There are things we know about evolution that Darwin never imagined, and we've made many discoveries that weren't part of the "modern synthetic theory of evolution". The neutral theory and epigenetics were not imagined by Darwin, but the EES sometimes try to pretend that it is. That is what the article states. There is an answer to the question.
We don't need a new theory of evolution because the basic theory proposed by Darwin in 1859 still holds. Most of it can be incorporated into evolutionary biology because we know so much more now. If you look at evolution textbooks from a few years ago, you will find phenomena like epigenesis, the neutral theory, and the like, not only discussed, but also shown to have been part of discussions about evolution for a long time. They are part of evolutionary biology, which has expanded, but not in a way that requires replacing the old theory. We add new stuff to the field as it turns up, and then discard the stuff that turns out to be incorrect.
Stephen Buranyi, a Guardian science writer, can't help but distort the history of evolutionary biology and argue that evolutionary biology needs a rehaul. Buranyi thinks that the scientific debate about the importance of different factors in evolution is a culture war. It is a normal debate in science and the outcome depends on facts.
You can click to read it.
I will only take five of Buranyi's claims because there is too much to criticize and correct here.
It's a word It's true that we don't know the exact sequence in which some complex adaptation developed, and we won't because we weren't there We have the fossils to show you how whales evolved from hoofed ungulates. It's the same for evolutionary transitions like from fish to salamanders. Buranyi resurrects the old criticism that "how could an eye possibly evolve in a stepwise fashion from a simple light-sensitive spot?" The implication is that we don't know how this happened and that it's wrong with evolutionary theory.
The problem was first considered by Darwin and discussed more extensively by Richard Dawkins. We don't know how eyes evolved, but we have a plausible sequence about how one can go, from a light-sensitive eyespot to the complex "camera eye" of mammals. Estimates of parameters allow us to show that there was plenty of time for this to occur. The evolution of the eye is not a problem for simple Darwinism if we can do that.
A paper published in 1994 by Nilsson and Pelger showed that you could model the evolution of a camera eye from a light-sensitive spot. Dawkins wrote an article about the eye in a twinkling.
Buranyi cites the eye as an insuperable evolutionary problem.
You may recall the gist from school biology lessons. If a creature with poor eyesight happens to produce offspring with slightly better eyesight, thanks to random mutations, then that tiny bit more vision gives them more chance of survival. The longer they survive, the more chance they have to reproduce and pass on the genes that equipped them with slightly better eyesight. Some of their offspring might, in turn, have better eyesight than their parents, making it likelier that they, too, will reproduce. And so on. Generation by generation, over unfathomably long periods of time, tiny advantages add up. Eventually, after a few hundred million years, you have creatures who can see as well as humans, or cats, or owls.
This is the basic story of evolution, as recounted in countless textbooks and pop-science bestsellers. The problem, according to a growing number of scientists, is that it is absurdly crude and misleading.
For one thing, it starts midway through the story, taking for granted the existence of light-sensitive cells, lenses and irises, without explaining where they came from in the first place. Nor does it adequately explain how such delicate and easily disrupted components meshed together to form a single organ. And it isn’t just eyes that the traditional theory struggles with. “The first eye, the first wing, the first placenta. How they emerge. Explaining these is the foundational motivation of evolutionary biology,” says Armin Moczek, a biologist at Indiana University. “And yet, we still do not have a good answer. This classic idea of gradual change, one happy accident at a time, has so far fallen flat.”
Both of them are incorrect. The process of meshing the various components has been modeled and we can see that it is an adaptation in one. We don't know when and where things occurred. We can model the process without difficulties because we see a plausible order. The idea of gradual change has fallen flat. Buranyi thinks the eye appeared to be a singlemutation. There is more to come on that issue. His distortions of history begin at the beginning of the article.
A. Evolutionary biology neglected plasticity. The ability of an organisms genome to respond to different environments in different ways is called plasticity. When there is too much sun, we get tans. In the winter, mammals grow long hair and lose it in the summer. Plants can change their form depending on where they are growing, and fish-deterring ruffs can grow in water if they develop in it.
The evolution of plasticity is something we have known for a long time. A genome that responds to different environments is easy to imagine. A fantastic example is how the same genome can be used to produce a butterfly in different environments. There is a good chance that you will find yourself in environments A, B, C, or so on. The chance that the environment will be white in winter and brown in summer is 100%, but the chance that we will get a tan is less than that. If enough people are out in the sun, it doesn't need to be 100%. The tanning response is included in our genome.
The idea of "genetic assimilation" was discussed and demonstrated eighty years ago.
Buranyi believes that plasticity is a non-Darwinian phenomenon. He gives some great examples of plasticity. His words were bold.
One of the most fascinating recent areas of research is known as plasticity, which has shown that some organisms have the potential to adapt more rapidly and more radically than was once thought. Descriptions of plasticity are startling, bringing to mind the kinds of wild transformations you might expect to find in comic books and science fiction movies.
. . . Plasticity doesn’t invalidate the idea of gradual change through selection of small changes, but it offers another evolutionary system with its own logic working in concert. To some researchers, it may even hold the answers to the vexed question of biological novelties: the first eye, the first wing. “Plasticity is perhaps what sparks the rudimentary form of a novel trait,” says Pfennig. [JAC: Pfennig is just guessing here.]
Plasticity is well accepted in developmental biology, and the pioneering theorist Mary Jane West-Eberhard began making the case that it was a core evolutionary force in the early 00s. And yet, to biologists in many other fields, it is virtually unknown. Undergraduates beginning their education are unlikely to hear anything about it, and it has still to make much mark in popular science writing.
The new "logic" is involved in the process of plasticity. The evolution of plasticity follows the logic of natural selection when there are environmental conditions that can change. It pays for your genome to adapt to different environments.
The evolution textbooks make it clear that students aren't exposed to this. I pulled Doug Futuyma's 1998 (third edition) textbook Evolutionary Biology off my shelf, and there's a whole section on "norms of reaction", as they used to. A norm of reaction is when a given genome can respond to different environments and produce different types of cells. The phenomenon was discussed for a long time before the publication of Doug's book.
It's a combination of c. and d. The idea of a complex feature coming into being in a single step has been neglected by biologists. Goldschmidt believed thatmutationism was an alternative to natural selection. That means a huge step rather than a gradualistic evolution of reptile into bird.
There were a number of reasons why macromutationism lost plausibility. There is a very low chance that a coordinated and cooperative set of features could arise in one step. These are developmental anomalies that are maladaptive and can be seen in the lab, like an eye developing on a wing. The shape of insect genitalia, for example, has been shown to be the result of several small changes in genetics. There is no evidence for the importance of large effect in evolution.
Even if a macromutation happened, it wouldn't spread through a species without natural selection. mutationsm isn't an alternative to selection.
The data has finally been obtained. Major changes like the evolution of birds, whales, amphibians, hominins and the like are documented in the fossil record, but there are no macromutations. I can't point to a single adaptation in nature that requires us to postulate macromutations because the feature can't be produced by a stepwise accumulation of smaller Mutations do vary in size but I can't point to a single adaptation in nature that requires us to postulate macro IDers like Behe use God instead of macromutations to bridge the gap.
Buranyi suggests that macromutation is neglected.
Even more ominous for Darwinists was the emergence of the “mutationists” in the 1910s, a school of geneticists whose star exponent, Thomas Hunt Morgan, showed that by breeding millions of fruit flies – and sometimes spiking their food with the radioactive element radium – he could produce mutated traits, such as new eye colours or additional limbs. These were not the tiny random variations on which Darwin’s theory was built, but sudden, dramatic changes. And these mutations, it turned out, were heritable. The mutationists believed that they had identified life’s true creative force. Sure, natural selection helped to remove unsuitable changes, but it was simply a humdrum editor for the flamboyant poetry of mutation. “Natura non facit saltum,” Darwin had once written: “Nature does not make jumps.” The mutationists begged to differ.
These disputes over evolution had the weight of a theological schism. At stake were the forces governing all creation. For Darwinists especially, their theory was all-or-nothing. If another force, apart from natural selection, could also explain the differences we see between living things, Darwin wrote in On the Origin of Species, his whole theory of life would “utterly break down”. If the mutationists were right, instead of a single force governing all biological change, scientists would have to dig deep into the logic of mutation. Did it work differently on legs and lungs? Did mutations in frogs work differently to mutations in owls or elephants?
. . . The modern synthesis was such a seismic event that even its flatly wrong ideas took up to half a century to correct. The mutationists were so thoroughly buried that even after decades of proof that mutation was, in fact, a key part of evolution, their ideas were still regarded with suspicion. As recently as 1990, one of the most influential university evolution textbooks could claim that “the role of new mutations is not of immediate significance” – something that very few scientists then, or now, actually believe. Wars of ideas are not won with ideas alone.
Everything gets messed up by this. The evidence againstmutationism is missing and it implies that "mutationists" just emphasized the importance of evolution. Variation of large effect are important in evolution, but drive evolution without the need for natural selection according to Variation of large effect are important in evolution, but drive evolution without the need for natural selection according toVariation of large effect are important in evolution, but drive evolution without the need for The gas and the car are both important for adaptive evolution. One is more important than the other. Buranyi has done the reader a disservice by giving a misleading account of the history of biology here.
It's a d. Punctuated equilibrium was only about the pace and timing of evolution.
Other assaults on evolutionary orthodoxy followed. The influential palaeontologists Stephen Jay Gould and Niles Eldredge argued that the fossil record showed evolution often happened in short, concentrated bursts; it didn’t have to be slow and gradual.
The real critique of evolutionary orthodoxy was the linking of a jerky pattern in the fossil record to a novel and almost non-Darwinian process. The process of species selection that operates in nature is not the same as the process Gould suggests.
Experiments and pieces of theoretical work showed the failure of Gould's theory, including adaptive valley crossing via drift. I don't know if the "jerky" fossil record that gave rise to the postulate processes is still accepted by paleontologists, but the reasons Gould and Eldredge advanced for such a pattern are incorrect. An incomplete fossil record or a process of natural selection are some of the reasons forjerky evolution.
E. The scientific debate about the ambit of evolution is a culture war.
To release biology from the legacy of the modern synthesis, explains Massimo Pigliucci, a former professor of evolution at Stony Brook University in New York, you need a range of tactics to spark a reckoning: “Persuasion, students taking up these ideas, funding, professorial positions.” You need hearts as well as minds. During a Q&A with Pigliucci at a conference in 2017, one audience member commented that the disagreement between EES proponents and more conservative biologists sometimes looked more like a culture war than a scientific disagreement. According to one attender, “Pigliucci basically said: ‘Sure, it’s a culture war, and we’re going to win it,’ and half the room burst out cheering.”
It was a bad call. It isn't a culture war even if scientists use terms like "evolution by jerks" to describe advocates of punctuated equilibrium That kind of acrimony was not included in the scientific argument used to conduct the debate. There is a debate about evolution's mechanisms. There is no reason to say neo-Darwinism is obsolete since the Modern Evolutionary Synthesis includes stuff that we didn't think of 80 years ago. Expansion is ok, but saying that we need a new theory of evolution is both ignorant and hyperbolic.
I can write about the errors and distortions of Buranyi's piece for a while, but I'm tired. There are a few examples of the misguided nature of his article. It makes people think that there is something seriously wrong with the theory of evolution. I think the IDers are already lapping up the Guardian piece.
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