In his book The Structure of Scientific Revolution, Thomas Kuhn draws a parallel between Darwinian evolution and the evolution of scientific ideas. With respect to organic evolution, Kuhn states that "natural selection, operating in the given environment ... was responsible for the gradual but steady emergence of more elaborate, further articulated, and vastly more specialized organisms," and that the highly specialized organs of the human body are the product "of a process that moved steadily from primitive beginnings but toward no goal." Kuhn then draws a parallel between his description of organic evolution and the evolution of scientific ideas, describing science as the "net result of a sequence of ... revolutionary selections ... [into] the wonderfully adapted set of instruments we [now] call modern scientific knowledge," having developed "without benefit of a set goal."
The problem with Kuhn's description is that science does have a set goal: to approximate nature as best possible. It's not that we expect some particular (say, intelligently designed) information or structure to emerge, however, the definite goal of science is to systematize our understanding of reality as maximally as human consciousness permits. Scientific projects are undertaken with the express goal of refining and extending our understanding of nature, and as we pursue science our understanding of nature is guaranteed to develop, regardless of the fact that we may know not what the results will be.
Returning to Kuhn's parallel: biological adaptations directly impact an organism's capacity for survival, but even though some scientific ideas may prove "fitter" and thus "survive" better, science at large is not necessary for our basic survival. Biological developments evolved through a series of responses that were necessitated in some way by the environment. Science however is different. Science is a refined and self-correcting formalization of what we do reflexively when interacting with our environment. Man existed long before science did, and scientific pursuits are intellectual pursuits that are not provoked by the environment in the same way that biological responses are. There is an intelligence gap here: biological evolution is not intelligently designed, but science is.
The reason Kuhn employs the evolution analogy is to push the argument that epistemic realism is not possible. He believes knowledge is socially constructed, and that objective knowledge is inaccessible to us, and that the best science can do is to systematize only a specific social group's understanding of reality. Certainly, both Darwinian evolution and the evolution of scientific ideas enable the biological organism and the curious scientist to better navigate their environment, but the intelligence gap makes this a rather tenuous analogy. Kuhn himself notes "[t]he analogy that relates the evolution of organisms to the evolution of scientific ideas can easily be pushed too far," but it seems the analogy can not be pushed in this direction at all.