The Selfish Gene was dropped. The book contains no illustrations. The book has been translated into at least 23 languages including Arabic, Thai and Turkish. In 2006, a 30th-anniversary edition was published with the Trivers foreword and a new introduction by the author. It was accompanied by a "festschrift" entitled "" (2006). In March 2006, a special event entitled "The Selfish Gene": Thirty Years On was held at the London School of Economics. In March 2011, Audible Inc published an audiobook edition narrated by Richard Dawkins and Lalla Ward. In 2016, Oxford University Press published a 40th anniversary edition with a new epilogue,
The Selfish Gene to behave selflessly with each other. A lineage is expected to evolve to maximise its inclusive fitness—the number of copies of its genes passed on globally (rather than by a particular individual). As a result, populations will tend towards an evolutionarily stable strategy. The book also coins the term "meme" for a unit of human cultural evolution analogous to the gene, suggesting that such "selfish" replication may also model human culture, in a different sense. Memetics has become the subject of many studies since the publication of the book. In raising awareness of Hamilton's ideas, as well as making its