Wednesday, 10 September 2014

Tim Tyler: Memetic hitchhiking


Hi. I'm Tim Tyler - and this is a video about memetic hitchhiking and memetic linkage.

Genetic hitchhiking involves genes changing in frequency due to their proximity to other genes. Hitchhiking can involve either positive or negative selection - in other words, increases or decreases in gene frequencies. Genetic hitchhiking is based on genetic linkage - which is the tendency of nearby genes to be inherited together.

In cultural evolution, there are corresponding effects:

Memetic hitchhiking involves memes changing in frequency due to their proximity to other memes. It is based on memetic linkage - which is the tendency of nearby memes to be inherited together.

It's a commonplace observation that the proximity of two memes is correlated with the probability of them being inherited together. This is true across a large variety of meme types. Words are more likely to be copied together the closer they are together. Image components and video fragments behave in the same way. Generally, the closer two memes are, the greater their memetic linkage. The way in which linkage changes with distance can often be fairly easily quantified.

Memetic hitchhiking is an extremely important concept in marketing. Memetic hitchhiking is used by marketers because they frequently face the problem of how to memetically engineer content so that it spreads to a large number of users. Hitchhiking on an existing meme is a common solution to this problem. People attach product messages as payloads to viral videos, celebrities, beauty, news stories, humour - anything that people spread around. When the viral content is spread around the payload is delivered to an increasingly large audience at a low cost to the marketing department.

For marketers their payload acts as a parasite on the original content. As such there's a constant risk that the viral content will find a way to separate itself from the payload. Marketers have a range of techniques to avoid this happening. They can interleave the payload with the content. They can make the payload small, short or inconspicuous. They can transmit the payload subliminally. They can launch legal attacks on payload-free content.

Well-known popular experts at memetic hitchhiking include Weird Al Yankovic, The Gregory Brothers, and Ray William Johnson.

Memetic linkage is generally defined in terms of a distance metric. That metric need not necessarily be spatial distance - for example in the case of podcasts or videos, time is often the most appropriate metric to measure. Genetic linkage is always based on a spatial distance metric. However, it seems inappropriate to restrict memetic linkage to spatial distance metrics.

Genetic linkage causes functionally dependent genes to migrate towards each other. Each gene benefits from the proximity - due to the increased linkage reducing the chances of the genes being separated from one another. The result is that genes form functionally-linked complexes. In memetics, the same effect is seen: functionally dependent memes tend to migrate towards each other - which increases their memetic linkage and reduces the chances of the memes being separated from one another. The result is that functionally-linked memes form memeplexes.

Not all hitchhiking of memes on memes qualifies as being "memetic hitchhiking". In the organic realm, a snail can hitchhike a ride on a duck's foot. However, you wouldn't normally call that "genetic hitchhiking" - even though in a sense,snail genes are "hitchhiking" on duck genes. The term "phenotypic hitchhiking" seems more appropriate there. Similarly you wouldn't normally refer to a bumper sticker on a car as a case of "memetic hitchhiking". The germ line of the memes responsible for the car are in the car manufacturers headquarters, and the germ line of the memes responsible for the bumper sticker are in the sticker-making factory - which might be nowhere near each other. Again, the term "phenotypic hitchhiking" seems more appropriate in this case.



  1. Hello Tim. I have a question for you. Recently I have been studying the deeps of how biological organisms replicate themselves. I've found that DNA can't replicate himself without the help of all the cell's machinery. Basically, for the replication to occur, we're gonna need oligonucleotides, molecular harvesting mechanisms, some enzymes that convert DNA to RNA, the ribosome, energy harvesting mechanisms... Thus comes the question: DNA probably was not the first replicator to exist in this world, there should have existed one that was more simple or more complex. If this replicator existed, why we don't find him in nature? There are research about this? Remember that plasmids and viruses aren't full-replicators, so, what them? ??????

    1. Later creatures ate the earlier ones. They were so successful that the earlier creatures did not survive. We can see that this happened at least once - because of the evidence for the RNA world. However, RNA probably wasn't first either (RNA is prebiotically implausible) - so there were probably many such complete defeats.
      Early forms can't start up again: more advanced creatures now occupy their niches and already ate their lunch.

  2. Thanks for answering. I am finding some research about this. To be exact there are some information about a possible precursor of RNA, the TNA. Also, I think the concept of eating is posterior to the TNA's concept, and means something such as taking another organism's machinery subparts for building it's own structure. From this comes the autotroph self-replicators that can build their own parts using only energy, matter and their surrounding micro niche.