The Edge of Evolution
| Company type | Book |
|---|---|
| Industry | Publishing |
| Founded | 2007 |
| Founder | Michael Behe |
| Products | Book on intelligent design |
The Edge of Evolution: Exploring the Boundaries of Darwinism is a work on intelligent design authored by Discovery Institute associate Michael Behe, released by Free Press in 2007. Behe posits that although evolution can drive variations within species, its capacity to generate new forms is limited—this threshold, which he terms the "edge of evolution," exists between the levels of species and orders. He argues that established evolutionary processes fail to fully account for the diversity arising from the last universal ancestor, suggesting that an intelligent designer has significantly influenced life’s variety. This publication follows his earlier intelligent design book, Darwin's Black Box.
The book has found favor among creationist circles and individuals outside the biological sciences, yet it has been met with considerable skepticism and criticism from professional biology researchers concerning its approach, evidence, and interpretations.
Contents
Behe opens by clarifying three fundamental elements of the theory of evolution: common descent, natural selection, and random mutation. While he accepts both common descent and natural selection, he challenges the ability of random mutation to generate advantageous changes that lead to new biological structures. He defines "Darwinian evolution" as the process involving all three components and refers to those opposing intelligent design as "Darwinists."
He maintains that Darwinian evolution predominantly alters existing metabolic pathways—the 'molecular machinery'—rather than constructing novel ones, thereby limiting its contribution to biological complexity. Behe examines genetic differences between the genome of the malaria-causing plasmodium and that of humans, characterizing their interaction as a form of "trench warfare," which he contrasts with an evolutionary "arms race." This stands in opposition to the "creative process" necessary for developing intricate systems such as the bacterial flagellum or the immune system.
Using calculations based on mutation rates and population sizes, he delineates the "edge of evolution," concluding that intentional design plays a significant role by generating "non-random mutations" subsequently shaped by natural selection.
Behe supports his argument for design favoring intelligent life not only through biological complexity but also by citing chemical phenomena—like water’s exceptional properties conducive to life—and cosmological concepts including the anthropic principle.
He firmly endorses common descent across all forms of life, humans and chimpanzees included, describing this as "trivial" due to overwhelming supporting evidence. However, he contends that mutations responsible for transitions at higher taxonomic ranks are exceedingly unlikely without design intervention, defining this as the "edge of evolution." This reasoning hinges on the improbability of multiple simultaneous beneficial mutations and the limited microbial evolution observed in new proteins and binding sites.
Recognizing his position as a minority viewpoint within mainstream science, Behe refrains from elaborating on the specifics regarding the nature of the designer and distances himself from associations with the Young Earth creationism movement.
Reviews
Reviews from scientific experts, especially biologists, have been predominantly critical of Behe’s methodology and conclusions, largely dismissing his assertions. Conversely, some creationist groups and a minority of biologists have expressed more favorable opinions.
Negative reviews
Richard Dawkins, an evolutionary biologist from Oxford, contested Behe's assertion that evolution is primarily driven by nonrandom natural selection rather than random mutation. Dawkins highlighted selective breeding as evidence contradicting Behe's claim that random mutation alone cannot explain biological diversity. He also criticized Behe for neglecting engagement with scientific literature, suggesting that Behe's work would not withstand peer review and was tailored more for a general audience than for specialists.
Leading publications including The New Republic, Science, and Nature expressed similar reservations, noting that while Behe accepts much of evolutionary theory, he rejects the role of random mutation and substitutes it with the idea of guided mutations orchestrated by an unspecified designer.
Other critiques focus on Behe’s use of misleading quotations, his failure to present a detailed intelligent design framework despite over ten years since the release of Darwin's Black Box, contradictions between his concept of design and established natural laws, dependence on flawed models, and disregard for scientific findings that challenge his views. Specific points of dispute include Behe’s application of irrelevant calculations, his insistence on the necessity of simultaneous mutations despite evidence supporting cumulative mutations, and his omission of research on protein evolution.
Philosophy scholar Michael Ruse described the book as repetitive of earlier arguments without adequately addressing counterarguments. Dennis Venema, a Christian biology professor specializing in population genetics, observed that Behe’s treatment of this field revealed a lack of expertise, reinforcing the perception that Intelligent Design does not meet scientific standards.
Positive reviews
Cameron Wybrow, a historian of religion, reviewed Edge of Evolution in The Philadelphia Inquirer, remarking that the book "offers concrete data along with a clever argument." Additionally, minister Chuck Colson endorsed the book in The Christian Post, stating, "Even if you disagree with some aspects—as I do—you are not required to adopt the Darwinist stance that all opposing views must be dismissed."
Responses and scientific criticism
Behe has addressed his critics via his Amazon.com blog; however, some contend that his responses avoid engaging with the core scientific issues. Concerning critiques from Abbie Smith and Ian Musgrave, Behe admitted to an error related to HIV’s evolution of new protein binding sites but argued this mistake does not undermine his broader thesis.
Ian Musgrave, writing on The Panda's Thumb blog, disputed Behe’s central claim that protein–protein binding sites are highly improbable to evolve naturally. He referenced a Science publication showing that strong protein–protein interactions can result from a single mutation. Musgrave concluded that Behe exaggerates the difficulty involved in developing binding sites, overlooks instances of binding site duplication in vertebrates, and neglects their evolution in rapidly reproducing unicellular organisms. From Musgrave’s perspective, protein binding sites provide evidence supporting descent with modification and natural selection rather than indicating intervention by an unknown designer.