Saturday, 31 January 2015

Cultural transmission explains human aquatic features

Elaine Morgan popularized the idea that humans are "aquatic apes" - who spent part of their evolutionary history in water. The aquatic ape hypothesis proved controversial.

I think it is pretty obvious that humans are more water-friendly than most other apes. However, the most likely explanation for this is that humans invaded water environments much as they invaded every other habitat on the planet - by using cultural transmission to adapt to these environments while also shielding themselves from their more negative aspects.

That humans are cultural apes is pretty uncontroversial. Cultural transmission explains practically every difference between humans and chimpanzees. It seems likely that it also explains those differences associated with adaptedness to aquatic environments.

Cultural transmission of traits that help with survival in the water are well known, and have been observed in primitive tribes. Cultural transmission of swimming, diving and breath holding are all old phenomena. Similarly many of the negative aspects of oceanic environments can be protected against using cultural transmission. Drowning can be learned about; sea predators can be defended against, hypothermia can be avoided or treated - and so on.

Some aspects of these behaviours fossilize. For example, we can be pretty sure that humans have been diving for pearls for thousands of years - because we can see the resulting pearls. We also know some things about the rafting feats of early humans - through looking at the geographic distribution of human genes in islands. We know roughly who rafted where and when. Modern humans don't normally get onto ocean-faring rafts unless they can swim pretty well.

I think that cultural evolution is a sufficient explanation for human traits associated with water-friendliness. For example, there is no pressing need to invoke any environmental flooding to explain why humans are as water friendly as they are. Also, the idea that watery environments led to bipedalism (through the need to keep the nose out of the water) is weakened by the cultural explanation. Cultural transmission explains most of the observed facts without invoking this particular speculation. Instead cultural transmission led to bipedalism too.


Wednesday, 28 January 2015

A persistent group selectionist hangover

Cultural group selection has led to much confusion. One of the associated confusions is the idea that group selection is more prevalent in the cultural realm than in the organic realm.

This idea appeared prominently in "Not By Genes Alone". Here's what Boyd and Richerson wrote back then:

The real scientific question is what kinds of population structure can produce enough variation between groups so that selection at that level can have an important effect? The answer to this question is fairly straightforward. Selection between large groups of unrelated individuals is not usually an important force in organic evolution. Even very small amounts of migration are sufficient to reduce the genetic variation between groups to such a low level that group selection is not important. However, as we will explain below, the same conclusion does not hold for cultural variation.

It is correct that selection between large groups of unrelated individuals is not usually important. However it is wrong to say that this conclusion does not apply to cultural variation. There the relevant 'individuals' are bibles, dollars and iPhones. These cultural individuals are often related with r~=1. Without relatedness kin selection doesn't work - and neither does group selection.

The idea that group selection works better in the cultural domain has been knocked around by various group selection advocates since then - apparently in an attempt to make cultural group selection seem more plausible. The idea is also beloved of those who like to exaggerate the differences between the cultural and organic realms. The latest endorser of the idea is Razib Khan - in his recent article Language (Culture) and Genes Evolve Differently. Razib gives the following rationale:

Not only is there a great deal of horizontal transmission, but cultural processes are subject to a greater “mutation” rate, and selection can be much more efficacious. The latter is why group level selection is more mathematically plausible for culture than genes; competing demes can be much more distinct in culture than genes because minimal gene flow can equilibrate biological differences, while biased transmission of culture can result in insulation of different groups from homogenization (e.g., inheriting your cultural traits from your father, rather than your mother, who may have been kidnapped from an enemy tribe).

To be plain, there's no supporting evidence for the idea that cultural group selection is any more prevalent than organic group selection. The whole idea is one of the fantasies introduced by group selection advocates.

The now widely-recognized broad equivalence of kin selection and group selection should have obliterated this fallacy - since kin selection is clearly broadly applicable to both realms - and it is patently false that kin selection doesn't apply to the organic realm - as Boyd and Richerson originally claimed for group selection.

In fact, both the organic and cultural realms exhibit superorganisms, eusociality - and all manner of milder forms of kin selection.

Why does the idea that group selection applies more to culture than to the rest of biology continue to lead a zombie existence - long after it has lost any sembalance of a credible empirical or theoretical basis? It isn't clear. Cultural lag is probably involved. Anyway, this article is here to drive another nail into the coffin of this dud idea. R.I.P.


Sunday, 25 January 2015

Memes and the "machines only do what you tell them to" fallacy

I've finished reading and reviewing Probably Approximately Correct: Nature's Algorithms for Learning and Prospering in a Complex World by Leslie Valiant.

It didn't make it into my review, but one comment in the book seemed especially naive to me. Leslie says:

The most singular capability of living organisms on Earth must be that of survival. Anything that survives for billions of years, and many millions of generations, must be good at it. Fortunately, there is no reason for us to endow robots with this same capability. Even if their intelligence becomes superior to ours in a wide range of measures, there is no reason to believe that they would deploy this in the interests of their survival over ours unless we go out of our way to make them do just that. We have limited fear of domesticated animals. We do not necessarily have to fear intelligent robots either. They will not resist being switched off, unless we provide them with the same heritage of extreme survival training that our own ancestors had been subject to on Earth.
For most readers familiar with the topic of machine intelligence it is probably obvious why this is wrong. Survival is a universal instrumental value. You typically don't need to deliberately program it in.

I think a basic smattering of memetics could have avoided this error. Memes are evolved to be good at surviving, just as genes are. They too have extended evolutionary histories during which they are subject to natural selection. This is likely to be true of intelligent machines, just as it is true of many cultural entities today. Today's cultural entities may not have survived for billions of years - but they often have a good number of generations behind them - and many of them plainly exhibit adaptations for survival.

Machine intelligence enthusiasts tread a difficult line. On the one hand they don't want to exaggerate the dangers of their products - since Terminator-savvy consumers may agree with them. On the other hand, they should not exaggerate the safety of their product category - or they will appear over-confident about the potential negative side effects of their products. Consumers don't by a hedge trimmers from manufacturers who thinks that hedge trimmers are totally safe and don't need special safety features. I think Leslie is erring too much on the size of being blazeƩ.

One of the reasons I got into memetics in the first place because I believed that a proper science of cultural evolution was too important to be left to cultural anthropologists - who had demonstrably failed to get to grips with the topic for over a hundred years. I think that machine intelligence enthusiasts should take steps to understand this topic. Part of the reason is to avoid making this sort of mistake. We now have a great science of cultural evolution - which is very useful for understanding issues associated with the coming era of intelligent machines. However people have to study and learn about the subject before it is of very much use to them.

Thursday, 22 January 2015

Darwin Does Physics is now widely available

Darwin Does Physics - by John Campbell - is now widely available.

The blurb reads:

A largely unnoticed scientific revolution has occurred over the past forty-five years. The Darwinian paradigm has been successfully applied to numerous fields outside of biology: including the Social Sciences, the Behavioural Sciences and most recently to the Physical Sciences and even to Physics itself. This revolution promises an unprecedented conceptual unification of the many branches of science. Darwin Does Physics argues that the extension of the Darwinian paradigm has proceeded in parallel with a more widely recognized scientific revolution concerning the fundamental importance of information throughout science. Information is seen to enter nature in the form of ‘inferential systems’ which accumulate knowledge required for existence. Darwinian processes are identified as the physical implementation of inferential systems. The theoretical paradigms of physics have struggled over the past hundred years to accommodate the massive increase in scope of the known universe which Physics’ must explain. The Newtonian paradigm, which includes most of its modern theoretical structures such as string theory, has been found wanting. In an attempt to circumvent these problems some physicists are now developing theories in the Darwinian paradigm to explain the most basic processes of physics. These theories are explained and suggestions made for their development. If Darwinian theories are proved successful in explaining even the fundamental physical mysteries science will have achieved a wondrous unification of its many diverse branches.
John Campbell previously wrote the generally excellent book Universal Darwinism. Darwin Does Physics looks set to be a small step for John Campbell but a large leap for most of the rest of the evolution comminity. Let's hope that some people actually read it.

John has posted an excerpt on his blog: Bayesian and Frequentist probability.

Sunday, 18 January 2015

The minimum constraint on mutation

One criticism of Universal Darwinism is that the core principles it is based on - namely heredity, mutation and selection - are too general, are capable of explaining anything and therefore explain nothing.

This criticism was made, for example, in:

They say that the principles of:

variation, selection and inheritance [...] are but an empty hull that lacks own explanatory substance.
There's a sense in which this is true. The problem is with the "mutation" operation. Unconstrained mutation predicts everything and is useless.

Neo-Darwinism avoids this issue - by claiming that mutations are "undirected". However, this is not really an acceptable approach in cultural evolution - where it is widely agreed that mutations are not remotely random - and that modeling them as being "undirected" is a coarse and limited approach.

I generally attribute the correct resolution of this issue to Donald Campbell. He basically said that variation was generated on the basis of existing knowledge. He used the unfortunate term "blind" to describe this - which has led to endless misunderstandings of his idea by confused critics.

Gary Cziko's terminology from the title of his book, without miracles is another approach to the problem. The term "without miracles" expresses the idea that mutations should be explicable naturalistically. While naturalistic explanations are good, scientists normally take it for granted that their explanations should be plausible within a naturalistic framework. The idea that mutations do not involve "miracles" isn't really all that much of a constraint - and the more scientific theories constrain expectations the more valuable they are.

This article tries to answer the question of what the minimum constraints on mutation are that avoid the accusation that the resulting theory is vacuous. The answer is pretty simple: all that is necessary is that mutations should be limited. If an evolutionary sequence requires mutations that exceed the mutation limit, they violate the predictions made by the theory.

This constraint is even weaker than the requirement that mutations should be naturalistically plausible. On one hand the idea of mutations being limited (in some specified way) is vague and not very useful. However it does show how easy it is to avoid the accusation that Universal Darwinism is empty and vacuous. Just put a limit (any limit) on the type of mutations permitted by the theory, and you have a falsifiable theory.

Wednesday, 7 January 2015

Blindness - or modeling simplification?

One systematic problem I have noticed with many with social scientists is that they don't always seem to understand the virtue of simplified models. Any model simplification is latched on to as an inaccurate weakness - and becomes the target of criticism.

I've gone into this issue before, in the article: Parsimony in the social sciences - with Jonathan Haight as my foil.

The phenomenon is part of the trigger-happy nature of many social scientists. Historically they have been better at criticism than theory construction. As a result, many social science domains became theoretical wastelands - with researchers systematically failing to grasp even basic theories - such as Darwinism. I've previously covered that phenomenon in the article: Can cultural evolution explain the lack of theory in the social sciences?.

If the virtues of simplified models are not obvious, perhaps read Boyd and Richerson's Simple Models of Complex Phenomena. If you think that article is stating the obvious, that's great. However, many social scientists seem to badly need to read this type of content.

This time, around it is Pascal Boyer who's rubbing me up the wrong way - by being critical of modelling simplification. He objects to lumping the various forms of copying in cultural evolution together - calling it "cognition blindness". Apparently all the different forms of social learning have their own unique cognitive quirks - and a failure to build detailed models of them makes you guilty of "cognition blindness". Here's Pascal:

Cognition-blindness is reponsible for many of the horrors we hear and read in the domain of cultural evolution - e.g. that culture is transmitted because people internalize norms, because they engage in ‘learning’, because they can imitate, because they copy prestigious individuals, or they copy what works, and so forth. If people tried to formulate these common ideas in computationally tractable terms, they would see how problematic they are. But there’s the rub – folk-psychological notions like ‘copying’ or ‘learning’ seem to describe self-evident, straightforward processes, so that many people think using such terms actually describe mechanisms.

This seems to be a pretty ridiculous comment to me. When aspects of cognition involved in copying are ignored, that's generally a modelling simplification. In much the same way, biological modellers frequently assume that the population is infinite, that mutations are random, or that mate choice is random. It isn't that they think that these things are literally true, it's that it is often useful to build models which ignore these elements - in order to better concentrate on other ones.

Of course, there's such a thing as over-simplification. Sometimes simplifications really do eliminate important features or result in inaccurate models or predictions. However, step one in understanding when a simplification is an over-simplification is to appreciate the virtues of simplified models - so that you can perform a cost-benefit analysis. Labeling modeling simplifications as a form of "blindness" probably doesn't help researchers to perform a clear-headed analysis.

Sunday, 4 January 2015

Factory-produced organisms

Here's Philon on factory-produced organisms:

The biotechnical ability to design novel organisms may well replace the *reproduction* of organisms with their *origination*, at least, to a considerable extent

I too think that many future organisms will be produced in factories. Indeed today, many types of electronic equipment are already being manufactured in factories.

However, I would point out that factory-produced organisms are not exactly new. Termites are essentially produced in factories. A termite worker isn't made by another termite worker reproducing itself - it is created in an enormous termite manufacturing facility on a kind of assembly line.

It seems fairly clear that evolution is in the process of transitioning to more factory-produced organisms. The model where organisms create their descendants directly via splitting or eggs only makes sense in a limited number of contexts.

As well as more factories I believe we will also see more hospitals. Large organisms often need repair - there should be dedicated facilities for doing that.

Sex and gender will never get old

People seem to regularly declare that advanced creatures won't have sex or gender.

For example, Mark Ridley argued for genderless 'angels' in The Cooperative Gene / Mendel's Demon, writing:

Earthling life is gendered, but this will probably prove to be a freakish condition in life as a whole in the universe.
I'm not convinced. The alleged advantage seems to be wider mate choice. However, that seems like a minor advantage to me - the pool of prospective mates for humans is already enormous.

In favour of gender is the possibility of specializations associated with gamete size. A seed spreading lifestyle and an egg-nurturing lifestyle are different - and they often demand different morphologies. In the organic realm, males are often small and mobile - rather like their gametes.

In the modern world, the "seed spreaders" are marketing and advertising departments. The "egg nurturers" are things like manufacturing facilities. Sometimes these are combined into single, 'hermaphrodite' organizations - but there are also separate organizations devoted to cultural "seed spreading" and organizations devoted to cultural "egg nurturing". Dimorphism based on gamete size occurs in the cultural realm as well as the organic realm. It seems likely that this is a general feature of evolutionary processes.

Recently, Robin Hanson has argued against angel sex, writing:

Second, it seems to me that sexual reproduction is quite unlikely to last. Today when we design software, devices, novels, and even organizations, we are almost never tempted to mix together random parts from different prior designs. Very advanced aliens should similarly design themselves deliberately, without much coin-flipping.
I would classify this as a basic misunderstanding of what sexual reproduction is all about. No definition of sexual reproduction I am aware of says that the recombination involved must be "random" - or based on "coin-flipping". Rather, sexual reproduction involves combining the traits from parent organisms to produce offspring organisms. Once this understanding of sexual reproduction is accepted, it becomes very unlikely that it will ever die out.

Sex reproduction could die out in two main ways: extinction or perfection. Universal extinction is unlikely - and attaining a universal perfect form is also unlikely. In between these extremes sexual reproduction flourishes. A universal perfect form is an unlikely outcome of evolution because the possibilities involved are so vast. Advanced organisms will include enormous creatures that run stellar farms. The idea that these will reach perfection and lose interest in exchanging heritable information with one another before the universe winds down does not seem credible - because of the enormous size of the search spaces involved and the immense difficulty of searching the space of possible genomes even today - when genomes are miniscule.

Sex is nature's masterpiece. It might be fun to speculate about its demise - but - but it is probably not very realistic.

Saturday, 3 January 2015

Delegation for humans

I've already written a large article about the important topic of delegation in evolution. However, because that article focuses on delegation as a general phenomena in evolution, it doesn't spend much time discussing delegation of tasks between humans. This article covers delegation of tasks by humans.

I've made this article into a bullet-pointed list - to make it easier to scan:

  • Delegation is an important social skill. Most people never get very good at it. They are at the bottom of the "delegation tree": they have tasks delegated to them, and don't do much delegation themselves.

  • Delegation facilitates hierarchical organization. If you can't delegate tasks, you can only do the things you know how to do. Getting other people to do things for you increases the tasks you are able to perform. It does this by augmenting your skills with the skills of others.

  • Delegation led directly to large-scale civilization. Without delegation, there's no civilization. Our delegation abilities drove progress.

  • Delegation often involves programming other humans. One of the core delegation strategies involves dividing a task into many pieces, which can potentially be performed in parallel - and dividing the task up between multiple workers, and then integrating the results. This operation is widely known as divide and conquer. Google's 'Map-Reduce' algorithm is based on this idea - as are the Hadoop and Spark projects.

  • Humans are experts at delegation. While other animals delegate tasks, humans are masters of delegation. Their programmability allows a wide range of tasks to be efficiently delegated.

  • Delegation is not confined to humans. Other animals can delegate. Social insects demonstrate delegation of tasks from queens to workers. Mutual grooming is a type of task delegation. Non-human animal parents frequently delegate tasks to their offspring.

  • Delegation fossilizes. The builders of the Egyptian pyramids used delegation. The people on Easter Island used delegation. If a civilization has mastered delegation, the fossil record bears witness to that.

  • Agriculture facilitated delegation. Increased population densities resulted in more willing workers.

  • Money and trade were key technologies enabling delegation. Bartering also allows you to trade favors with others - but Money and trade helped people to do things for each other on a larger scale.

  • The evolution of language helped people to delegate. Delegation ability was probably improved substantially by Turing-complete spoken languages.

  • Delegation is a core management skill. When people talk about management, they are often talking about delegation. Managing almost any large or complex project involves delegating some of the tasks to other agents. "Management" is a more general term than "delegation".

  • Programming humans is harder than programming machines. Machines, generally speaking, do what you tell them to do. They can be literal minded and hard to communicate with, but they are generally willing slaves. Humans, on the other hand, have conflicting allegiances. They need motivating. Rather than working as a team, they often like to compete with their co-workers. They get bored, sick and tired. They are sometimes deceptive. They steal your trade secrets. They resign.

  • Management is harder to automate that computer programming is. It is harder to automate than most tasks are. It's a fairly safe bet for those seeking job security while migrating away from the tide of automation.