Of the Wells' motive, Alan D. Gishlick wrote: It is clear from Wells's treatment of the "icons" and his grading scheme that his interest is not to improve the teaching of evolution, but rather to teach anti-evolutionism. Under Wells's scheme, teachers would be hostile to evolution as part of biology instruction. Wells and his allies hope that this would open the door to alternatives to evolution (such as "intelligent design") without actually having to support them with science...In conclusion, the scholarship of "Icons" is substandard and the conclusions of the book are unsupported. In fact, despite his touted scientific credentials, Wells doesn't produce a single piece of original research to support his position. Instead, Wells parasitizes on other scientists' legitimate work. Likewise Frederick Crews of "The New York Review of Books" wrote: "Wells mines the standard evolutionary textbooks for exaggerated claims and misleading examples, which he counts as marks against evolution itself. His goal, of course, is not to improve the next editions of those books but to get them replaced by ID counterparts."