Tuesday, 29 November 2016

The evolution of observers and observations

Here's a draft of an essay I have written on the topic of observer and observation evolution.

Introduction

One of the places where mainstream physics has come closest to embracing Darwinism involves the role of observers. Physicists identified the role selection of observers plays, and identified it as the cause of goodness of fit between man and his environment - in the form of life-friendly physical laws and a stable planetary home.

History

Historically, the evolution of observers was first studied by a physicist called Brandon Carter in the 1970s. One of the ideas he came up was was that physical constants having values that made the universe habitable was not due to chance or an intelligent designer. It was no accident that we observed a universe with life-friendly physical laws, since it could not be otherwise: any observers in universes with physical laws that were not life friendly would rapidly perish. This idea was christened "the anthropic principle" and it was contrasted with the Copernican principle - which states that we are not in a special place in the universe. According to the anthropic principle we are in a very unusual place in the universe - one suitable for the evolution of humans over billions of years.

The result of the need for life-friendly physical laws is an adaptive fit between the universe and living systems inside it. The physicists didn't describe what they had discovered as an "adaptive" fit. Instead they said that the universe was 'fine tuned' for life. Most of the physicists involved didn't seem to link these ideas to evolutionary theory. Instead they seemed to consider it to be an entirely new area of science which they had discovered, one that could explain the appearance of design without invoking a designer. They did, however use the terminology of 'selection' to describe their findings - mirroring the terminology used in evolutionary theory. Retrospectively, it seems obvious that they were just applying Darwin's discovery to human observers.

Observation selection

A subsequent development was the discovery that a similar idea could be applied to observations, as well as to observers. Observations may be filtered in a number of ways - both before and after arriving at the senses. For example, publication bias filters information before it reaches an observer. An observer's expectations and preconceptions might then go on to filter information further before it reaches consciousness.

Observation of the observable

From one perspective, observation selection is one type of selection in the nervous system among many. Filters also control whether information is stored, when it is retrieved, and when it is forgotten. Still more filters are applied to ideas, action plans and motor outputs. However, if you look at the situation another way, observations seem to be fundamental - since all knowledge gains are made through observation. Observations are the basis of everything an organism knows. Everything else consists of inferences derived from observations. This gives observations a primary status. For example, if a fruit fly in an scientists's experiment dies, that's a case of natural selection. However the scientist doesn't learn about it until an observation is made. We can say that survival of the fittest is a special case of observation of the observable. This results in a reformulation of evolutionary theory puts observers at the heart of the theory. This broadly mirrors the changes in physics that happened at the turn of the last century, when it was discovered that observers played a surprisingly central role in physics.

Observation reproduction

Selection is only part of Darwinism. That many observers reproduce is perhaps too obvious to mention. However, observation reproduction merits a few comments. Behavioral reproduction is ubiquitous in human cultural transmission. It is widely agreed that humans often copy the behavior of other humans via behavioral imitation. However, behavior is only one side of behavioral imitation. To be copied, behaviors have to also be observed. Observations reproduce during this process just as behaviors do. To give an example of an observation that catalyzes its own reproduction consider the observation of yourself, snorting cocaine. Such an observation is often followed by more similar observations. This is a simple case of observation reproduction.

Beyond survival and reproduction

Observation selection illustrates how Darwinian dynamics can involve more than survival and reproduction. Observation selection also filters out things that are hidden from the observer. This allows evolutionary theory to be applied to cases where the observation of entities is based on their visibility - rather than because they and their ancestors survived and reproduce. Survival and reproduction are important determinants of what we observe, but they are not the only factors involved.

Multiverse

The idea that the visible universe is the product of selection effects suggests that the visible universe is part of a multiverse. It which case it would be helpful to know the size of the multiverse - and which parameters are free to vary in it. Alas we can only observe our small corner of the multiverse. This leads to a difficult inductive inference problem with very little data to go on. The concept of a "reference class" is sometimes used to denote the set of objects being selected from. When dealing with other possible worlds it isn't always clear what the set of worlds being selected from consists of - since we only see one world.

Brandon Carter's Ultra-Darwinism

One of the physicists who did recognize links to Darwinism was the originator the idea in the first place: Brandon Carter. He wrote in 1992 that: "anthropic selection should be considered as an adjunct to ordinary natural selection". He proposed that the union of anthropic selection and natural selection be called 'Ultra Darwinism'. That's pretty much the same thing that I am saying - except that Brandon used a different name. However, I would emphasize that the topic is mostly just applying basic Darwinian principles to observers and observations. There are a few other topics involved too - for example, the maximum entropy principle is used to handle ignorance. However, this is mostly ordinary Darwinism applied to observers and observations.

Terminology

The term "anthropic" turns out to be rather unfortunate. The "anthro-" prefix means: "man", but the basic idea can easily be generalized to cover animals, plants and machines. The human-based version of the idea seems anthropocentric to the point of being unscientific.

References

Thursday, 24 November 2016

Douglas Futuyma: no evolution revolution

Evolutionary revolutionaries face opposition from conservatives, who apparently like their evolutionary theory the way they were taught it in school. A case in point is Douglas Futuyma, well known as the author of a popular evolutionary biology textbook.

In the essay Can Modern Evolutionary Theory Explain Macroevolution? (see the "sample pages" link at the bottom of the page for the free PDF), Futuyma explains his perspective on various proposed changes to evolutionary theory - including changes proposed by students of cultural evolution. Thanks are due to Jerry Coyne for drawing attention to this paper.

The abstract starts:

Ever since the Evolutionary Synthesis of the 1930s and 1940s, some biologists have expressed doubt that the Synthetic Theory, based principally on mutation, genetic variation, and natural selection, adequately accounts for macroevolution, or evolution above the species level.

...and concludes:

I conclude that although several proposed extensions and seemingly unorthodox ideas have some merit, the observations they purport to explain can mostly be interpreted within the framework of the Synthetic Theory.
I think the essay goes after the wrong targets. The biggest change in our understanding of evolution since the 1930s has been the massive expansion of the domain of evolutionary theory - to include the Darwinian evolution of cultural variation, learned knowledge development systems and inorganic systems. Futuyma's treatment of this consists of a section entitled "Nongenetic Inheritance" - which mentions cultural inheritance, saying "Cultural characteristics such as language and wealth are nongenetically inherited". However he spends the rest of the section discussing a inheritance via meiosis and mitosis. That's it. The biggest revolution in evolutionary theory swept under the rug in one brief paragraph.

IMO, the second biggest change in evolutionary theory, since the 1930s is the revolution represented by symbiology. This conclusively added merging and joining operations to the basic evolutionary toolkit - which had previously consisted of splitting and selection. Surely any discussion of updating the modern synthesis ought to include some coverage of this change to the basic fundamentals of evolutionary theory. Futuyma gives this revolution one sentence. He writes: "possibly newly established endosymbioses will likewise have large but beneficial effects".

Since Futuyma offers so little coverage of what I consider to be the real revolutions in evolutionary theory since the 1930s, what does he talk about? S. J. Gould is mentioned 45 times in the essay. Alas, my rather dim view of S. J. Gould extends to those who take him seriously. I'm mostly OK with bashing Gould's proposed revolutions, but here they are distracting from the real action - and that's not OK.

The essay closes with the comment:

Of course, the Evolutionary Synthesis will be extended, molded, and modified. But there will not be a Kuhnian “paradigm shift.”
My take on the "paradigm shift" business is a bit different. Evolutionary theory caused a pretty dramatic shift in biology in the 1800s. It causes similarly dramatic shifts in other fields it enters. Evolutionary economics is a major shift for economics, evolutionary epistemology is a major shift for epistemology - and so on. What Futuyma is apparently talking about is a paradigm shift within evolutionary theory. Most of the claims for memetics as a paradigm shift aren't talking about that. For example, Richard Brodie, in Virus of the Mind (1996), says:

Viruses of the mind, and the whole science of memetics, represent a major paradigm shift in the science of the mind.

In Thought Contagion, Aaron Lynch (1998) wrote:

Memetics represents just such a paradigm shift. In a nutshell, it takes the much explored question of how people acquire ideas, and turns it on its head - the new approach asks how ideas acquire people.

These folks are talking about memetics as a paradigm shift within psychology.

Are memetics and universal Darwinism a paradigm shift within evolutionary theory? This raises the issue of what qualifies. I have described symbiology and the expansion of evolutionary theory's domain as being 'revolutions'. However, they clearly build on the existing theory. A "Kuhnian paradigm shift" doesn't seem to be a particularly well-defined scientific concept, so it is not always easy to see whether something qualifies or not. Ultimately it doesn't matter. What's more important is to digest and assimilate the revolutions. At this stage, I'm not convinced that Futuyma has done very much of that.

Does Futuyma have any understanding of cultural evolution? If there was evidence that he knew what he was talking about, I might give his opinion some more weight. It's hard to coherently argue against the significance of a scientific revolution when you don't even understand it.

Friday, 18 November 2016

Political memes

Obama won his last election with social media. Now Trump has won with social media. Political memes are officially a big thing. Throughout the election cycle, Trump was the more-discussed candidate on social media. The discussions were not always positive - but they made sure that Trump would win any contest based on the availability heuristic. There were some Clinton memes, but they were nowhere near as diverse, interesting and spreadable as the Trump memes. Love or loathe Trump, one has to acknowledge that he and his team have some marketing skills.

The Trump campaign illustrated the marketing heuristic that there's no such thing as bad news. The important thing is to get in the news. In many cases, it doesn't matter too much if the news reflects badly on you - so long as everyone is talking about you and discussing you.

I'd like to illustrate this article with an internet meme. Early in the campaign the Gregory brothers made a memorable video illustrating the Trump marketing tactics titled Donald Trump Sings & Dances. The video showed how Trump grabbed the media spotlight using provocative behavior - essentially by trolling everyone. The chorus lyrics go: "I love Mexicans they're rapists" - a mashup of Trump's contradictory comments.

It was easy to dismiss Trump during the campaign because his policy positions were so ridiculous. Building a 2000 mile wall along the Mexican border with North America is the most obvious example. However, because his ideas were ridiculous, people discussed them, ridiculed them - and in the process, shared them. Trump went along with his memes for the ride, using memetic hitchhiking. It worked. Now America has four years of Donald Trump as president of the union.

Daniel Dennett is Bach

Daniel Dennett is coming out with his book on cultural evolution in 2017. Here's the Amazon page for the book. It says the book is coming out in February. The title is: From Bacteria to Bach and Back: The Evolution of Minds.

The blurb reads in part:

In From Bacteria to Bach and Back, [Dennett's] most comprehensive exploration of evolutionary thinking yet, he builds on ideas from computer science and biology to show how a comprehending mind could in fact have arisen from a mindless process of natural selection. Part philosophical whodunit, part bold scientific conjecture, this landmark work enlarges themes that have sustained Dennett’s legendary career at the forefront of philosophical thought. In his inimitable style―laced with wit and arresting thought experiments―Dennett explains that a crucial shift occurred when humans developed the ability to share memes, or ways of doing things not based in genetic instinct. Language, itself composed of memes, turbocharged this interplay. Competition among memes―a form of natural selection―produced thinking tools so well-designed that they gave us the power to design our own memes. The result, a mind that not only perceives and controls but can create and comprehend, was thus largely shaped by the process of cultural evolution.

Dennett has previously written on cultural evolution, in Darwin's Dangerous Idea, Consciousness Explained and Breaking The Spell. This looks set to be his first book largely devoted to the topic.

Monday, 14 November 2016

Cultural evolution vs cultural epidemiology

Jason Collins recently raised the issue of cultural evolution vs cultural epidemiology, thus:

Then there is the question of whether evolution is the right framework for all the forms of cultural transmission? Are models for the spread of disease a better fit? You will find plenty of discussions of this type of question across the cultural evolution literature, but little convergence.

I think it's fair to say this issue has been widely discussed - with some folks promoting "viruses of the mind" and "cultural virus theory" for example, and other folk criticizing them. However the issue is not very complicated and should not be that controversial. Here's a position summary that I think that most knowledgeable parties should be able to agree on:

Models of disease spread often need to be generalized before being applied to culture. One issue is the sign of the fitness correlation between symbiont and host. Diseases almost always have a negative fitness correlation with their hosts - i.e they reduce host fitness. By contrast, culture can have positive or negative effects on host fitness. The sign of the fitness impact matters, since negative fitness impacts on hosts are resisted and rejected, while positive fitness impacts on hosts are promoted and encouraged. Symbiology performs this generalization. However symbiology generally deals with close relationships. There's a larger field that deals with all kinds of relationships - known as biological interactions. Models of biological interactions are highly suitable for modeling cultural evolution.

Many models of epidemiology are explicitly evolutionary these days. It is widely recognized that parasites evolve in real time - including within host lifetimes. Less widely recognized, but still well-established science is the notion that host immune systems use evolution and natural selection to adapt to the parasites they face. Evolutionary epidemiology is clearly a thing. The main cases where non-evolutionary models of epidemiology are useful is when dealing with short time scales - or highly simplified models. For example, fleas might spread through an island community without either them or their hosts evolving very much. A similar cultural example of where a non-evolutionary epidemiological model might be appropriate is where Rubik cubes spread through a network of children in schools. Here, neither the cubes nor the children are doing much change or evolution. As a first approximation, models based on evolutionary theory can be ignored in favor of simple epidemiological models.

It is certainly true that in cultural evolution, epidemiological models are sometimes the most appropriate. The exact same thing is true in the organic realm. However evolutionary and epidemiological models are generally complementary and compatible - they are best used under different circumstances.

Wednesday, 2 November 2016

Teaching made us human

Like my Walking made us human idea, the idea on this page takes on the dominant "culture made us human" meme - pithily expressed by Richard Dawkins in 1976:

Most of what is unusual about man can be summed up in one word: 'culture'.
That idea is dominant - at least among most students of cultural evolution. Walking, talking, tool use, our big brains and even our opposable thumbs are largely the product of cultural evolution - plus some meme-gene coevolution.

However, cultural evolution is fairly ubiquitous among other animals. This had led to people to seek out other answers to the question of "what made us human?". Cumulative cultural evolution is one common answer. However, an issue with this answer is that chimpanzees have cumulative cultural evolution too. Teaching is much rarer in non-human animals. This helps to make it an interesting candidate for what makes humans special.

Here I want to examine another possible answer to this question - an idea based on what I have previously referred to as the "Teaching First" hypothesis. To recap, the "Teaching First" hypothesis turns the usual story about the evolution of cultural evolution on its head. It is usually thought that some change in social learning abilities was responsible for the modern explosion in cultural evolution. Maybe a slightly bigger brain, maybe slightly less aggression - something affecting social learning. The the "Teaching First" hypothesis represents a considerable shift away from this perspective - a shift from social learning to teaching.

In some respects, teaching is more a product of cultural evolution than social learning is. Teaching requires some age, experience and previous social learning. Because teaching is cultural, it is more subject to rapid change. Cultural evolution is an example of large organisms using small symbiotes to adapt quickly. The short reproduction cycles of memes (relative to their human hosts) is part of the reason why it is faster.

We know that in many cases, memes lead and genes follow. If meme-gene co-evolution can be characterized as genes holding memes on a leash, then the memes are often dragging the genes around. The the "Teaching First" hypothesis would be another example of this kind of dynamics.

Teaching could have helped create a positive feedback loop - where improved culture relating to teaching leads to more teaching-related improvements in the future. The corresponding loop for learning exists too - but more learning capacities (than teaching capacities) are coded in DNA genes - so progress there is harder and slower.

Academics have don't seem to have looked into the idea that the cultural evolution of teaching drove cultural evolution very much. One related idea is the cultural evolution of cultural evolvability. An example of this is Cecilia Heyes' video: Cultural Inheritance of Cultural Learning. The corresponding paper is Grist and mills: on the cultural origins of cultural learning. This is more about social learning - but it has the idea of positive feedback on cultural learning capacities via cultural evolution. It is some of the nearest literature I know about.

Sunday, 23 October 2016

Dawkins 2015 WSJ interview on memes

Dawkins interviewed by WSJ in 2015. It is four minutes long. Memes are the topic.

Wednesday, 19 October 2016

Metamorphosis: the symbiosis hypothesis

Symbiology is a core concept in cultural evolution. Cultural creatures act as though they are parasites, mutualists or commensals with their human hosts. This is fundamental to understanding the dynamics of their evolution. That's all about cultural evolution for this post - the rest is all about symbiology.

As part of my interest in symbiology I have recently explored the controversial work of Don Williamson on the origins of larvae. Williamson has promoted the idea of radical hybridization being involved in the origins of caterpillars into butterflies - and many other larval forms. For example here is his paper, Caterpillars evolved from onychophorans by hybridogenesis. Basically, Williamson claims that ancestors of modern butterflies may have had their eggs fertilized with sperm from velvet worms. Williamson's work has been widely ridiculed and castigated.

Like many students of symbiosis I am attracted to the possibility of biological metamorphosis arising as a result of fusion between widely separated forms. However, I think that there are more possible mechanisms than radical inter-species hybridization.

I have long thought that another possibility for the evolution of biological metamorphosis involves extended symbiosis. This idea shares the idea that larvae and adults started out as individuals members of separate species - but doesn't depend on the viability of radical hybrids. In an extended close symbiosis, parties can transfer genes gradually - via viruses or sperm-mediated gene transfer. They can also assimilate their partner's traits gradually through learning and ordinary natural selection. Radical hybrids are not needed in this kind of scenario - instead evolutionary assimilation can be gradual.

This symbiosis-based theory seems like a clear possibility to me. It holds that at one stage a wasp-like creature planted eggs in a caterpillar-like creature. These parties developed a close relationship and coevolved until one party assimilated the other. Their mutual descendants are caterpillars into butterflies. It is fairly well known that symbiosis promotes horizontal gene transfer. Mutualism, or at least mutual dependence, probably increases its likelihood.

The symbiosis hypothesis would be boosted by discoveries of wasps that have evolved mutualisms with their egg incubators. Wasps are commonly parasites and their incubators are destroyed my multiple wasps during wasp reproduction. However if a relationship develops in which one wasp hatches from one worm, the situation starts to look a bit more like the caterpillar into butterfly metamorphosis scenario. Such cases are in fact known - for example, see here for an example involving a single wasp egg per incubator. Exactly how parasitism might turn into mutualism in this case is not obvious - but there are plenty of other cases where parasites have evolved into benign partners and then into obligate mutualists.

Like Williamson's idea this theory would be boosted by genetic evidence which supported gene transfer. However, since it is not obvious what the ancestral species were, such evidence may remian elusive. The theory doesn't depend on such evidence existing - maybe no gene transfer was involved and one partner assimilated the other one via learning and natural selection. That makes the theory harder to refute - which is not normally considered a virtue among scientists. However, I think we need an alternative to radical hybridization that preserves the idea of separate origins - which itself is strongly suggested by the phenomenon of metamorphosis, according to multiple lines of evidence.

References

Monday, 3 October 2016

The significance of symbiosis in evolutionary theory

Before the discovery of the importance of symbiosis, evolutionary theory worked with a few fundamental operations - prominently including splitting and mutation. The history of life was viewed as a branching tree with branches diverging, but not converging again, at least not once they had fully divided. Life had an associated family tree.

Symbiosis represented a significant revolution in evolutionary theory because it introduced a new operation into the fundamentals of evolutionary theory: merging or joining. If splitting looks like this:

-> ->

...then joining looks like the time-reversed operation - like this:

-> ->

Before the 1900s, merging and joining operations were not completely foreign to evolutionary theory. The fusion of male and female gametes was a find of merging operation, though one that was confined by species boundaries. It was also known that some creatures lived inside other ones - such as gut bacteria - and that parasites regularly forged new associations with their hosts. However such intimate relationships were not widely thought to involve permanent fusion between previously unrelated organisms. Instead they were mere ecological associations.

The pioneers of symbiosis were mostly Russian. Though they discovered symbiosis early in the 20th century, their theories were ignored in the west until the 1960s, when it was discovered that mitochondria contained their own DNA lineages. Over the next 30 years, evidence accumulated that unrelated organisms could fuse together permanently, generating new kinds of recombination operation distinct from sex. Gaining or losing symbionts could be profound and dramatic evolutionary events - sometimes triggering speciation. The phenomenon was not confined to bacteria, but affected organisms of all sizes. We now know that eucaryotic cells are unions of many free living ancestors, that viruses carry DNA between all kinds of different species, and that around 10% of the human genome shows signs of origins outside our own species. Horizontal gene transfer has turned the tree of life into a web. Multi-cellular organisms are now widely viewed as being menageries.

In modern times, the evolutionary significance of symbiotic unions is familiar to us, so it is sometimes hard to appreciate the scale of the revolution the idea represented, and the resistance that it faced at the time. Evolution was generally though of as being gradual - yet in symbiogenesis, entire genomes could join forces in an evolutionary instant. This idea violated established dogma and was widely rejected and ridiculed for over 50 years. An avalanche of facts and data eventually vindicated the idea. At the time, this was the the biggest revolution in evolutionary theory since Darwin - eclipsing the discovery of DNA, kin selection and Mendelian inheritance, in my humble opinion.

In cultural evolution, the story went rather differently. In 1975, Ted Cloak pioneered a symbiosis-based version of cultural evolution, in which human hosts cultivated cultural symbionts inside their brains. Richard Dawkins went on to popularize the idea in the 1976 book The Selfish Gene. These cultural "memes" were sometimes characterized as being "viruses of the mind". However, in academia, symbiosis was very slow to catch on. Many academics didn't seem to cotton on to the fundamental concept of a cultural organism - instead opting to model culture as an aspect of the host's phenotype. This was a bit like modeling smallpox without the concept of the smallpox virus - and instead talking about horizontal and oblique transmission of the smallpox rash phenotype. Many of the researchers in the field are still laboring under the resulting hangover. Symbiosis enthusiasts were one tribe of biologists and cultural evolution enthusiasts were another. The intersection included Ted Cloak, Richard Dawkins and Ben Cullen - but only a few others. What this meant in practice was that concepts such as parasitism, mutualism, domestication, parental care and arms races tended to get neglected by most students of cultural evolution.

The slow uptake of symbiology among cultural evolution researchers is an aspect of cultural evolution's scientific lag. Most anthropologists long ago demonized evolution and expelled it from their halls as a dastardly idea that they wanted nothing to do with. The important topic of cultural evolution subsequently suffered from lack of attention and funding - and progress has been slow as a result. It wasn't until the 1980s that symbiology gained acceptance among mainstream evolutionary biologists. There's clearly still a long way to go before most students of cultural evolution start applying the idea properly.

Friday, 30 September 2016

Joe Henrich: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter

The blurb reads:

The ability of human groups to socially interconnect and learn from one another has allowed us to create ingenious technologies, sophisticated languages, and complex institutions that have enabled successful expansion into myriad environments. Drawing insights from lost European explorers, clever chimpanzees, mobile hunter-gatherers, neuroscience, ancient bones, and the human genome, Joseph Henrich, author of The Secret of Our Success, will discuss how our collective intelligence has propelled our species’ evolution.

Some similar recent book talks:

Also, here are some recent videos relating to evolutionary psychology, most of which feature Joe Henrich:

The Leda Cosmides video is interesting because she responds to the cultural evolution enthusiasts. Leda specialized in culture and evolution, but almost completely missed memetics - adopting a position closely related to Wilson-style sociobiology. It now seems obvious that Darwinian cultural evolution is a very important concept - but Leda missed it. In the video she says the idea makes her "uncomfortable". Rightly so. That's cognitive dissonance for you. Leda Cosmides should say: "how extremely stupid not to have thought of that".