I usually have a rule that it is best to read one’s own work only when it is unavoidable (because one often finds things that could have been done better, etc.). However, I have been working on finishing up my most recent paper for Evolution: Education and Outreach, and I have had to go back through a few of my previous articles in the process. In a few places, I noted a particularly decent line that I thought I would probably quote sometime if it had been written by someone else. It then occurred to me that one can, in blog format at least, quote oneself and not feel too vain about it. So, here are the ones I liked.

From Evolution as fact, theory, and path:

“That evolution is a theory in the proper scientific sense means that there is both a fact of evolution to be explained, and a well-supported mechanistic framework to account for it. To claim that evolution is “just a theory” is to reveal both a profound ignorance of modern biological knowledge and a deep misunderstanding of the basic nature of science.”

“Evolutionary biology has as its purview the entire history and diversity of life, encompassing an unbroken chain of ancestry and descent involving innumerable organisms and spanning billions of years. In light of the tremendous scope and complexity of its subject matter, it should come as no surprise that details regarding the path and mechanisms of evolution are often subject to heated debate. The fact of evolution, however, remains unsinged.”

From The evolution of complex organs:

“As a career, science would hold very little appeal if all it entailed were the confirmation of existing knowledge or the memorization of long lists of well established facts. Science thrives on what is not yet known: the more vexing a problem, the more inspiring it is to investigate.”

“…the evolution of complex organs does not involve re-design from scratch at each stage; whether by direct adaptation or shifts in function, the process builds upon and modifies what is already present. “

“By definition, natural selection is the non-random differential success of individuals on the basis of heritable variation and therefore the cumulative outcome of this process – adaptation – is the opposite of random chance.”

“Because organs are built by tinkering rather than design, their features are impacted by historical contingency and inevitably reflect holdovers of past states. The net result is that all complex organs represent a mixture of optimizations and imperfections, both of which are accounted for by their evolutionary history.”

“Following in the tradition of Paley (1802) from two centuries ago, it is sometimes asserted that if a natural explanation is unavailable to account for an observation, then the only alternative is to assume a supernatural one. Such an assumption misses the obvious third option, and the one that drives scientific inquiry: that there is a natural explanation that is not yet known.”

From Artificial selection and domestication: modern lessons from Darwin’s enduring analogy:

“No reliable observation has yet been made to refute the notion that livestock, pets, and crops evolved from wild predecessors. On the contrary, the details of when, where, and how this occurred are becoming increasingly clear. Where there is disagreement, it relates not to the fact of evolutionary descent but to specific points about the mechanisms, locations, or timing of change. All of these considerations apply in the study of evolution by natural selection as well.”

From Understanding natural selection: essential concepts and common misconceptions:

“The occurrence of any particular beneficial mutation may be very improbable, but natural selection is very effective at causing these individually unlikely improvements to accumulate. Natural selection is an improbability concentrator.”

“The process of adaptation by natural selection is not forward-looking, and it cannot produce features on the grounds that they might become beneficial sometime in the future. In fact, adaptations are always to the conditions experienced by generations in the past.”

“Intuitive interpretations of the world, though sufficient for navigating daily life, are usually fundamentally at odds with scientific principles. If common sense were more than superficially accurate, scientific explanations would be less counterintuitive, but they also would be largely unnecessary.”

“…it is abundantly clear that teaching and learning natural selection must include efforts to identify, confront, and supplant misconceptions. Most of these derive from deeply held conceptual biases that may have been present since childhood. Natural selection, like most complex scientific theories, runs counter to common experience and therefore competes – usually unsuccessfully – with intuitive ideas about inheritance, variation, function, intentionality, and probability. The tendency, both outside and within academic settings, to use inaccurate language to describe evolutionary phenomena probably serves to reinforce these problems.”

“Natural selection is a central component of modern evolutionary theory, which in turn is the unifying theme of all biology. Without a grasp of this process and its consequences, it is simply impossible to understand, even in basic terms, how and why life has become so marvelously diverse.”

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Some more (I will use this page as the main collection):

From Darwin’s two-for-one deal (Globe and Mail):

“There are two major reasons that scientists accept common descent as fact. The first is that it is supported by, and accounts for, a multitude of independent observations, including data from genetics, developmental biology, the fossil record, comparative anatomy, and the geographical distribution of species. The second is that not a single observation or inference made over the past 150 years has provided convincing evidence that modern species are not descended from common ancestors. The notion of common descent has even withstood the rise of entirely new scientific disciplines, including molecular genetics and, most recently, comparisons of entire genomes.”

“Evolution is not “just a theory,” any more than germs, atoms, or gravity are “just a theory”. The common ancestry shared by all life is the unifying principle of biology, making sense of an otherwise bewildering array of diversity and complexity. Our understanding of how this has occurred is, itself, constantly evolving.”