Memetic Lamarckism

From Memetics

Memetic Lamarckism

it is said memes and the ontology of memetics itself is to be lamarckian rather than darwinian, personally i think it is a degree of both, with more of it being lamarckian and a huge amount of variation depending on certain strategies of certain niches

adapted from[1]

see also[2]

In this sense, cultural inheritance is Lamarckian ( Maynard Smith & Szathmáry 1999 , 140).

According to the Lamarckian version of evolution, the characteristics acquired in the course of an organism's life can be passed on to that organism's offspring. Or, in other words, the variations in an organism's phenotype can be transmitted to its genotype and thus be inherited by the organism's offspring.

Genetic Lamarckism was refuted at the end of the 19th century by Augustus Weismann with his famous doctrine of the separation between germ and soma (better known as the Weismannian Barrier ). According to this theory, the separation between those lineages of cells destined to become germinal or reproductive cells and the lineages of cells destined to become somatic or body cells would take place at a very early stage in embryogeny. The implications of this find were crucial, for it meant that whatever events may happen to an individual organism, they will not affect its progeny, as there is no way for them to be transmitted to its germinal cells. (In this way, for instance, if a man loses one leg, such loss is not reflected in his genotype, and his children need not be born lame). Thus, Lamarckian inheritance - the inheritance of acquired traits - was rejected.

Diagram of the Weismannian Barrier: Two rows of 3 circles each. The top row circles are all labeled S, the bottom are all labeled G. Each G has a arrow pointing to the S above it. Each G has an arrow pointing to the G circle to the right, while the rightmost circle's arrow points to nothing. The Weismannian Barrier G = germ, or reproductive cells S = soma, or body cells (organism)

Weismann's distinction between soma and germ corresponds to that between phenotype and genotype. In this way, the Weismannian Barrier can be reformulated, stating that the genotype produces the phenotype, but changes in the phenotype bear no effect upon the genotype.

Given the identification that idealist memetics establishes between the (replicating) genotype and the meme qua concept, on the one hand, and between the phenotype and the meme qua object, on the other, the characterization of processes of cultural transmission as "Lamarckian" would thus seem to have a certain plausibility. Dawkins himself contemplates such a possibility in his Extended Phenotype:

The equivalent of Weismannianism is less rigid for memes than for genes; there may be "Lamarckian" causal arrows going from phenotype to replicator, as well as in the other sense ( Dawkins 1992 , 112).

That would result in a scheme similar to this:

Diagram of the Memetic Lamarckism: Two rows of 3 circles each. The top row of circles are labeled P1, P2, P3. The bottom row circles are labeled G1, G2, G3. Each numbered pair of circles have bidirectional arrows between the two. Arrows point from G1 to G2, G2 to G3, and to the right of G3. Memetic Lamarckism G x = genotypic meme or memotype P x = phenotypic meme or phemotype

>One of the most common objections to Lamarckism is that most of the changes effected on organisms by the environment are non-adaptive: they are usually the result of injury, disease, and aging. A genetic system which had a mechanism of "reverse translation," by which information about the adult phenotype might be incorporated to the genetic message passed on to the next generation, would lead to degeneracy, not to adaptation. But, as Maynard Smith points out, if there were some way of selecting for transmission only those phenotypic traits which would prove adaptive, not only would adaptive change endure, but it would also speed up. Indeed, that is precisely what cultural evolution is all about. As Szathmáry has expressed it,

whereas genes are weismannian replicators, with no flow of information back from the phenotype, memes are lamarckian ones, relying on reverse encoding from the phenotype, as if genetics canonically included something akin to reverse translation, or at least to some other means of inheriting acquired traits. The immediate consequence is higher variability and the potential for cultural evolution to be much faster than genetic evolution ( Szathmáry 2002 , 370).