We last addressed how Cat Memes colonize the internet (and our hearts) through connecting with widely recognized cultural memes as well as our basic human emotions.
The work of Daniel W. VanArsdale on Chain Letter structure, emotional integration with human hosts and replicative ability is pivotal in developing memetic theory. Since Chain Letters contain more text than Cat Memes and fewer graphics, Chain Letters can be mined for quantitative data more easily. The linguistic structure can be analyzed, articulating the anatomy of the chain letter. VanArsdale's work is the first I've come across which analyses a printed text from the perspective of memetic theory.
He traces the lineage of chain letters from "letters from heaven" which circulated in Europe for several centuries. As the cultural environment changed, chain letters adapted, keying into different emotional and social drives. Focus shifted from religious motivations to money, good luck and social advocacy.
Letters threatening disaster if they weren't copied had a survival advantage as did letters including the affirmation "It works!". Even more compelling were ambiguous hints of future reward: "see what happens to you on the fourth day".
Most notably, VanArsdale investigates how chain letters set up distribution networks and key into basic human drives to gain human compliance. In the process of copying, innovation ("It works!") as well as mistakes in transcription (make 8 copies ~ make 88 copies) create mutations which sometimes provide survival advantage to a lineage of letters.
There is much work to be done in investigating chain letters. VanArsdale's work does not delve into e-mail chain letters nor examines how different forms of copying (handwritten, photocopy, free & fast email) impact the spread of chain letters.
Whether you're looking for a research topic or more concrete evidence of memes,
Chain Letter Evolution is a vital resource. Best of all, it's available online for free.