Meme FUD in the "Dual inheritance theory" article on Wikipedia

The "Dual inheritance theory" article on Wikipedia contains quite a lot of FUD in its section about memetics. I've looked at this article previously - but here I will here responses to all its points:

Memetics, which comes from the meme idea described in Dawkins's The Selfish Gene, is similar to DIT in that it treats culture as an evolutionary process that is distinct from genetic transmission. However, there are some philosophical differences between memetics and DIT.

True so far.

One difference is that memetics' focus is on the selection potential of discrete replicators (memes), where DIT allows for transmission of both non-replicators and non-discrete cultural variants.

Both Dual inheritance theory and memetics focus on small pieces of cultural information. The "cultural variants" of Boyd and Richerson are the same thing as the "memes and memeplexes" of memetics. They are not "more discrete", nor do they differ in their degree of replicatability - they are different terms for the same idea. If there is a difference it is that memetics draws a distinction between "memes" and "memeplexes", while the "cultural variants" terminology which Boyd and Richerson prefer bundles these two concepts together. That difference is surely not a big deal.

DIT does not assume that replicators are necessary for cumulative adaptive evolution.

That is not a difference. High-fidelity information transfer is necessary for cumulative adaptive evolution. High fidelity transmission in the underlying channel is not (because of error correction). This is just basic information theory. For more details see the essay here.

DIT also more strongly emphasizes the role of genetic inheritance in shaping the capacity for cultural evolution.

Quite a bit has been written about "memetic immunity". The 1992 book "Coevolution: Genes, Culture, and Human Diversity" is saturated with both memes and all kinds of interactions with genetic inheritance. It seems obvious that culture is supported by adaptations - for example speech and breath control. This is widely recognised. So: differences in this area seem to be of rather minor significance.

But perhaps the biggest difference is a difference in academic lineage. Memetics as a label is more influential in popular culture than in academia.

Those bits are both true.

Critics of memetics argue that it is lacking in empirical support or is conceptually ill-founded, and question whether there is hope for the memetic research program succeeding.

Right - but one doesn't judge a research program by what its critics say about it!

Proponents point out that many cultural traits are discrete, and that many existing models of cultural inheritance assume discrete cultural units, and hence involve memes.

Actually most proponents I am aware of think that this material about memetics not including "non-discrete culture" is a bunch of nonsense. Memetics is no different from dual inheritance theory in this regard. This proponent does not defend memetics in that way at all.

The reference provided in support of this sentence is the entire book "Sense and Nonsense" (2002). I've read that book - and it doesn't defend memetics in that way either. Not that Laland and Brown are big sympathisers towards memetics in the first place.

Culture exists in analog forms. Such forms have a heritable basis, and so are composed of memes. This really is not a problem.

If in doubt, see the definitions of the term "meme" in dictionaries. Nowhere does it say that memes are discrete entities which can't represent analog forms or blending inheritance.
Update 2016-08-16. A more detailed reference has been added to the Wikipedia article giving a page number. The pages in question still provides no support for the thesis.

Environmental inheritance

Environmental inheritance refers to inheritance via the environment. It includes cultural evolution - but also other types of heritable environmental influences.

If I give my son a big suitcase full of gold bars when I die, few would claim this is a case of cultural inheritance. Yet it is pretty clearly a form of inheritance.

The Big Three

Environmental inheritance is the third of the "Big Three" inheritance channels available to natural systems:

• Organic inheritance;
  
• Cultural inheritance;
  
• Environmental inheritance;

Diagram

Representing these forms of inheritance as a diagram, it looks something like this:

Here you will see that cultural inheritance is represented as a subset of environmental inheritace. This is because all culture must currently necessarily be represented "in the environment" at some point during its transmission down the generations.

Significance

Non-cultural environmental inheritance is pretty important. It typically includes your place on the planet, the ecosystem you are born into, and a bunch of non-cultural resources that result from modification of the environment by your ancestors.

Xemes and Xemetics

If memes are defined as only transmitting culturally-inherited information, it would be nice to have another term for environmental inheritance. I propose Xemes (based on eXternal transmission). Xemetics could be the science of Xemes. Xemes is pronounced rather like "Zemes" - NOT "eX-emes".

Implications for Dual Inheritance Theory

Non-cultural environmental inheritance is one of the big things that is wrong with Dual Inheritance Theory.

IMHO, non-cultural environmental inheritance is big enough and important enough to make Dual Inheritance Theory seem as though it has a very silly name.

Videos

John Odling-Smee - Construction Dynamics Seminar Series - Niche Construction and Niche Inheritance.

Niche construction intro video.

References

• Ecological inheritance;
  
• Dual Inheritance Theory;
  
• Niche construction;
• nicheconstruction.com.

Dual Inheritance Theory

For an introduction to "Dual Inheritance Theory" (DIT), see the page on Wikipedia titled Dual inheritance theory.

This is basically Memetics without the "M" word from my perspective - and since one of the primary points of memetics is to provide some nice terminology for those who study cultural evolution, I think that sucks.

The page contains a list of differences between DIT and memetics.

It claims memetics focuses on replicators, while DIT allows looser forms of cultural transmission. A complete theory of cultural evolution should obviously include those systems with low-fidelity transmission. They are evidently capable of cumulative adaptations, if used in conjunction with error correction.

However, IMO, memetics doesn't insist on high fidelity transmission, any more than genetics does. Rather what is needed for cumulative adaptations is Shannon mutual information between ancestors and distant descendants. High mutation rates don't invalidate evolutionary theory. They are just high mutation rates. That is true for both genetic and cultural evolution - for both genetics and memetics.

The idea that memetics is concerned with high fidelity replicators probably comes from Richard Dawkins - since he says things rather like that.

The idea that genetics is concerned with high fidelity replicators probably comes from the idea that genetics is the study of DNA - which is usually a high-fidelity replicator in biology. However, I take a broader perspective. Biology is the study of life - but that doesn't just include organisms made of DNA. It includes all living things, everywhere - including aliens, and virtual life, and future synthetic life. Genetics is the study of inheritance in living things. That need not necessarily involve high fidelity transmission of data - though it had better involve high fidelity transmission of information, or cumulative adaptations (and life) are impossible.

So, the idea that memetics is tied to the notion of high fidelity replicators comes from a fundamental misconception people have about the nature of biology and genetics.

Genetics shouldn't necessarily imply high fidelity data replication - and so neither should memetics, which is just genetics applied to culture.

DIT is mostly a rechristening of memetics, minus its widespread terminology, and supposed connotations of high-fidelity transmission.

Update: I revisit this Wikipedia article here.