biotas, however, are poorly understood“—after over two centuries since Humboldt’s epic voyages! How long will it take evolutionists to figure this stuff out?

Forces Against Natural Selection

Another paper, this one in PNAS, seems discouraging to believers in evolutionary theory. A team of Harvard biologists found that numerous forces act to counteract variation and selection. What’s “the fate of a mutation in a fluctuating environment“? It’s not good, if evolutionists want to hope that a rare beneficial mutation will get established and lead to a new structure or function. The reason is that the environment fluctuates. A beneficial mutation in one environment may become deleterious when the environment changes:

Evolution in variable environments depends crucially on the fates of new mutations in the face of fluctuating selection pressures. In constant environments, the relationship between the selective effect of a mutation and the probability that it will eventually fix or go extinct is well understood. However, our understanding of fixation probabilities in fluctuating environmental conditions is limited. Here, we show that temporal fluctuations in environmental conditions can have dramatic effects on the fate of each new mutation, reducing the efficiency of natural selection and increasing the fixation probability of all mutations, including those that are strongly deleterious on average. This makes it difficult for a population to maintain specialist adaptations, even if their benefits outweigh their costs.

They claim that selection is “well understood” for “constant environments.” How many environments, though, are constant? The world is always changing, especially when geologic ages are assumed. Continents get subducted, volcanoes erupt, climate changes, and major extinctions occur. At large scales, therefore, every environment fluctuates. If any rare, beneficial mutations try to get fixed, so as to “maintain specialist adaptations,” they are like blind swimmers trying to reach a target in cross currents and rip tides. More likely, harmful or neutral mutations will get fixed, reducing fitness.

We find that even in enormous populations, natural selection is often very inefficient at distinguishing between mutations that are beneficial and deleterious on average. In addition, substitution rates of all mutations are dramatically increased by variable selection pressures. This can lead to counterintuitive results. For instance, mutations that result in a trade-off but are predominantly deleterious during their lifetime can be much more likely to fix than mutations that are always neutral or even beneficial.

Readers should note that neutral drift is the enemy of natural selection. As their paper indicates, selection is blind to goodness and badness of mutations; what gets fixed in the genome is just what happens in a dynamic environment (see Stuff Happens Law). Another enemy is pleiotropy: the tendency of a beneficial mutation to have harmful effects elsewhere in the genome. It was hard enough for natural selection to achieve macroevolutionary progress without these “counterintuitive results.”

This theoretical paper, math and all, offers little hope for classical mutation-selection theory. Do the authors provide any example of an actual, observable mutation that produced a clear increase in fitness in any organism? No.

Vertebrate Origins

Nature published a special section on the origin of vertebrates. Most striking is this quote in the lead article by veteran evolutionary biologist Henry Gee, former senior editor of Nature:

BM-buddhaclickTo celebrate the golden jubilee of On the Origin of Species, in 1909, the Linnean Society of London held a special meeting on a hot biological topic of the day — the origin of the vertebrates. Such was the lack of consensus that one commentator, the zoologist T. R. R. Stebbing, wrote that “the disputants agreed on one single point, namely, that their opponents were all in the wrong.

The papers investigate “Scenarios for the making of vertebrates” with varying degrees of pomposity and discouragement. “Although our understanding is far from complete, it is much better than it was even 20 years ago,” Henry Gee intones hopefully. But looking over the papers shows a great deal of debate still in progress. The “scenarios” paper alone discusses four debates, one issue being “debated vigorously.” Janvier discusses three debates, remarking in one instance, “All these interpretations are either dismissed or still debated.” When all is said and done, it seems that Stebbing’s ironic assessment of consensus still fits.

A Success?

PhysOrg published an upbeat article about work at the University of Miami that seems to show evolution as a “tinkerer” instead of an “inventor.” The “inventor” option—possibly implying intelligent design—is less palatable to secular evolutionists than the “tinkerer” option, wherein evolution blindly cobbles together whatever solutions get by for the immediate present. The headline asks: “Is nature mostly a tinkerer or an inventor?

BM-wandclick“Our study paints a picture of nature innovating largely through sharing the functional bits of genestinkering with molecular genetic material that already exists,” said William E. Browne, assistant professor of Biology at UM’s College of Arts & Sciences and principal investigator of the study.

Investigating certain transcription factors that are “conserved during evolution” from microbes to man, the researchers decided that, over time, evolution is a tinkerer. It has swapped and rearranged protein domains, like words in sentences, to generate new functions (meanings) in various organisms. But they never mention mutation or selection. All they show is that, for each of the 48 species investigated, the genes function nicely. And what about the molecular genetic material the personified tinkerer works with? It “already exists,” they said.

Silliness

Despite all these failings with neo-Darwinism, evolution gets credited for everything in nature. Sometimes the examples get downright silly. Here’s one from Live Science: “Why do breakups hurt more for women? Blame evolution.

BM-DarwinBaloney-smSo, why are women more affected by breakups than men are? Well, from a scientific standpoint, women typically have more at stake in relationships than men do, said Craig Morris, a research associate at Binghamton University and lead author of the study.

Put simply, women are evolved to invest far more in a relationship than a man [is],” Morris said in a statement. “A brief romantic encounter could lead to nine months of pregnancy followed by many years of lactation for an ancestral woman, while the man may have ‘left the scene’ literally minutes after the encounter, with no further biological investment.

Many men would undoubtedly dispute this characterization—especially those unfortunate divorcees burdened with alimony and child support when the woman left against his heartfelt pleadings, or those men trying to preserve embryos he helped conceive, or those trying to stop the wife from aborting his child. Even so, is this situation the product of mutation and selection? Then there is no one to blame at all; certainly not a personified entity like “evolution.”

The inanity of simplistic evolution stories is only exceeded by the vacuity of the findings reported by its most sincere defenders. How long must society endure the uncritical propagation of this hopeless excuse for a “scientific” theory? Join the revolution against evolution. Don’t blame evolution; take responsibility! Blame evolutionists.

 

 

(Visited 90 times, 1 visits today)

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.