Your exposition of Dawkins' ideas is neat, and probably helpful to people in an introductory biology course. I'd like to help clarify some of your comments on t

Your exposition of Dawkins' ideas is neat, and probably helpful to people in an introductory biology course. I'd like to help clarify some of your comments on the genome. > Even your DNA is not really a unified whole, it's a bunch of genes that have glommed together in a cooperative effort to reproduce themselves, but it's not an organized or homogeneous effort. That's why you have freeloaders ("junk DNA") and defectors (cancer genes) who put their own interests above those of the group. "Cancer genes" don't exist in the sense that there aren't genes that specifically cause cancer. If there were then every individual with a full gene complement would get cancer. What you're referring to are certain alleles that can arise which change cellular processes so as to break cooperative patterning of cell behavior. If you're lecturing in evolution it might be nice to use a technically correct description to match the Dawkinsian semantic splicing you're resting on :) Call them "oncogenic alleles" instead. "Junk DNA" is a blind concept that conflates sequence complexity with function. The argument goes that these pieces of DNA are just copies of each other and serve no obvious purpose, thus they are junk that "freeloads" off their host. This ignores the fact that these elements exist in virtually all complex organisms, and have lineages that last tens or hundreds of millions of years, which is longer than the lifespan of most species. If they were only an energetic drag on their host they would be selected out over these time scales. Instead, they appear to serve important purposes in genomes. There is a huge amount of evidence that this "junk" is also an "organ" of the genome that provides essential function in an evolutionary sense. This perspective is old, more than 30 years, and the first reference to it I'm aware of is from a study in 1983 that showed that Escherichia coli with transposons evolved faster than those without: https://www.nature.com/articles/303633a0 https://www.nature.com/articles/303633a0