 Notice that Ariew’s proposal hinges on a particular view of Waddington’s metaphor and its cognitive status. Ariew takes this metaphor to provide a mechanistic explanation of developmental invariance. This is the purported benefit of Ariew’s canalization account over the invariance proposal. As he explains, “It is this sense of [environmental] canalization that accounts for the invariance effect that is central to Sober’s account of biological innateness. But better than a mere invariance account, the effect is grounded in a real developmental pathway” (Ariew 2007, 579). Linquist (2018) raises doubts about this claim. When we think carefully about Waddington’s landscape metaphor, he argues, it is difficult to see how it could be regarded as an actual causal mechanism or even an idealized a model of a mechanism. Instead, most molecular biologists view canalization as a phenomenon to be explained rather than as a mechanism that does any explaining. As Greg Gibson and Günter Wagner note, “There are likely to be many molecular mechanisms involved [in canalization], including genetic redundancy, feedback regulation, and cooperative biochemical interactions” (2000, 373–74). They go on to state that “[t]hese are more phenomenological descriptions, however, than quantitative explanations of buffering.” If these more specific proposals are regarded by developmental biologists as “merely phenomenological descriptions” and thus fall short of explaining canalization, where does this leave Waddington’s broader and less specific landscape metaphor? Linquist’s (2018) contention is that any explanatory insight provided by Waddington’s metaphor is merely apparent. Much like the norm of reaction, this metaphor merely describes the phenomenon of environmental invariance without explaining it.