You don’t get to revise evolutionary theory, until you understand evolutionary theory [Pharyngula]


There was a conference sponsored by the Royal Society last month, titled New trends in evolutionary biology: biological, philosophical and social science perspectives. There have been a number of news stories about this event, some good, some bad. Here’s one: can you tell what’s wrong with it?

For example, speaking at the Royal Society was Melinda Zeder, who talked about the way in which modern synthesis fails to provide a reason for mankind’s turning to agriculture 10,00 years ago and its ensuing evolutionary impact. Growing crops may have taken years, so there could not have been a short-term evolutionary benefit to it. As Zeder told Quanta, “You don’t get the immediate gratification of grabbing some food and putting it in your mouth.” It’s also been theorized that a climate shift caused agriculture to bloom, but there’s no evidence of such a shift.

If you’re not seeing it yet, focus on this statement: Growing crops may have taken years, so there could not have been a short-term evolutionary benefit to it.

Think about it. Imagine…when I was born, I did not immediately inseminate a nearby female, instead waiting 24 years, and even if I had been capable, it would have taken her almost a year to produce offspring for me. Because it lacks immediate gratification, there can not be any short term evolutionary benefit to reproduction.

That’s embarrassingly idiotic. Evolution is something that happens to populations, not individuals, and short-term evolutionary advantages are those that produce a benefit for the next generation. A nomadic tribe sowing seeds at their camp in the spring before following the herds for the summer, so that when they return in the fall they find a crop of edibles that provide a consistent food source sounds exactly like the kind of short-term investment that would produce an evolutionary advantage.

But this whole article sounds this way, like it was written by a clueless reporter discussing a meeting of ambitious ignoramuses who don’t understand what they’re criticizing. Look at the title: How About a New Theory of Evolution with Less Natural Selection? Say what? You do know that evolutionary theory already includes multiple modes of evolutionary change beyond selection, and it has had them quantified and described since the 1930s, right? Every competent evolutionary biologist since the 1970s has embraced the mathematics of Kimura and Ohta and knows that evolution is not solely driven by selection, and at the same time, they have not shouted “Revolution!” at the inclusion of new, better, mathematical descriptions of the evolutionary process.

Likewise, many of the revolutionaries at this meeting talked about epigenetics as if it were some shocking new thing that could not possibly be accommodated in a neo-Darwinian framework. I just want to reply “Waddington, in the 1940s”, but I feel like it would be received in this crowd like saying “Darmok and Jalad at Tanagra”. They just don’t have the referents to understand it.

This reporter even mentions one of my primary objections to the invalid over-emphasis on epigenetics in evolution.

Scientists used to believe that when a offspring is born, it starts with a clean epigenomic slate. This turns out not to always be the case, at least in plants and fungi, and maybe in invertebrates. Some epigenetic tags survive, and thus “epigenetic inheritance” may play a role in the organism’s evolution.

First “used to believe”? When? This is simply sloppy history. Waddington’s epigenetic influences were largely abstract and hypothetical; they wouldn’t become more concrete until details about such phenomena as DNA and gene regulation and methylation were discovered. It’s clear that there are ongoing epigenetic changes during development, so obviously there can’t be an epigenetic state for the organism. The gamete is a specialized cell type, so it has to have its own special epigenetic marks; we see this in imprinting. Of course the epigenetic state of the oocyte is largely reset not to a “clean” state, whatever that means, but to a totipotent state, which is something altogether different. That some gene states that have physiological or morphological effects in the adult persist for multiple generations is neither surprising nor requiring major renovations of evolutionary theory.

I also have to point out that Jacob and Monod’s Lac operon work showed that E. coli passes on an epigenetic state after cell division. This is not a wild and crazy revelation that necessitates radical changes in the theory.

They also talk a lot about plasticity. Plasticity is important, no denying that, but plasticity has also not been ignored: I just want to chant another phrase, “Clausen, Keck, Hiesey, 1930s.” This is not a neglected topic.

I found this article infuriating because here we have a group of people declaring that we need to greatly modify the neo-Darwinian Synthesis but they constantly demonstrate that they don’t understand it. You can’t propose changes to an idea if you haven’t done your homework and shown some detailed knowledge of what you think needs revision. They haven’t done their background research.

Another problem I have with this kind of meeting is that they’re always infested with crackpots. This one had Denis Noble, and disgraceful dingleberry who believes that mutations are non-random and that acquired characteristics can be inherited and that evolutionary change is entirely saltational. He’s nuts. At least Carl Zimmer captured some of the pushback against Noble. I’ve got to admit it’s kind of hilarious to read about David Shuker shooting down Noble’s distortion of a paper.

“This strategy is to produce rapid evolutionary genome change in response to the unfavorable environment,” Noble declared to the audience. “It’s a self-maintaining system that enables a particular characteristic to occur independent of the DNA.”

That didn’t sound right to Shuker, and he was determined to challenge Noble after the applause died down.

“Could you comment at all on the mechanism underlying that discovery?” Shuker asked.

Noble stammered in reply. “The mechanism in general terms, I can, yes…” he said, and then started talking about networks and regulation and a desperate search for a solution to a crisis. “You’d have to go back to the original paper,” he then said.

While Noble was struggling to respond, Shuker went back to the paper on an iPad. And now he read the abstract in a booming voice.

“‘Our results demonstrate that natural selection can rapidly rewire regulatory networks,’” Shuker said. He put down the iPad.

“So it’s a perfect, beautiful example of rapid neo-Darwinian evolution,” he declared.

You have a dazzling new interpretation of the data? First thing you have to do is have a thorough grounding in what the established interpretation says. Second thing you ought to do is cull the loonies from your lineup so you can have a serious discussion. The third thing you should do is bring in people who can explain what the core ideas are, rather than just people with a self-aggrandizing axe to grind. People like Douglas Futuyma.

“I think I’m expected to represent the Jurassic view of evolution,” said Douglas Futuyma when he got up to the podium. Futuyma is a soft-spoken biologist at Stony Brook University in New York and the author of a leading textbook on evolution. In other words, he was the target of many complaints during the meeting that textbooks paid little heed to things like epigenetics and plasticity. In effect, Futuyma had been invited to tell his colleagues why those concepts were ignored.

“We must recognize that the core principles of the Modern Synthesis are strong and well-supported,” Futuyma declared. Not only that, he added, but the kinds of biology being discussed at the Royal Society weren’t actually all that new. The architects of the Modern Synthesis were already talking about them over 50 years ago. And there’s been a lot of research guided by the Modern Synthesis to make sense of them.

Take plasticity. The genetic variations in an animal or a plant govern the range of forms into which organism can develop. Mutations can alter that range. And mathematical models of natural selection show how it can favor some kinds of plasticity over others.

If the Extended Evolutionary Synthesis was so superfluous, then why was it gaining enough attention to warrant a meeting at the Royal Society? Futuyma suggested that its appeal was emotional rather than scientific. It made life an active force rather than the passive vehicle of mutations.

“I think what we find emotionally or aesthetically more appealing is not the basis for science,” Futuyma said.

I would add, though, that those people who argue that epigenetics implies that you can take active control of your genetic inheritance are full-on wackaloons. If that’s the vanguard of this new revolution in evolutionary theory, it’s doomed. If that’s your belief, you are in Mercola territory, and completely wrong.



from ScienceBlogs http://ift.tt/2gD8PQu

There was a conference sponsored by the Royal Society last month, titled New trends in evolutionary biology: biological, philosophical and social science perspectives. There have been a number of news stories about this event, some good, some bad. Here’s one: can you tell what’s wrong with it?

For example, speaking at the Royal Society was Melinda Zeder, who talked about the way in which modern synthesis fails to provide a reason for mankind’s turning to agriculture 10,00 years ago and its ensuing evolutionary impact. Growing crops may have taken years, so there could not have been a short-term evolutionary benefit to it. As Zeder told Quanta, “You don’t get the immediate gratification of grabbing some food and putting it in your mouth.” It’s also been theorized that a climate shift caused agriculture to bloom, but there’s no evidence of such a shift.

If you’re not seeing it yet, focus on this statement: Growing crops may have taken years, so there could not have been a short-term evolutionary benefit to it.

Think about it. Imagine…when I was born, I did not immediately inseminate a nearby female, instead waiting 24 years, and even if I had been capable, it would have taken her almost a year to produce offspring for me. Because it lacks immediate gratification, there can not be any short term evolutionary benefit to reproduction.

That’s embarrassingly idiotic. Evolution is something that happens to populations, not individuals, and short-term evolutionary advantages are those that produce a benefit for the next generation. A nomadic tribe sowing seeds at their camp in the spring before following the herds for the summer, so that when they return in the fall they find a crop of edibles that provide a consistent food source sounds exactly like the kind of short-term investment that would produce an evolutionary advantage.

But this whole article sounds this way, like it was written by a clueless reporter discussing a meeting of ambitious ignoramuses who don’t understand what they’re criticizing. Look at the title: How About a New Theory of Evolution with Less Natural Selection? Say what? You do know that evolutionary theory already includes multiple modes of evolutionary change beyond selection, and it has had them quantified and described since the 1930s, right? Every competent evolutionary biologist since the 1970s has embraced the mathematics of Kimura and Ohta and knows that evolution is not solely driven by selection, and at the same time, they have not shouted “Revolution!” at the inclusion of new, better, mathematical descriptions of the evolutionary process.

Likewise, many of the revolutionaries at this meeting talked about epigenetics as if it were some shocking new thing that could not possibly be accommodated in a neo-Darwinian framework. I just want to reply “Waddington, in the 1940s”, but I feel like it would be received in this crowd like saying “Darmok and Jalad at Tanagra”. They just don’t have the referents to understand it.

This reporter even mentions one of my primary objections to the invalid over-emphasis on epigenetics in evolution.

Scientists used to believe that when a offspring is born, it starts with a clean epigenomic slate. This turns out not to always be the case, at least in plants and fungi, and maybe in invertebrates. Some epigenetic tags survive, and thus “epigenetic inheritance” may play a role in the organism’s evolution.

First “used to believe”? When? This is simply sloppy history. Waddington’s epigenetic influences were largely abstract and hypothetical; they wouldn’t become more concrete until details about such phenomena as DNA and gene regulation and methylation were discovered. It’s clear that there are ongoing epigenetic changes during development, so obviously there can’t be an epigenetic state for the organism. The gamete is a specialized cell type, so it has to have its own special epigenetic marks; we see this in imprinting. Of course the epigenetic state of the oocyte is largely reset not to a “clean” state, whatever that means, but to a totipotent state, which is something altogether different. That some gene states that have physiological or morphological effects in the adult persist for multiple generations is neither surprising nor requiring major renovations of evolutionary theory.

I also have to point out that Jacob and Monod’s Lac operon work showed that E. coli passes on an epigenetic state after cell division. This is not a wild and crazy revelation that necessitates radical changes in the theory.

They also talk a lot about plasticity. Plasticity is important, no denying that, but plasticity has also not been ignored: I just want to chant another phrase, “Clausen, Keck, Hiesey, 1930s.” This is not a neglected topic.

I found this article infuriating because here we have a group of people declaring that we need to greatly modify the neo-Darwinian Synthesis but they constantly demonstrate that they don’t understand it. You can’t propose changes to an idea if you haven’t done your homework and shown some detailed knowledge of what you think needs revision. They haven’t done their background research.

Another problem I have with this kind of meeting is that they’re always infested with crackpots. This one had Denis Noble, and disgraceful dingleberry who believes that mutations are non-random and that acquired characteristics can be inherited and that evolutionary change is entirely saltational. He’s nuts. At least Carl Zimmer captured some of the pushback against Noble. I’ve got to admit it’s kind of hilarious to read about David Shuker shooting down Noble’s distortion of a paper.

“This strategy is to produce rapid evolutionary genome change in response to the unfavorable environment,” Noble declared to the audience. “It’s a self-maintaining system that enables a particular characteristic to occur independent of the DNA.”

That didn’t sound right to Shuker, and he was determined to challenge Noble after the applause died down.

“Could you comment at all on the mechanism underlying that discovery?” Shuker asked.

Noble stammered in reply. “The mechanism in general terms, I can, yes…” he said, and then started talking about networks and regulation and a desperate search for a solution to a crisis. “You’d have to go back to the original paper,” he then said.

While Noble was struggling to respond, Shuker went back to the paper on an iPad. And now he read the abstract in a booming voice.

“‘Our results demonstrate that natural selection can rapidly rewire regulatory networks,’” Shuker said. He put down the iPad.

“So it’s a perfect, beautiful example of rapid neo-Darwinian evolution,” he declared.

You have a dazzling new interpretation of the data? First thing you have to do is have a thorough grounding in what the established interpretation says. Second thing you ought to do is cull the loonies from your lineup so you can have a serious discussion. The third thing you should do is bring in people who can explain what the core ideas are, rather than just people with a self-aggrandizing axe to grind. People like Douglas Futuyma.

“I think I’m expected to represent the Jurassic view of evolution,” said Douglas Futuyma when he got up to the podium. Futuyma is a soft-spoken biologist at Stony Brook University in New York and the author of a leading textbook on evolution. In other words, he was the target of many complaints during the meeting that textbooks paid little heed to things like epigenetics and plasticity. In effect, Futuyma had been invited to tell his colleagues why those concepts were ignored.

“We must recognize that the core principles of the Modern Synthesis are strong and well-supported,” Futuyma declared. Not only that, he added, but the kinds of biology being discussed at the Royal Society weren’t actually all that new. The architects of the Modern Synthesis were already talking about them over 50 years ago. And there’s been a lot of research guided by the Modern Synthesis to make sense of them.

Take plasticity. The genetic variations in an animal or a plant govern the range of forms into which organism can develop. Mutations can alter that range. And mathematical models of natural selection show how it can favor some kinds of plasticity over others.

If the Extended Evolutionary Synthesis was so superfluous, then why was it gaining enough attention to warrant a meeting at the Royal Society? Futuyma suggested that its appeal was emotional rather than scientific. It made life an active force rather than the passive vehicle of mutations.

“I think what we find emotionally or aesthetically more appealing is not the basis for science,” Futuyma said.

I would add, though, that those people who argue that epigenetics implies that you can take active control of your genetic inheritance are full-on wackaloons. If that’s the vanguard of this new revolution in evolutionary theory, it’s doomed. If that’s your belief, you are in Mercola territory, and completely wrong.



from ScienceBlogs http://ift.tt/2gD8PQu

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